A publication of the Lunar Section of ALPO Edited by David Teske: [email protected] 2162 Enon Road, Louisville, Mississippi, USA Recent back issues: http://moon.scopesandscapes.com/tlo_back.html
June 2020 Online readers, click on images In This Issue for hyperlinks.
ALPO Conference Announcement 2 Lunar Calendar May 2020 3 An Invitation to Join ALPO 3 Observations Received 4 By the Number 6 Submission Through the ALPO Image Achieve 7 When Submitting Observations to the ALPO Lunar Section 8 Call For Observations Focus-On 8 Focus On Announcement 9 Euclides and Euclides Zeta, R. Hayes 10 The “X”, R. Hill 11 Von Braun, R. Hayes 12 Nicolas Again, R. Hill 13 Norman and Euclides C, Twin Craters, A. Anunziato 14 A Humid Place on the Moon, R. Hill 15 Landing in the Bay of Luna, D. Teske 16 Never Gets Old, R. Hill 19 A Possible Explanation for the Bright Spots in Mutus F. S. Babino and A. Anunziato 20 East of Nectar, R. Hill 23 Recent Topographic Studies 24 Lunar Geologic Change Detection Program T. Cook 78 Key to Images in this Issue 90
In this issue of The Lunar Observer, you will find a wide variety of lunar topics discussed, including topo- graphic forays by Rik Hill, Robert Hayes, Jr. and David Teske. Sergio Babino and Alberto Anunziato ex- plore lunar geologic change with an in-depth study of bright spots seen in crater Mutus F, as discussed in last month’s Lunar Geologic Change by Tony Cook. Tony Cook brings us another in-depth discussion about Lunar Geologic Change this month.
A few new things to be on the look-out for. On page 6, you will see “By the Numbers” about our observ- ers locations, observations and telescopes. Also, if you have not yet heard of the book Luna Cognita by Robert Garfinkle, check it out! Also, the USGS published a new lunar map, available at https:// www.usgs.gov/news/usgs-releases-first-ever-comprehensive-geologic-map-moon which is really nice!
The Lunar Observer/June 2020/ 1
ALPO Conference November 6-7, 2020
Interested parties are hereby invited to submit papers and research posters on the astronomy-related topics of their choice for presentation at the next ALPO conference to be held jointly with the Georgia Regional Astronomers Meeting (GRAM) when that group meets on November 6 and 7, 2020.
This will be the second time the ALPO has participated with the GRA group, the first time being the au- tumn of 2017.
Like last time, the was made after an online discussion and vote by the ALPO board of directors.
This year's conference will be at North Georgia College in Dalton, Georgia, approximately a one-and-a-half -hour drive north of downtown Atlanta. The ALPO portion of the conference will commence with the ALPO board meeting on Friday, November 6, to be followed by an informal gathering that evening with a lecture, social gathering with snacks and observing at the school’s on-campus observatory.
All papers will be presented the following day, Saturday, November 7, between 9 a.m. and 5 p.m.
Also as we did in 2017, there will be an ALPO dinner on Saturday evening where the Walter Haas Observ- ing Award and the Peggy Haas Service Award will be presented.
We have been allotted up to at least four (4) time slots for ALPO papers of no more than 15 minutes in length; the preferred method is 12 minutes for the paper presentation plus 3 minutes for follow-up ques- tions. The preferred format is Microsoft PowerPoint.
We have also been invited to participate with wall-mounted research posters which are also commonly done at academic and professional conferences everywhere.
Participants are encouraged to submit research papers, presentations, and experience reports concerning various aspects of Earth-based observational astronomy. Suggested topics for papers and presentations in- clude the following: • New or ongoing observing programs and studies, specifically, how those programs were designed, im- plemented and continue to function. • Results of personal or group studies of solar system or extra-solar system bodies. • New or ongoing activities involving astronomical instrumentation, construction or improvement. Challenges faced by Earth-based observers such as changing interest levels, deteriorating observing condi- tions brought about by possible global warming, etc. A hard-copy version of your paper should be made available for future web site publication.
More details about paper presentations and to whom they should be sent will be published in the Summer issue of the ALPO Journal for release in early June.
The Lunar Observer/June 2020/ 2
Lunar Calendar June 2020
Date Time UT Event June 2020 1 Lunar south limb most exposed -6.7o
3 0400 Moon at perigee, 364,366 km 5 1912 Full Moon, penumbral lunar eclipse 8 Moon greatest southern declination -24.0o 9 0200 Saturn 3o north of the Moon 9 Lunar east limb most exposed +5.9o 13 0 Mars 3o north of the Moon 13 0624 Last Quarter Moon 14 Lunar north limb most exposed +6.9o 15 0100 Moon at apogee, 404,595 km 19 0900 Venus 0.7o south of Moon, occultation East Canada to Mongolia 21 0641 New Moon, lunation 1206, annular solar eclipse 22 Moon greatest northern declination +24.1o 22 Lunar west limb most exposed -5.1o 28 0816 First Quarter Moon 8 Lunar south limb most exposed -6.8o 30 0200 Moon at perigee, 368,958 km
The Lunar Observer welcomes all lunar related images, drawings, articles, reviews of equipment and reviews of books. You do not have to be a member of ALPO to submit material, though membership is highly encouraged. Please see below for membership and near the end of The Lunar Observer for submission guidelines.
Comments and suggestions? Please send to David Teske, contact information page 1. Need a hard copy, please contact David Teske.
AN INVITATION TO JOIN THE A.L.P.O.
The Lunar Observer is a publication of the Association of Lunar and Planetary Observers that is available for access and participation by non- members free of charge, but there is more to the A.L.P.O. than a monthly lunar newsletter. If you are a nonmember you are invited to join our organization for its many other advantages. We have sections devoted to the observation of all types of bodies found in our solar system. Section coordinators collect and study members’ observations, correspond with observers, encourage beginners, and contribute reports to our Jour- nal at appropriate intervals. Our quarterly journal, The Journal of the Association of Lunar and Planetary Observers-The Strolling Astronomer, contains the results of the many observing programs which we sponsor including the drawings and images produced by indi- vidual amateurs. Additional information about the A.L.P.O. and its Journal is on-line at: http://www.alpo-astronomy.org. I invite you to spend a few minutes browsing the Section Pages to learn more about the fine work being done by your fellow amateur astronomers. To learn more about membership in the A.L.P.O. go to: http://www.alpo- astronomy.org/main/member.html which now also provides links so that you can enroll and pay your membership dues online.
The Lunar Observer/June 2020/ 3
Lunar Topographic Studies
Acting Coordinator – David Teske - [email protected]
Assistant Coordinator – William Dembowski - [email protected]
Assistant Coordinator – Jerry Hubbell – [email protected] Assistant Coordinator-Wayne Bailey– [email protected] Website: http://moon.scopesandscapes.com/
Observations Received June 2020
Many thanks for all these observations, images, and drawings.
Name Location and Organization Article/image Alberto Anunziato Paraná, Argentina Drawing and article Euclides C and Norman. Alberto Anunziato and Sergio Ba- Paraná, Argentina and Montevideo, Images and article A Possible Ex- bino Uruguay planation of Bright Spots in Mutus F. Aylen Borgatello AEA - Oro Verde, Entre Rios, Ar- Image of Hyginus N, Atlas and gentina Mons La Hire. Victor Cabrera-Peláez, Puebla, Mexico Image of size comparison of Moon at apogee and perigee. Francisco Alsina Cardinali Oro Verde, Argentina, SLA- Images of Langrenus, Atlas, Cassi- LIADA ni, Plato, Tycho (2), Messier (2), Taruntius and Ross D. Jairo Chavez Popayán, Colombia Image of 8% waxing crescent Moon, waxing gibbous Moon (3), Copernicus, Tycho, Mare Vaporum, Langrenus and Full Moon. Abel David Emiliano Gonzalez AEA - Oro Verde, Entre Rios, Ar- Images of Alphonsus (3), Coperni- Cian gentina cus, Aristarchus (2). Walter Ricardo Elias AEA- Oro Verde, Entre Rios, Ar- Images of Alphonsus, Copernicus gentina (3), Plato, Tycho, Kepler, Waning Gibbous Moon and Picard. Howard Eskildsen Ocala, Florida, USA Image of Herschel to Birt, Tycho, Copernicus, Mare Imbrium, the Serpentine Ridge, Lamont, the “western Chain” Marcelo Mojica Gundlach Cochabamba, Bolivia Images of Maginus, Vallis Alpes, Alphonsus, Bessel, Rima Hyginus, Cassini, Hyginus, Aristoteles, Jul- ius Caesar and Maurolycus. Robert Hayes Jr. Worth, Illinois, USA Article and drawing Euclides and Euclides Zeta and Von Braun.
The Lunar Observer/June 2020/ 4
Observations Received June 2020
Name Location and Organization Article/image
Rik Hill Tucson, Arizona, USA Article and images Nicolas Again, The “X”, A Humid Place On the Moon, Never Gets Old and East of Nectar, images of Clavius, Coper- nicus and Eratosthenes, Barrow, Cassini and the Caucasus, Apenni- nus, Alpes, Aristoteles to Hercules, Aristarchus to Mairan, Hainzel, Gassendi, Hadley, Mare Smythii, Lacus Excellentiae, Humboldt, Gemma Frisius, Ramsden, Marius, Mare Australe, Posidonius, Peek, Licetus and Thebit. Gabriel Jaimes Cochabamba, Bolivia Images of Tycho and Moon, Mars, Jupiter and Saturn. Luigi Morrone SNdR Luna UAI Agerola, Italy Images of Aristarchus, Bayer, Gas- sendi, Marius, Moretus, Schickard, Schiller and Sinus Iridum. Antonio Polo Image of the Apennines.
Re, Gabriel AEA - Oro Verde, Entre Rios, Ar- Images of Messier and Torricelli. gentina Guido Santacana San Juan, Puerto Rico, USA Images of the Alpine Valley, Apen- nines and Copernicus. Leandro Sid AEA - Oro Verde, Entre Rios, Images of Hyginus, Plato, Tycho, Argentina Copernicus, Alphonsus, Full Moon, Waning Gibbous Moon, Aristar- chus, Posidonius, Daniell, Messier, Theophilus and Menelaus. Fernando Surá San Nicolás de los Arroyos, Argen- Image of Theophilus. tina Michael Sweetman Tucson, Arizona, USA Images of Aristarchus and Gassen- di. David Teske Louisville, Mississippi, USA Image and article Landing in the Bay of Luna. Steve Thornton Images of Langrenus and Petavius.
Many thanks for all these observations, images, and drawings.
The Lunar Observer/June 2020/ 5
June 2020 The Lunar Observer By the Numbers
Telescope size 3.5 inches to 14 inches.
107 observations Please note, this does not include observations in Tony Cook’s Lunar Geologic Change article.
The Lunar Observer/June 2020/ 6
SUBMISSION THROUGH THE ALPO IMAGE ARCHIVE ALPO’s archives go back many years and preserve the many observations and reports made by am- ateur astronomers. ALPO’s galleries allow you to see on-line the thumbnail images of the submitted pictures/observations, as well as full size versions. It now is as simple as sending an email to include your images in the archives. Simply attach the image to an email addressed to [email protected] (lunar images). It is helpful if the filenames follow the naming convention : FEATURE-NAME_YYYY-MM-DD-HHMM.ext YYYY {0..9} Year MM {0..9} Month DD {0..9} Day HH {0..9} Hour (UT) MM {0..9} Minute (UT) .ext (file type extension) (NO spaces or special characters other than “_” or “-”. Spaces within a feature name should be replaced by “-”.) As an example the following file name would be a valid filename: Sinus-Iridum_2018-04-25-0916.jpg (Feature Sinus Iridum, Year 2018, Month April, Day 25, UT Time 09 hr16 min) Additional information requested for lunar images (next page) should, if possible, be included on the image. Alternatively, include the information in the submittal e-mail, and/or in the file name (in which case, the coordinator will superimpose it on the image before archiving). As always, additional commentary is always welcome and should be included in the submittal email, or attached as a separate file. If the filename does not conform to the standard, the staff member who uploads the image into the data base will make the changes prior to uploading the image(s). However, use of the recommended for- mat, reduces the effort to post the images significantly. Observers who submit digital versions of draw- ings should scan their images at a resolution of 72 dpi and save the file as a 8 1/2'“x 11” or A4 sized picture. Finally a word to the type and size of the submitted images. It is recommended that the image type of the file submitted be jpg. Other file types (such as png, bmp or tif) may be submitted, but may be converted to jpg at the discretion of the coordinator. Use the minimum file size that retains image detail (use jpg quality settings. Most single frame images are adequately represented at 200-300 kB). How- ever, images intended for photometric analysis should be submitted as tif or bmp files to avoid lossy compression. Images may still be submitted directly to the coordinators (as described on the next page). However, since all images submitted through the on-line gallery will be automatically forwarded to the coordinators, it has the advantage of not changing if coordinators change.
The Lunar Observer/June 2020/ 7
When submitting observations to the A.L.P.O. Lunar Section In addition to information specifically related to the observing program being addressed, the fol- lowing data should be included:
Name and location of observer Name of feature Date and time (UT) of observation (use month name or specify mm-dd-yyyy-hhmm or yyyy-mm-dd-hhmm) Filter (if used) Size and type of telescope used Magnification (for sketches) Medium employed (for photos and electronic images) Orientation of image: (North/South - East/West) Seeing: 0 to 10 (0-Worst 10-Best) Transparency: 1 to 6
Resolution appropriate to the image detail is preferred-it is not necessary to reduce the size of im- ages. Additional commentary accompanying images is always welcome. Items in bold are re- quired. Submissions lacking this basic information will be discarded.
Digitally submitted images should be sent to: David Teske – [email protected] Jerry Hubbell –[email protected] Wayne Bailey—[email protected]
Hard copy submissions should be mailed to David Teske at the address on page one.
CALL FOR OBSERVATIONS: FOCUS ON: Lunar 100 Focus on is a bi-monthly series of articles, which includes observations received for a specific fea- ture or class of features. The subject for the July 2020 edition will be the Lunar 100 numbers 11- 20. Observations at all phases and of all kinds (electronic or film based images, drawings, etc.) are welcomed and invited. Keep in mind that observations do not have to be recent ones, so search your files and/or add these features to your observing list and send your favorites to (both): Jerry Hubbell –[email protected] David Teske – [email protected]
Deadline for inclusion in the Lunar 100 numbers 11-20 article is June. 20, 2020
FUTURE FOCUS ON ARTICLES: In order to provide more lead time for contributors the following future targets have been selected: The next series of three will concentrate on subjects of the Selected Areas Program.
Subject TLO Issue Deadline Lunar 100 (numbers 11-20) July 2020 June 2020 Lunar 100 (numbers 21-30) August 2020 September 2020
The Lunar Observer/June 2020/ 8
Focus-On Announcement
We are pleased to announce the future Focus-On topics. These will be based on the Lunar 100 by Charles Wood. Every other month starting in May 2020 , the Focus-On articles will explore ten of the Lunar 100 targets. Targets 11-20 will be featured in the July 2020 The Lunar Observer. Submissions of articles, drawings, images, etc. due by June 20, 2020 to David Teske and Jerry Hubbell.
L Feature Name Significance Rükl Chart 11 Aristarchus Very bright crater with dark bands on its wall 18 12 Proclus Oblique impact rays 26 13 Gassendi Floor-fractured crater 52 14 Sinus Iridum Very large crater with missing rim 10 15 Straight Wall Best example of a lunar fault 54 16 Petavius Crater with a domed and fractured floor 59 17 Schröter’s Valley Giant sinuous rille 18 18 Mare Serenitatis dark edge Distinct mare areas with different compositions 24 19 Alpine Valley Lunar graben 54 20 Posidonius Floor-fractured crater 14
Explore the Lunar 100 on the link below: https://www.skyandtelescope.com/observing/celestial-objects-to-watch/the-lunar-100/
The Lunar 100: Features 1-10 May 2020 Issue – Due April 20, 2020 The Lunar 100: Features 11-20 July 2020 Issue – Due June 20, 2020 The Lunar 100: Features 21-30 September 2020 Issue – Due August 20, 2020 The Lunar 100: Features 31-40 November 2020 Issue – Due October 20, 2020 The Lunar 100: Features 41-50 January 2021 Issue – Due December 20, 2020 The Lunar 100: Features 51-60 March 2021 Issue – Due February 20, 2021 The Lunar 100: Features 61-70 May 2021 Issue – Due April 20, 2021 The Lunar 100: Features 71-80 July 2021 Issue – Due June 20, 2021 The Lunar 100: Features 81-90 September 2021 Issue – Due August 20, 2021 The Lunar 100: Features 91-100 November 2021 Issue – Due October 20, 2021 Jerry Hubbell –[email protected] David Teske – [email protected]
The Lunar Observer/June 2020/ 9
Euclides and Euclides Zeta Robert H. Hays, Jr.
Euclides & Euclides Zeta, Robert H. Hays, Jr., Worth, Illinois, USA. 07 December 2019 0345-0415 UT. 15 cm reflector, 170 x. Seeing 9-8/10, transparency 6.
I sketched this area on the evening of Dec. 6/7, 2019. This is in the southeast Oceanus Procellarum just west of Montes Riphaeus. Euclides is a crisp, deep mid-sized crater. It had much exterior as well as interior shadow at this time. It is the only conspicuous crater on the sketch. The other feature is Euclides zeta. This wide curved ridge is part of the ghost ring of Euclides P. Its south end is blunt, but a large peak protruded from its southwest side. The north end is anchored by another large peak, and comes to a point. A narrow parallel ridge begins at the southwest side peak and has swollen near Euclides zeta’s north tip. A large de- tached peak is nearby, and a smaller peak and ridge are west of this confused area. This ridge may be Eu- clides tau as shown on the Lunar Quadrant map. A chevron-shaped mountain is northeast of Euclides, and the pit Euclides J may be spotted there. A low mound and narrow ridge are north of the ‘chevron’, and three tiny peaks are just to its east. Three more tiny peaks are east of Euclides, and another peak and narrow ridge are farther east. The ‘chevron’ and nearby peaks are not shown on the Lunar Quadrant map. The area north of Euclides looks smooth, but a low, wide wrinkle is west of Euclides zeta. The elongated peak to its west is probably Euclides sigma. A tiny bright dot is on the east side of the wrinkle; its nature could not be deter- mined. A very low mound is northeast of the wrinkle, and has similar relief.
The Lunar Observer/June 2020/ 10
The “X” Rik Hill
Our best observing weather is when the days are hot, the evenings are warm and still. The colongitude was just right so this was a good night to get a look at the famous “X” on the Moon. Can you see it on the ter- minator? It lasts only for an hour or so. Here’s how you get there. The area below center of this image is dominated by the two circular pools of darkness that are Aliacensis (82 km) lower and Werner (71 km) above. A line between the centers of these two craters lead to the “X” formed by the walls of Blanchinus, La Caille, Purbach and several smaller features. Above Aliacensis and Werner is a nice flat floored crater Apianus (65 km) and further above that is a smaller crater Playfair (49 km). Near the top of the image is a pair of craters Azophi (49 km) and above it is the irregular Abenezra (43 km) with Geber (46 km) partially cut off by the edge of this image.
In the lower right of this image is the irregularly shaped Gemma Frisius (90 km) overlain by the smaller Goodacre (48 km) to the north. Lastly, is the roughly triangular and shadow filled crater Nonius (71 km) due south of our first crater landmark, Aliacensis. Enjoy this region but it will take a bit of work and pa- tience to catch the “X”!
Blanchinus “X”, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 30 April 2020 0224 UT, colongitude 355.3o. Dy- namax 6 tele- scope plus Good- win barlow, 665 nm filter, Skyris 445M camera. Seeing 8/10.
The Lunar Observer/June 2020/ 11
Von Braun Robert H. Hays, Jr.
Von Braun, Robert H. Hays, Jr., Worth, Illinois, USA. 11 December 2019 0554-0638 UT. 15 cm reflector, 170 x. Seeing 8- 9/10, transparency 6-4.
I observed this crater and vicinity on the night of December 10/11, 2019. This area is in far western Ocea- nus Procellarum, and the libration was relatively favorable. The Moon was only 23 hours before full. This crater is labeled Lavoisier D on the Lunar Quadrant map, and probably also on older maps. Von Braun is a shallow crater with either a ridge or rille on its floor. A gap in its east rim is partly filled by a peak. There may be one or two tiny breaks farther north. A wide curved ridge extends northward from von Braun, and Lavoisier M intrudes upon its south rim. Lavoisier E is immediately west of von Braun, and looks deeper, even allowing for its proximity to the terminator. Lavoisier B abuts the south rim of Lavoisier E. Its diffi- cult to tell if one overlaps the other, but the shadow of Lavoisier B was cast within Lavoisier E at this time. A modest peak is between Lavoisier M and B, and a curved shadow extends from this peak to near the La- voisier E and B junction. More elongated shadows are nearby, mostly north of Lavoisier E. This area was difficult to draw. One curved shadow nearly merged with the wide ridge north of von Braun. The detail east of von Braun was easier to draw. The largest intact feature there is the crisp crater Harding A. Two tiny peaks and a small pit are east of Harding A. Some ridges and peaks are farther south and look like part of an old ring. Three small craters and two strips of shadow are northeast of von Braun, and an isolated bright peak is farther east. The edge of Oceanus Procellarum is quite well-defined east and north of von Braun. It goes from Harding A, along the shadow strips, around the three small craters, then angles back to the ridge tip north of von Braun. The edge is less well defined farther south, but the floor of the old ring looks darker than terrain to the north.
The Lunar Observer/June 2020/ 12
Nicholas again Rik Hill
It’s hard to ignore some features on the Moon even if you have imaged them repeatedly. Such is the case with this old favorite, Copernicus (95 km) that the sharp-eyed among us can spot even without optical aid when the lighting is right.
This night I was using the Dynamax 6 with a Klee Barlow (2.8 x) for a focal ratio of f/28. What a magnifi- cent view! The hummocky terrain around this large crater is so well shown in this sunrise view. Wonder- ful shadows on the floor of the crater and the central peaks have not quite caught any light yet. To the up- per right are some of the many secondary craters from this massive impact with 2-5 km diameters. Below Copernicus is a figure-8 pair of craters. The larger (upper) one is Fauth (12 km) and below is Fauth A (9.6 km), two very identifiable craters that were made famous in the “Photo of the Century” taken by Lunar Or- biter 2 at 00:05 UT (then GMT) on 24 November 1966 from an altitude of 28.4 miles above the lunar sur- face, 150 miles due south of Copernicus, just about the bottom edge of the image. I’ve included a copy of that image as well for your enjoyment and comparison.
Not bad for a little 6” Dynamax!
Copernicus, Richard Hill, Tuc- son, Arizona, USA, Loudon Ob- servatory. 02 May 2020 0443 UT, colongitude 20.4o. Dy- namax 6 telescope with 2.8 x Klee barlow, 665 nm filter, Skyris 445M camera. Seeing 8- 9/10.
The Lunar Observer/June 2020/ 13
Norman and Euclides C, Twin Craters Alberto Anunziato
"This part of Oceanus Procellarum contains numerous mare ridges and small isolated hills, and is interest- ing for telescopic observation, specially under low illumination", says the well-known Atlas by Antonin Rükl in his Chart 41. So many accidents and many of them without a name…. The craters that appear so prominent near the terminator (31.4º colongitude) are Norman (north) and Euclid C (south). Both apparent- ly share the same diameter (10 kilometers) and both are isolated circular formations with the bowl shape and rounded flor typical of craters less than 15 kilometers in diameter, steep slopes and high walls. The most obvious difference between them is the shape and extent of the shadow they cast. Euclid C's shadow is rounded and emerge from a small bright area of the rim. Norman's shadow is longer and appears to corre- spond to a higher rim than Euclid C's west rim, and the bright zone is more widespread.
Norman and Euclid C are craters from the Eratosthenian period, generated by impacts on the eastern edge of Oceanus Procellarum. They seem to be subsequent to the formation of the dorsa that dominate the land- scape and have no identification name. Most of these dorsa are concentric to the edge of the Oceanus Pro- cellarum, although two radial ones are also observed, going from south to north. A somewhat dreamlike landscape, because we know that they are not very steep elevations (the highest is the one on the upper left edge, as we can deduce because it reflects more light and casts more shadow). Perhaps if I could walk through them, they could be a landscape similar to the orographic accident characteristic of my province, Entre Ríos: the “lomada”, a gentle elevation of a few meters, which costs little to climb but high enough to hide part of the landscape.
Norman and Euclides C, Alberto Anunziato, Paraná, Argentina. 02 May 2020 2240-2305 UT. Meade EX 105 tele- scope, 154 x.
The Lunar Observer/June 2020/ 14
A Humid Place on the Moon Rik Hill
The monster crater here is Gassendi (114 km diameter), a landmark for this colongitude on the north shore of Mare Humorum, the "Sea of Moisture". Gassendi was flooded during the same even that created the mare so we only see the tops of what once were magnificent central peaks. The faulted floor is always a enjoyable but I particularly like the detail in the walls of the crater as they catch these early rays of the ris- ing sun. Note the two notches in Gassendi's wall at about the 11 o'clock position. On LROC Quick Map they appear to be to impacts through the mountains giving the appearance at this lighting of being parallel rimae. The nice central peaks and rimae on the floor are provide a rich field for examination. There are 3 main rimae that diverge from a point to the east of the central peaks. Between two of them is a small crater, Gassendi N (3 km). The rima on the left side is only 1 km wide for much of its length.
Notice the Rimae Mersenius that run from the area west of Gassendi down south along the western shore of Humorum. The smallest craters identifiable on the mare are around 2 km diameter as measured with LROC Quick Map. The resolution limit for this aperture on the moon at perigee, which it nearly was this night, is about 1.4 km. (see: https://www.lpl.arizona.edu/~rhill/mincrater.html) so how was it possible to see that rima mentioned above? Linear features, especially in a high contrast situation like this where one wall of a canyon is in darkness and the other brightly lit by the Sun allow for such observations.
Gassendi, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 04 May 2020 0427 UT, colongitude 44.1o. Dynamax 6 telescope with 2 x barlow, 665 nm filter, Skyris 445M camera. Seeing 8-9/10.
The Lunar Observer/June 2020/ 15
Landing in the Bay of Luna David Teske
I finally had some good lunar viewing and imaging nights in early May 2020. The Moon was high in the sky and seeing was very good. On this particular evening, the northeastern shores of Mare Imbrium were just coming into the lunar morning twilight. The most prominent crater in the extreme northeast of Mare Imbrium is Cassini, the 56 km diameter crater, named after Giovanni-Domenico Cassini, the Italian born French astronomer who lived from 1625 to 1712. It was Cassini himself who first put this crater on a lunar map back in 1692. Rather than being young in age, the crater Cassini appears to be of Lower Imbrium age, which is 3.85 to 3.75 billion years old. Cassini stands out prominently as its outer crater wall appears rounded and smooth as its glacis has been partially covered by flows of Mare Imbrium lavas. The ejecta that lies in a ring around the outer crater wall appears remarkably smooth and wavy. This gives the impres- sion that the impact was in a semi fluid like mud. On Mars, these are called rampart craters and formed their shape and texture due to impact in subsurface ice. Certainly, that is not the case here! The floor of Cassini is slightly rounded and smooth. A chain of hills stretches from the inner eastern crater wall to near the 15 km diameter fresh crater, Cassini A. Between Cassini A and Cassin B (9 km) is the remains of Cas- sini’s central mountain peaks. Cassini has an interesting history as it was formed by an impact after the Imbrium Basin impact, but before mare lavas flooded the area. As the Mare Imbrium lavas inundated the area some long time later, lavas welled up and nearly flooded Cassini, nearly covering its central mountains and giving its glacis their smooth appearance.
To the southeast (lower-right) of Cassini lies the fresh young crater Theaetetus with a diameter of 25 km. Named after the Athenian friend of Plato’s, Theaetetus lived from 415 to 369 BC. The walls of Theaetetus rise 2.8 km above its smooth floor, but only 600 m above the lava plains of Mare Imbrium. There is a low central mound inside Theaetetus and a ridge of small hills can be seen about one crater diameter northwest (upper right) of the crater.
Out on the mare, Mons Piton is very bright to the right of Cassini. Named after a peak in the Teneriffe massif, Mons Piton has an area of about 200 km2 and a height of 2.3 km. It is perhaps more of a tall hill than a mountain. Looking closely, it is actually a double peak and one of the peaks there is small craterlet. Near sunrise (or sunset) Mons Piton and the mare ridges near it show dramatic shadows. Mons Piton is part of the remains on an inner ring of the Imbrium Basin.
The northern shore of Mare Imbrium is formed by Montes Alpes, a tremendous range of mountains named by the Polish astronomer Hevelius. They border the northeast area of Mare Imbrium over a distance of 280 km with an average height of 2.4 km. These lunar Alps are a portion of the wall of the Imbrium Basin. The side of the Alps facing Mare Imbrium is very mountainous, creating a front similar to the Apennines and behind that front are much smaller hills that get progressively smaller away from the front. The Alps are a surviving part of the middle one of three original rings around the Imbrium Basin. Mont Blanc is the highest peak in the Alpines chain with a height of 3.6 km an area of 200 km2, the same as Mons Piton. In this image, Mont Blanc is straight above Mons Piton, about halfway to the Alpine Valley.
The Montes Alpes are cut in two by Vallis Alpes. This valley is 170 km long with a maximum width if 11 km, lying radially to the Imbrium Basin. The Valley does not connect directly with Mare Imbrium, but ra- ther starts in an ill-defined bulbous area that Wilkins and Moore called an ‘amphitheater’ that is high in the Alps then runs downhill to end at the southern shore of Mare Frigoris. It consists of two parallel tectonic fracture zones similar to the Great Rift Valley of East Africa, between which the lunar surface subsided. The eastern wall is straighter than the western wall. There is no other counterpart to the Alpine Valley any- where on the Moon. If is actually a graben which is a terrain dropped between two roughly parallel faults. The Alpine Valley probably formed after the ejecta from the Imbrium impact was deposited with the center down-dropped so far that all the mountainous debris was buried under the lavas that welled up into the frac- tures. A sinuous rille can be seen running down the center of the Alpine Valley when the light is right (it can be seen in this image). This rille has a width of 0.55 km to 1 km at maximum with a depth of 80 to 240 km. It is probably a collapsed lava tube that ran down the rear slope of the Alpes.
The Lunar Observer/June 2020/ 16
On the right side of the image are the Montes Caucasus, a 520 km long continuation of the Apennines. These contain the highest peaks on the near side of the Moon, over 6 km tall. From these peaks, you could see over 140 km! On the right (east) edge of this image is the crater Calippus, a 32 km diameter fresh crater in the Caucasus highlands. Named after the Greek astronomer and pupil of Eudoxus c. 320 BC, the crater’s eastern wall runs in a straight line in a north to south direction. This might be a Triesnecker-like complex crater, but also may be an Imbrium basin secondary crater. Calippus, Theaetetus and Cassini make a nice almost equilateral triangle.
I now turn your attention southward towards the three large and beautiful craters t the bottom of the image. Farthest east (right) is the 39 km diameter crater Autolycus. Named after the Greek mathematician and as- tronomer c. 330 BC, Autolycus has a rough floor and a faint system of rays. This is a Triesnecker-like complex crater with slumped walls and a debris-strewn floor 3.4 km below its rim. It may be slightly older than Aristillus, its larger neighbor to its northwest. Named after the Greek astronomer c. 280 BC, Aristillus is a perfectly formed lunar crater 55 km in diameter with terraced inner walls and the central peaks promi- nent above its smooth floor. These massive central peaks tower 900 m above its floor. Outside the crater, Aristillus has a broad annular zone of melted ejecta piled up outside the crater’s wall. This ejecta covers the ghost crater just north of Aristillus that is 40 km in diameter and easy to see under these lighting condi- tions. Aristillus is the center of a weak but clearly identifiable ray system, which have largely faded. Both Aristillus and Autolycus are relatively young, having formed on top of the Imbrium lavas. The Apollo 15 mission dated these lavas at 3.25 billion years old, so these craters must be younger than that. Due to their faded ray system, they are likely Eratosthenian age, 3.15 to 1.1 billion years old.
At the bottom left of the image is Archimedes, the largest crater on Mare Imbrium with a diameter of 83 km and a depth of 1.6 km. Named after the Greek mathematician and physicist of Syracuse who lived from 287-212 BC (and yelled EUREKA! as he ran naked down the street upon realizing his body volume dis- placed an equal amount of bath water, but I digress), its floor is so smooth that Wilkins and Moore called it ‘mirror-like’. Archimedes is like Plato in that both are partially filled with lava. Archimedes floor is about the same level as Mare Imbrium. Since there are no breaches in the walls of Archimedes, it must have been flooded by lava that rose up through fractures beneath the crater. It is likely that Archimedes filled with lava 2.4 km deep, thus burying its central mountains. Though its floor is largely featureless, the brightest streak across it may be a ray from nearby Autolycus.
Northwest of Archimedes near the terminator is Montes Spitzbergen, a chain of mountains 60 km long. Individual peaks reach a height of 1.5 km above the lava surface. Immediately west of Spitzbergen is a long mare wrinkle ridge. It was named by M. Blagg as it was similarly shaped to the terrestrial Spitzber- gen.
Finally, an area between Archimedes and Aristillus are some wrinkle ridges. This is called Sinus Lunicus, the Bay of Luna. This is the site of the first touchdown of a space vehicle on the Moon, Luna 2 in 1959.
The Lunar Observer/June 2020/ 17
References
Chu, Alan, Wolfgang Paech, Mario Wigand & Storm Dunlop. 2012. The Cambridge Photographic Moon Atlas. Cambridge University Press, New York.
Kitt, Michael T. 1992. The Moon: An Observing Guide for Backyard Telescopes. Kalmbach Books, Waukesha.
Moore, John. 2014. Craters of the Near Side of the Moon.
Planck, Andrew. 2015. What’s Hot on the Moon Tonight? Moonscape Publishing LLC.
Rükl, Antonin: Atlas of the Moon, Kalmbach Books, 1990.
Shirao, Motomaro and Charles Wood. 2011. The Kaguya Lunar Atlas: The Moon in High Resolution. Springer, New York.
Wilkinson, John. 2011. The Moon in Close-Up. Spinger, Heidelberg.
Wlasuk, Peter. 2000. Observing the Moon, Springer
Wood, Charles. 2003. The Modern Moon: A Personal View. Sky Publishing Corp. Cam- bridge.
Wood, Charles & Mau- rice Collins. 2012. 21st Century Atlas of the Moon. Lunar Publish- ing, UIAI Inc., Wheel- ing.
Vallis Alpes, David Teske, Louisville, Mississippi, USA, 01 May 2020 at 0233 UT, colongitude 7.9o. 180 mm Takahashi Mewlon, IR blocking fil- ter, ZWOASI120mms, 500 frames, Firecapture, Registax, Photoshop. See- ing 8/10.
The Lunar Observer/June 2020/ 18
Never Gets Old Rik Hill
Another night with the Dynamax 6 I bought last winter (when I was too hurt to use it!), this time with sun- rise on one of the most beautiful craters on the Moon, Copernicus (95 km). Unlike my last image of this crater, this time we can see surrounding features. On the right side of the image is Eratosthenes (60 km) and between them hidden among the beautiful field of secondary craters from the Copernicus impact event is the ghost crater Stadius (71 km). Due north of Copernicus is Pytheas (20 km) with Montes Carpatus be- tween them. Just north of Copernicus in those mountains is the flat-floored crater Gay-Lussac (27 km). Note to the lower left of this crater is a nice rima, appropriately named Rima Gay-Lussac. On the southern edge of this image is the crater Reinhold (49 km). The area between Reinhold and Copernicus is Mare In- sularum bordered on the right (east) by the figure-8 pair of craters Fauth (12 km) north and Fauth A (9.6 km) south.
Copernicus, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 03 April 2020 0221 UT, colongitude 28.8o. Dynamax 6 telescope plus 1.5 x barlow, 610 nm filter, Skyris 445M camera. Seeing 8/10 with thin clouds.
The Lunar Observer/June 2020/ 19
Lunar Geologic Change
A Possible Explanation for the Bright Points in Mutus F Sergio Babino and Alberto Anunziato
On March 28, 2020, between 22 and 22:30 UT, a member of the Sociedad Lunar Argentina observed Mu- tus F, located near the south pole, at the request of the British Astronomical Association and the Lunar Ge- ological Change Detection Program. The requirement stated that “On 2005 Jan 15 at UT 01:25 R. Spellman (Los Angeles, CA, USA, 8" reflector) observed 4 bright points of light on the crater Mutus F? - see Rukl Atlas page 175, chart 74. If his identification of the crater was correct then he could see no structures in the crater that would yield this effect. It could well be that the 4 bright points are just 4 high peaks on the rim catching the first rays of the Sun. The ALPO / BAA weight = 1 ". At the time of the SLA observation we did not know the location of the 4 bright spots that Spellman had observed. We reported to the Lunar Geo- logical Detection Program a sketch indicating a series of bright spots: one on the north rim, another on the southern rim and 3, which could be 4, in the center of the crater: "The bright spots appear to be 3 in the cen- ter of Mutus F (marked 2, 3, and 4). There could be a point between 3 and 4 that I can't resolve. There is a diffuse luminosity that unites points 2, 3 and 4. The central bright spots that seemed peaks of a central mountain range, could not be watched the next day, when the center of the crater was free of shadows and appeared completely devoid of relief.
Intrigued by the luminous points, from the Lunar Section of the Liga Iberoamericana de Astronomía (LIADA) we launched the Lunar Alert LIADA nº 5 in order to get observers observing Mutus F. While we were collecting observations, the May 2020 edition of The Lunar Observer appeared, in which Anthony Cook commented on the SLA observation on page 104, comparing it with the original observation by Rob- ert Spellman (Image 1). Since our telescope has 4 inches, half the size of the telescope with which the origi- nal observation was made, we were unable to resolve the gap between the last two points seen in Spell- man's image, as well as surely what appeared to be a diffuse light between the points in the center of the crater was the difficulty of resolving the bright points. But the disposition of the bright spots between the two observations was the same, and so Cook dismissed the 2005 event as a possible Transient Lunar Phe- nomenon: “As Alberto's sketch (Fig 11 - Center) so closely resembles Robert Spellman's image (Fig 11 - Left) I think we shall lower the weight to 0 and remove it from the LTP database. However, I will keep it on the Lunar Schedule website so that we can figure out what topography are causing points 1-5”.
From the campaign "Lunar Alert LIADA No. 5" an image of the Sociedad Astronómica Octante (Uruguay) was singled out, showing the interior of Mutus F, at a different colongitude and therefore without shadows (image 2). Taking the image to the limit of the possible enlargement (image 3), an area near the northern edge can be seen, which could be the selenographic relief that caused the four bright spots observed by Spellman (and by the SLA with less resolution). The spots indicated as 1 and 5 appear clearly bright in im- age 3 and correspond to bright spots in the Spellman image and the Sociedad Lunar sketch. That area appears to have brighter high spots and darker parts indicating depressions in the terrain. The SAO image was the starting point to hypothetically point to Spellman's bright spots (and points 1 and 5 seen in image 1) in an image taken from the Quick Map of the Lunar Reconaissance Orbiter (image 4), in which they are even seen as a kind of channel, probably overlapping craters. The relief is not high in that area, but could be the cause of the observed bright spots. In “Emergence of low relief terrain from shadow: an explanation for some TLP” (J. Br. Astron. Assoc. 114, 3, 2004) Raffaello Lena and Anthony Cook mention that “the interior of the Ptolemaeus crater displays a “bumpy topography ”Under low solar altitude (-3º), but a classic“ smooth floor ”under a higher solar altitude (> 3º)” and conclude that “small elevations seen under shallow illumination can appear as bright spots”, to give a simple explanation to what seemed like a transitory event. It seems that we are facing the same situation: irregular topography that near the terminator has the appearance of bright spots and that with more frontal light seems completely flat. With a bit of audacity, we attempt an answer to the question from our lunar observation mentor, Dr. Anthony Cook, in the May 2020 issue of TLO: "what topography are causing points 1-5" in Mutus F.
The Lunar Observer/June 2020/ 20
Lunar Geologic Change
Figure I, Mutus F, Left, Robert Spellman, 2005-01-15-0124, Alberto Anunziato, center, 2020-03-28-2200 UT and right 2020-03-29-2225.
Figure 2, Mutus, Sergio Babino, Montevideo, Uru- guay. 2020-04- 29-2310. 8 inch Schmidt- Cassegrain tele- scope, ZWO ASI 174 M camera.
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Lunar Geologic Change
Figure 3, Mutus, Sergio Babino, Montevideo, Uruguay. 2020-04-29-2310. 8 inch Schmidt- Cassegrain telescope, ZWO ASI 174 M camera. (Close up of figure 2).
Figure 4 Mutus, Lunar Reconaissance Orbiter.
The Lunar Observer/June 2020/ 22
East of Nectar Rik Hill
Here we have the east coast of Mare Nectaris. There are some real treats here. The wonderful keyhole shaped crater above center is Gutenberg (77 km) with smaller Gutenberg C (45 km) forming the keyhole shape to the south. To the north are the Rimae Gutenberg looking like three roughly parallel scratch marks heading off to the northwest. Michael Collins got great images from the Apollo 11 command module under the file name AS11-42-6313. Then east of Gutenberg is the oddly shaped crater Goclenius (56 km) with Ri- mae Goclenius stretching from its north wall some 247 km to Gutenberg E (28 km) the broken crater that intrudes on the northeast wall of Gutenberg. Slightly north and to the west on the terminator is the shadow filled craters Capella (51 km). Very dramatic mountains and formations here can be seen as the sun rises further. To the southwest of Gutenberg is a small but interesting crater Guadibert (34 km), just a ring with a central peak here. Further drama is added to this region by the mountainous plateau adjacent to Gutenberg C.
Just south of Goclenius is a mountainous plateau south of Gutenberg C. Further on is a flat floored crater Magelhaens (43 km). A couple hundred kilometers south of Magelhaens is the much larger Columbo (78 km). The craters between them are satellite craters of these two. But the little dark crater north and east (right) of Columbo is a named crater, Bellot (only 17 km!). This whole area is dramatic and always catches the eye when near the terminator.
Gutenberg, Richard Hill, Tucson, Arizona, USA, Loudon Observa- tory. 27 May 2020 0303 UT, colongitude 327.9o. Dynamax 6 telescope with 2 x bar- low, 850 nm filter, Skyris 445M camera. Seeing 7-8/10.
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Recent Topographic Studies
Alphonsus, Abel David Emiliano Gonzalez Cian, AEA - Oro Verde, Entre Rios, Argentina. 02 May 2020 2335 UT. 10 inch Meade Light Bridge telescope, fl 2500 mm. Nikon D3100 cam- era.
Theophilus, Fernando Surá (San Nicolás de los Arroyos, Ar- gentina. 28 April 2020 2212 UT. 127 mm Maksutov- Cassegrain telescope, Blu Cell-Phone.
Online readers, click on images for hyperlinks.
The Lunar Observer/June 2020/ 24
Recent Topographic Studies
Mare Imbrium Lava Flows, Howard Eskildsen, Ocala, Florida, USA. 02 May 2020 0106 UT, colongitude 21.5o. Celestron 9.25 Schmidt- Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M camera. Seeing 7/10, transparency 6/6.
The Lunar Observer/June 2020/ 25
Recent Topographic Studies
Moon, Mars, Saturn and Jupiter conjunction, Gabriel Jaimes, Cochabamba, Bolivia. 15 April 2020 0914 UT. Ga- briel writes “Hoping contribute to your publications and journal, attached you will find some pictures taken from my city, due to lock down from Covid19, sky pollution has significant decreased. Some good news.
8% Waxing Crescent Moon, Jairo Chavez, Popayán, Colombia, SLA-LIADA. 25 April 2020 2326 UT. 114 mm re- fractor telescope, MOTO ES PLAY.
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Recent Topographic Studies
Bayer, Luigi Morrone, Agerola, Italy, SNdR Luna, UAI. 04 May 2020 1936 UT. Celestron 14 Edge Schmidt Cassegrain telescope, Fornax Mount, Baa- der R+IR filter 610 nm, ZWO ASI 178 M camera.
Tycho, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2317 UT. 200 mm refractor telescope, QHY5-II camera.
The Lunar Observer/June 2020/ 27
Recent Topographic Studies
Alpine Valley, Guido Santacana, San Juan, Puerto Rico-USA. 03 April 2020 0157 UT. 150 mm f/12 Maksutov telescope, 2 x barlow, Orion Starshoot 5MP CMOS camera, 200 frames, Registax. Seeing 7/10, transparency 4/6.
Cassini, Francisco Alsina Cardinali, Oro Verde, Ar- gentina, SLA-LIADA. 01 May 2020 2304 UT. 200 mm refractor telescope, QHY5-II camera.
The Lunar Observer/June 2020/ 28
Recent Topographic Studies
Montes Alpes, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 14 April 2019 0248 UT, colongitude 21.1o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Mare Vaporum, Jairo Chavez, Popayán, Colombia, SLA-LIADA. 04 May 2020 0058 UT. 114 mm refractor tele- scope, MOTO ES PLAY.
The Lunar Observer/June 2020/ 29
Recent Topographic Studies
Aristarchus, Michael Sweetman, Tucson, Arizona, USA. Sky Crest Observatory. 05 April 2020 0859 UT. 8-inch Guan Sheng Classical Cas- segrain f/12 , As- tronomik Pro IR 742 nm, Skyris132M cam- era. Seeing 4-5/10, Transparency 3/6. North-right West-up.
Atlas, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2302 UT. 200 mm refractor telescope, QHY5-II camera.
The Lunar Observer/June 2020/ 30
Recent Topographic Studies
Montes Apenninus, Richard Hill, Tucson, Arizo- na, USA, Loudon Observatory. 14 April 2019 0240 UT, colongitude 21.1o. 8 inch f/20 Mak- sutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Maginus, Marcelo Mojica Gundlach, Cochabam- ba, Bolivia. 30 April 2020 2325 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain telescope, ZWO ASI 178 B/N camera. Seeing 7/10, transparency 5/6.
The Lunar Observer/June 2020/ 31
Recent Topographic Studies
Moretus, Luigi Morro- ne, Agerola, Italy, SNdR Luna, UAI. 04 May 2020 UT. Celes- tron 14 Edge Schmidt Cas- segrain tele- scope, For- nax Mount, Baader R+IR filter 610 nm, ZWO ASI 178 M cam- era.
Langrenus, Ste- ve Thornton. 09 May 2020 0821 UT. 9.25 inch Schmidt- Cassegrain tele- scope, 2x bar- low, ZWO ASI 120 nn camera.
The Lunar Observer/June 2020/ 32
Recent Topographic Studies
Plato, Walter Ricardo Elias, AEA - Oro Verde, Entre Rios, Argentina . 01 May 2020 2340 UT. 10 inch Meade LX200 Schmidt-Cassegrain telescope, ZWO ASI 120 mm/ s camera.
Hyginus, Leandro Sid, AEA - Oro Verde, En- tre Rios, Argentina. 01 May 2020 2037 UT. 90 mm Meade Star Navigator NG 90 Mak- sutov-Cassegrain telescope, Samsung J7 Prime camera.
The Lunar Observer/June 2020/ 33
Recent Topographic Studies
Montes Apenninus, Guido Santacana, San Juan, Puerto Rico-USA. 03 April 2020 0159 UT. 150 mm f/12 Mak- sutov telescope, 2 x barlow, Orion Starshoot 5MP CMOS camera, 200 frames, Registax. Seeing 7/10, transparency 4/6.
Online readers, click on images for hyperlinks.
Gemma Frisius, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 06 October 2019 0223 UT, colon- gitude 358.1o. 8 inch f/20 Maksutov Cassegrain tele- scope, 665 nm filter, Skyris 445M camera. Seeing 8/10.
The Lunar Observer/June 2020/ 34
Recent Topographic Studies
Copernicus to Eratosthenes, Richard Hill, Tucson, Arizo- na, USA, Loudon Observato- ry. 14 April 2019 0233 UT, colongitude 21.1o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyr- is 445M camera. Seeing 8/10.
Julius Caesar, Marcelo Mojica Gundlach, Cocha- bamba, Bolivia. 30 April 2020 2324 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain tele- scope, ZWO ASI 178 B/N camera. Seeing 7/10, transparency 5/6.
The Lunar Observer/June 2020/ 35
Recent Topographic Studies
Gassendi, Luigi Morrone, Agerola, Italy, SNdR Luna, UAI. 04 May 2020 1931 UT. Celestron 14 Edge Schmidt Cassegrain telescope, Fornax Mount, Baader R+IR filter 610 nm, ZWO ASI 178 M camera.
Posidonius Richard Hill, Tuc- son, Arizona, USA, Loudon Ob- servatory. 09 July 2019 0248 UT, colongitude 351.3o. 8 inch f/20 Maksutov Cassegrain tele- scope, 610 nm filter, Skyris 445M camera. Seeing 9/10.
The Lunar Observer/June 2020/ 36
Recent Topographic Studies
Tycho, Jairo Chavez, Popayán, Colom- bia, SLA-LIADA. 03 May 2020 0323 UT. 114 mm refractor telescope, MOTO ES PLAY.
Tycho, Ga- briel Jaimes, Co- chabamba, Bolivia. 05 April 2020 1623 UT. 90 mm Bresser re- fractor tele- scope 900 mm fl, Nikon D5600 cam-
The Lunar Observer/June 2020/ 37
Recent Topographic Studies
Messier, Gabriel Re, AEA - Oro Verde, En- tre Rios, Argentina. 01 May 2020 2250 UT. 10 inch Meade LX200 Schmidt-Cassegrain telescope, ZWO ASI 120 mm/s camera.
Theophilus, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 27 May 2020 2325 UT. 90 mm Meade Star Navigator NG 90 Maksutov- Cassegrain telescope, Samsung J7 Prime camera.
The Lunar Observer/June 2020/ 38
Recent Topographic Studies
Lunar size comparison between lunar apogee and perigee, Victor Hugo Cabrera-Peláez, Pue- bla, Mexico. 26 March 2020 2013 UT and 07 April 2020 2137 UT. 120 mm f/8.3 refractor tele- scope, 2.5 x barlow. Seeing 7/10, transparency 4/6.
Victor writes: Comparing the perigee full moon of April 8 at 02:37UT (April 7 at 21:37 UT-5), at a distance of 357,208 km with the moon of March 26 at 01:13 UT (March 26 at 2013 UT-5), at a distance of 406,563 km, only 70000 km closer to the apogee of the previous day, we can note the difference in sizes shown in the image. In each day 25 individ- ual photographs were taken in raw format and HDR processing in ACR of Ps. all images were taken with a Sony A7 camera in a 120mm f/8.3 refractor telescope with a 2.5 Barlow lens at- tached to the camera, with ISO 50. The newborn moon illuminated only 7% with a time of 2.5S and the full moon with a time of 1/100s.
Messier, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2332 UT. 200 mm refractor telescope, QHY5-II camera.
The Lunar Observer/June 2020/ 39
Recent Topographic Studies
Aristarchus to Mairan, Richard Hill, Tucson, Arizona, USA, Loudon Obser- vatory. 12 August 2019 0340 UT, co- longitude 46.8o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 7/10.
Waxing Gibbous Moon, Jairo Chavez, Popayán, Colombia, SLA-LIADA. 01 May 2020 2335 UT. 114 mm refractor telescope, MOTO ES PLAY.
The Lunar Observer/June 2020/ 40
Recent Topographic Studies
Copernicus, Abel David Emiliano Gonzalez Cian, AEA - Oro Verde, Entre Rios, Argentina. 03 May 2020 0220 UT. 10 inch Meade Light Bridge telescope, fl 2500 mm. Nikon D3100 camera.
Licetus to Bossingault, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 06 Octo- ber 2019 0123 UT, co- longitude 355.5o. 8 inch f/20 Maksutov Casse- grain telescope, 610 nm filter, Skyris 665M cam- era. Seeing 8/10.
The Lunar Observer/June 2020/ 41
Recent Topographic Studies
Herschel-Davy-Birt, Howard Eskildsen, Ocala, Florida, USA. 02 May 2020 0111 UT, colongi- tude 21.5o. Celestron 9.25 Schmidt-Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M cam- era. Seeing 7/10, transparency 6/6.
Mare Smythii and Peek, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 12 August 2019 0333 UT, co- longitude 58.4o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 6-7/10.
The Lunar Observer/June 2020/ 42
Recent Topographic Studies
Copernicus, Guido Santacana, San Juan, Puerto Rico-USA. 03 April 2020 0304 UT. 150 mm f/12 Maksutov telescope, 2 x barlow, Orion Starshoot 5MP CMOS camera, 200 frames, Registax. Seeing 7/10, transparency 4/6.
Tycho and Southern Moon, Howard Eskildsen, Oca- la, Florida, USA. 04 May 2020 0044 UT, colongitude 45.7o. Celestron 9.25 Schmidt-Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M camera. Seeing 7/10, transparency 5/6. 4-image composite.
The Lunar Observer/June 2020/ 43
Recent Topographic Studies
Schickard, Luigi Morrone, Agerola, Italy, SNdR Luna, UAI. 04 May 2020 2009 UT. Celes- tron 14 Edge Schmidt Casse- grain telescope, Fornax Mount, Baader R+IR filter 610 nm, ZWO ASI 178 M camera.
Waxing Gibbous Moon, Jairo Chavez, Popayán, Colombia, SLA-LIADA. 03 May 2020 0321 UT. 114 mm refractor telescope, MOTO ES PLAY.
The Lunar Observer/June 2020/ 44
Recent Topographic Studies
Schiller, Luigi Morrone, Agerola, Italy, SNdR Luna, UAI. 04 May 2020 2033 UT. Celestron 14 Edge Schmidt Casse- grain telescope, Fornax Mount, Baader R+IR filter 610 nm, ZWO ASI 178 M camera.
Plato, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2306 UT. 200 mm refractor telescope, QHY5-II camera.
The Lunar Observer/June 2020/ 45
Recent Topographic Studies
Aristoteles to Hercules, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 07 September 2019 0252 UT, colongitude 351.3o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Langrenus, Jairo Chavez, Popayán, Co- lombia, SLA-LIADA. 08 May 2020 0243 UT. 114 mm refractor telescope, MOTO ES PLAY.
The Lunar Observer/June 2020/ 46
Recent Topographic Studies
Aristarchus, Abel David Emiliano Gonzalez Cian, AEA - Oro Verde, Entre Rios, Argentina. 06 May 2020 0008 UT. 10 inch Meade Light Bridge telescope, fl 2500 mm. Nikon D3100 camera.
Lacus Excellentiae, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 18 March 2019 0415 UT, colongi- tude 53.0o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
The Lunar Observer/June 2020/ 47
Recent Topographic Studies
Copernicus Rays, Howard Eskildsen, Ocala, Florida, USA. 04 May 2020 0037 UT, colongi- tude 45.6o. Celestron 9.25 Schmidt-Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M camera. Seeing 7/10, transparency 5/6. 4-image compo- site.
Sinus Iridum, Luigi Morrone, Ager- ola, Italy, SNdR Luna, UAI. 04 May 2020 1943 UT. Celestron 14 Edge Schmidt Cassegrain telescope, For- nax Mount, Baader R+IR filter 610 nm, ZWO ASI 178 M camera.
The Lunar Observer/June 2020/ 48
Recent Topographic Studies
Barrow, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 06 October 2019 0123 UT, colongitude 348.1o. 8 inch f/20 Maksutov Cas- segrain telescope, 610 nm filter, Skyris 445M cam- era. Seeing 8/10.
Tycho, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2316 UT. 200 mm refractor telescope, QHY5-II camera.
The Lunar Observer/June 2020/ 49
Recent Topographic Studies
Gassendi, Richard Hill, Tucson, Arizo- na, USA, Loudon Obser- vatory. 18 March 2019 0407 UT, co- longitude 52.9o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyr- is 445M cam- era. Seeing 8/10.
Online readers, click on images for hyperlinks.
Vallis Alpes, Marcelo Mojica Gundlach, Cochabam- ba, Bolivia. 30 April 2020 2330 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain tele- scope, ZWO ASI 178 B/N camera. Seeing 7/10, trans- parency 5/6.
The Lunar Observer/June 2020/ 50
Recent Topographic Studies
Cassini and Caucasus, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 06 Oc- tober 2019 0130 UT, colongitude 355.8o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Tycho Jairo Chavez, Popayán, Colombia, SLA-LIADA. 01 May 2020 2325 UT. 114 mm refractor telescope, MO- TO ES PLAY.
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Recent Topographic Studies
Hadley Rille, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 14 April 2019 0246 UT, co- longitude 21.1o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. See- ing 8/10.
Full Moon, Jairo Chavez, Popayán, Co- lombia, SLA-LIADA. 08 May 2020 0257 UT. 114 mm refractor tele- scope, MOTO ES PLAY.
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Recent Topographic Studies
Clavius, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 17 March 2019 0338 UT, colongitude 39.8o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Hyginus, Marcelo Mojica Gundlach, Cochabamba, Bolivia. 30 April 2020 2321 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain telescope, ZWO ASI 178 B/N camera. Seeing 7/10, transparency 5/6.
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Recent Topographic Studies
Cassini, Aristillus and Autolycus Marcelo Mo- jica Gundlach, Cochabamba, Bolivia. 30 April 2020 2320 UT. 180 mm, fl 1,800 mm Sky- Watcher Maksutov-Cassegrain telescope, ZWO ASI 178 B/N camera. Seeing 7/10, transparen- cy 5/6.
Mare Australe, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 14 May 2019 0247 UT, colongitude 27.0o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8-9/10.
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Recent Topographic Studies
Ramsden, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 17 March 2019 0350 UT, colongitude 39.8o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Langrenus, Francisco Alsina Cardi- nali, Oro Verde, Argentina, SLA- LIADA. 01 May 2020 2210 UT. 200 mm refractor telescope, QHY5-II cam- era.
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Recent Topographic Studies
Alphonsus, Marcelo Mojica Gundlach, Cochabamba, Bolivia. 30 April 2020 2331 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain telescope, ZWO ASI 178 B/N camera. Seeing 7/10, transparen- cy 5/6.
Maurolycus Marcelo Mojica Gundlach, Cochabam- ba, Bolivia. 30 April 2020 2324 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain tele- scope, ZWO ASI 178 B/N camera. Seeing 7/10, transparency 5/6.
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Recent Topographic Studies
Thebit, Richard Hill, Tucson, Arizona, USA, Loudon Obser- vatory. 07 Oc- tober 2019 0142 UT, co- longitude 9.0o. 8 inch f/20 Maksutov Cas- segrain tele- scope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Taruntius, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2335 UT. 200 mm refrac- tor telescope, QHY5-II camera.
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Recent Topographic Studies
Marius, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 18 March 2019 0438 UT, colongitude 52.2o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
Petavius, Steve Thornton. 09 May 2020 0812 UT. 9.25 inch Schmidt-Cassegrain telescope, 2x barlow, ZWO ASI 120 nn cam- era.
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Recent Topographic Studies
Waxing Gibbous Moon, Jairo Chavez, Popayán, Colombia, SLA-LIADA. 04 May 2020 2341 UT. 114 mm refractor telescope, MOTO ES PLAY.
Serpentine Ridge, Howard Eskildsen, Ocala, Flori- da, USA. 28 May 2020 0037 UT, colongitude 338.7o. Celestron 9.25 Schmidt-Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M camera. Seeing 7-8/10, transparency 5/6.
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Recent Topographic Studies
Bessel, Marcelo Mojica Gundlach, Cochabamba, Bolivia. 30 April 2020 2324 UT. 180 mm, fl 1,800 mm Sky- Watcher Maksutov-Cassegrain telescope, ZWO ASI 178 B/ N camera. Seeing 7/10, transparency 5/6.
Lamont, Howard Eskildsen, Ocala, Flori- da, USA. 28 May 2020 0040 UT, colongi- tude 338.8o. Celestron 9.25 Schmidt- Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M camera. Seeing 7-8/10, trans- parency 5/6.
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Recent Topographic Studies
Ross D, Francisco Alsina Cardinali, Oro Verde, Argentina, SLA-LIADA. 01 May 2020 2340 UT. 200 mm refractor telescope, QHY5-II camera.
Hyginus N, Aylen Borgatello, AEA - Oro Verde, Entre Rios, Argentina. 01 May 2020 2331 UT. 10 inch Meade LX200 Schmidt-Cassegrain telescope, ZWO ASI 120 mm/s camera.
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Recent Topographic Studies
Online readers,
click on images for hyperlinks.
Mare Fecunditatis and Western Chain, Howard Eskildsen, Ocala, Florida, USA. 28 May 2020 0040 UT, colongitude 338.8o. Celestron 9.25 Schmidt- Cassegrain telescope, f/10, fl 2395 mm, Skyris 236M camera. Seeing 7-8/10, transparency 5/6.
"Western Chain" and Fecunditatis
This two-image composite shows the "Western Chain" of craters: Langrenus, Vendelinus, Peta- vius, and Furnerius. Of course, it is now on the eastern Moon since the Apollo-era convention change. These craters of vastly different ages form a notable chance arrangement that was once used as an argument for the endogenic origin of craters. They were then thought to trace a deep fault line that allowed the "eruptions" that supposedly formed the craters. Then along came Dr. Ralph Baldwin who proved lunar craters to be from impacts, not eruptions. His work was later supported by the lunar samples from Apollo.
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Recent Topographic Studies
Aristoteles, Marcelo Mojica Gundlach, Cochabamba, Bolivia. 30 April 2020 2323 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain telescope, ZWO ASI 178 B/N camera. Seeing 7/10, transparency 5/6.
Copernicus, Walter Ricar- do Elias, AEA - Oro Verde, Entre Rios, Argentina . 01 May 2020 2351 UT. 10 inch Meade LX200 Schmidt -Cassegrain telescope, ZWO ASI 120 mm/s cam- era.
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Recent Topographic Studies
Mare Smythii, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 27 September 2017 0338 UT. 8 inch f/20 Maksutov Cassegrain telescope, 665 nm filter, Skyris 445M camera. Seeing 7/10.
Rima Hyginus, Marcelo Mojica Gundlach, Cocha- bamba, Bolivia. 30 April 2020 2337 UT. 180 mm, fl 1,800 mm Sky-Watcher Maksutov-Cassegrain tele- scope, ZWO ASI 178 B/N camera. Seeing 7/10, trans- parency 5/6.
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Recent Topographic Studies
Alphonsus, Walter Ricardo Eli- as, AEA - Oro Verde, Entre Rios, Argentina . 01 May 2020 2221 UT. 10 inch Meade LX200 Schmidt-Cassegrain tele- scope, ZWO ASI 120 mm/s cam- era.
Mons La Hire, Aylen Borgatello, AEA - Oro Verde, Entre Rios, Ar- gentina. 02 May 2020 0158 UT. 10 inch Meade LX200 Schmidt- Cassegrain tele- scope, ZWO ASI 120 mm/s cam- era.
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Recent Topographic Studies
Gassendi, Michael Sweetman, Tucson, Ari- zona, USA. Sky Crest Observatory. 05 April 2020 0842 UT. 8-inch Guan Sheng Classical Cassegrain f/12 , As- tronomik Pro IR 742 nm, Skyris132M camera. Seeing 4-5/10, Transpar- ency 3/6. North-left, West-down.
Hainzel, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 17 March 2019 0342 UT, colongitude 39.8o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8/10.
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Recent Topographic Studies
Plato, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 01 May 2020 2051 UT. 90 mm Meade Star Navigator NG 90 Maksutov- Cassegrain telescope, Samsung J7 Prime camera.
Tycho, Walter Ricardo Elias, AEA - Oro Verde, Entre Rios, Argentina . 01 May 2020 2344 UT. 10 inch Meade LX200 Schmidt-Cassegrain telescope, ZWO ASI 120
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Recent Topographic Studies
Copernicus, Walter Ricardo Elias, AEA - Oro Verde, En- tre Rios, Argentina . 02 May 2020 0101 UT. 10 inch Meade LX200 Schmidt- Cassegrain telescope, ZWO ASI 120 mm/s camera.
Tycho, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 01 May 2020 2054 UT. 90 mm Meade Star Navigator NG 90 Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Kepler, Walter Ricardo Elias, AEA - Oro Verde, Entre Rios, Argentina . 11 May 2020 1016 UT. 10 inch Meade LX200 Schmidt-Cassegrain tel- escope, ZWO ASI 120 mm/s camera.
Atlas, Aylen Bor- gatello, AEA - Oro Verde, Entre Rios, Argentina. 02 May 2020 0115 UT. 10 inch Meade LX200 Schmidt-Cassegrain telescope, ZWO ASI 120 mm/s camera.
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Recent Topographic Studies
Torricelli B, Gabri- el Re, AEA - Oro Verde, Entre Rios, Argentina. 01 May 2020 2228 UT. 10 inch Meade LX200 Schmidt- Cassegrain tele- scope, ZWO ASI 120 mm/s camera.
Copernicus, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 03 May 2020 0220 UT. 90 mm Meade Star Navi- gator NG 90 Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Waning Gibbous Moon, Walter Ricardo Elias, AEA - Oro Verde, Entre Rios, Ar- gentina . 13 May 2020 1027 UT. 10 inch Meade LX200 Schmidt -Cassegrain telescope, Canon Rebel T7i cam- era.
Alphonsus, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 02 May 2020 2318 UT. 90 mm Meade Star Navi- gator NG 90 Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Apennines, Antonio Polo. 30 May 2020 1758 UT.
Aristarchus, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 10 May 2020 0027 UT. 90 mm Meade Star Navigator NG 90 Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Full Moon, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 08 May 2020 0044 UT. 90 mm Meade Star Navigator NG 90 Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
Waning Gibbous Moon, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 10 May 2020 0130 UT. 90 mm Meade Star Navigator NG 90 Maksutov- Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Daniell, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 27 May 2020 2254 UT. 90 mm Meade Star Navigator NG 90 Maksutov- Cassegrain telescope, Samsung J7 Prime camera.
Messier, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 27 May 2020 2317 UT. 90 mm Meade Star Navigator NG 90 Maksutov- Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Picard, Walter Ricardo Elias, AEA - Oro Verde, Entre Rios, Argentina . 10 May 2020 0206 UT. Meade Star Navigator NG90 mm Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
Posidonius, Leandro Sid, AEA - Oro Verde, En- tre Rios, Argentina. 10 May 2020 0215 UT. 90 mm Meade Star Navigator NG 90 Maksutov- Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Menelaus, Leandro Sid, AEA - Oro Verde, Entre Rios, Argentina. 28 May 2020 2250 UT. 90 mm Meade Star Navi- gator NG 90 Maksutov-Cassegrain telescope, Samsung J7 Prime camera.
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Recent Topographic Studies
Petavius to Humboldt, Richard Hill, Tucson, Arizona, USA, Loudon Observatory. 14 May 2019 0240 UT, colongi- tude 27.0o. 8 inch f/20 Maksutov Cassegrain telescope, 610 nm filter, Skyris 445M camera. Seeing 8-9/10.
Aristarchus and Vallis Schroteri, Luigi Morrone, Agerola, Italy, SNdR Luna, UAI. 04 May 2020 1957 UT. Celes- tron 14 Edge Schmidt Cassegrain telescope, Fornax Mount, Baader R+IR filter 610 nm, ZWO ASI 178 M camera.
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Lunar Geologic Change Detection Program Coordinator Dr. Anthony Cook- [email protected] Assistant Coordinator David O. Darling [email protected]
2020 June
LUNAR GEOLOGICAL CHANGE DETECTION PROGRAM
Reports have been received from the following observers for Apr: Jay Albert (Lake Worth, FL, USA - ALPO) observed: Alphonsus, Bullialdus, Censorinus, Copernicus, Eimmart, Gassendi, Messier, Plato and Torricelli B. Alberto Anunziato (Argentina - SLA) observed: Alphonsus, Aristarchus, Bullialdus, Eimmart and Schickard. Bruno Cantarella (Italy – UAI) imaged Mons Piton. Maurizio and Francesca Cecchini (Italy – UAI) imaged Mons Piton and Tycho. Abel Cian (Argentina – AEA) imaged Aristarchus and several feature. Maurice Collins (New Zealand – ALPO/BAA/RASNZ) imaged: Alphonsus, Aristarchus, Archimedes, Mare Serenitatis, Theophilus and several features. Tony Cook (ALPO/BAA) videoed the Moon in the thermal IR and imaged several features in visible to near-IR wavebands. Walter Elias (Argentina – AEA) imaged: Plato and several features. Valerio Fontani (Italy – UAI) imaged: Mersenius C, Mons Piton, Tycho and the Full Moon. Les Fry (Mid-Wales, UK – NAS) imaged: Aristarchus, Copernicus, Mare Humorum, Mare Imbrium and Schickard. Rik Hill (Tucson, AZ, USA - ALPO/BAA) imaged Apianus, Clavius, Copernicus and several features. Bill Leatherbarrow (Sheffield, UK – BAA) imaged: Riccioli. Jean Marc Lechopier (France – UAI) imaged: Mersenius C and Mons Piton. Nigel Longshaw (Oldham, UK - BAA) observed: Lichtenburg. Leo- nardo Mazzei (Italy – UAI) imaged earthshine. Trevor Smith (Codnor, UK – BAA) observed: Aristarchus, Bullialdus, Censorinus, Lichtenburg, Manilius, Plato, Proclus, Timocharis, Torricelli B, Vallis Schroteri, and several features. Bob Stuart (Rhayader, UK – BAA/NAS) imaged: Aristarchus, Bettinus, Hevelius, Mare Crisium, Schickard, and several features. Franco Taccogna (Italy – UAI) imaged: the Full Moon. Aldo To- non (Italy – UAI) imaged: Mins Piton and the Full Moon. Gary Varney (Pembroke Pines, FL, USA – ALPO) imaged: Plato and Tycho. Fabio Verza (Italy – UAI) imaged: Mersenius C, Mons Piton, and Tycho. Luigi Zanatta (Italy – UAI) imaged: earthshine and Mons Piton.
LTP reports: No LTP were reported in April, although I did receive a report from Phil Shepherdson (York, UK – BAA) concerning an “ashen” sliver of light seen across the floor of Ptolemaeus on 2020 Feb 01 UT 19:40-19:50. Having studied this area for many years, both myself and the director of the BAA Lunar Section strongly suspected that these were the normal shadow spires at sunrise. However, Phil re-observed on 2020 May 29 UT 23:45-00:13 and could not see the “ashen” effect. The effect seen back in Feb may have any number of reasons, such as seeing, transparency, and even condensation on the optics, but for safety we shall put this as a weight 1 LTP in the ALPO/BAA database, just so that we may get used to a series of ob- servations under a variety of observing conditions to see if we can replicate what Phil saw.
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Figure 1. Riccioli orientated with north towards the top. (Left) A monochrome IR image by Bill Leatherbarrow (BAA Lunar Section Director) taken on 2020 Apr 06 UT 22:25. (Right) An image by Anthony Cook (ALPO/BAA) taken on 2020 Apr 07 UT 01:00. This has been color normalized and then had its color saturation increased.
On 2020 Apr 06/07 I was videoing the Moon with a color webcam coupled to a x2 Barlow. This was picking up some color such as the blueness of Aristarchus, which is normal. What I was not expecting was to see some green/brown covering the crater Riccioli (Fig 1 – Right). An email, from Bill Leatherbar- row, revealed that he had imaged the area earlier in the near-IR (Fig 1 – Left) – so although not confirming the color, is at least of higher resolution. Another email from Nigel Longshaw (BAA), reminded me that color in Riccioli is mentioned in Walter Haas’: “Does anything ever happen on the Moon?”. Walter says that observers have noted a greenish tint on the floor of c at sunrise, but purplish grey with a tinge of brown at other times – even a deep purple has been recorded. I will add this to the Lunar Schedule web site so that we can confirm this. Incidentally the LROC WAC mosaic does not exhibit a green tinge here, so the color seems to be a directional effect and perhaps maybe associated with draping of Hevelius formation ejecta from Mare Orientale? Perhaps the thickness of any overlying Hevelius Formation material may vary de- pending upon what the slope angle and direction of the underlying topography is like and the emplacement approach angle of the original ejecta?
Routine Reports: Below are a selection of reports received for April that can help us to re-assess unusual past lunar observations – if not eliminate some, then at least establish the normal appearance of the surface features in question.
Archimedes: On 2020 Apr 01 UT 07:12 and 07:31 Maurice Collins (ALPO/BAA/RASNZ) imaged this crater under similar illumination (±0.5°) to the following report:
Archimedes 1966 Mar 29 UT 21:00 Observed by Hill (England, 24" reflector, x250, S=E) "Brightening of E-W bands across floor. (Obscuration accord. to Moore)" NASA catalog ID #923. NASA catalog weight=3. ALPO/BAA weight=1.
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Figure 2. Archimedes as imaged by Maurice Collins (ALPO/BAA/RASNZ), on 2020 Apr 01, contrast stretched and orientated with north towards the top. (Left) Image taken at 07:12UT. (Right) Image taken at 07:31UT.
Maurice has certainly picked up the shadow bands on the floor of Archimedes and you can see an apparent change as the Sun rises (Fig 2) and there is a clear brightening. However, I would not describe this as an obscuration. Unfortunately, I don’t have the original observations, so this must stay at a low weight of 1 for now.
Tycho: On 2020 Apr 01 UAI observers: Maurizio and Francesca Cecchini, Valerio Fontani, and Fabio Ver- za, monitored this crater (Fig 3) between 19:03 and 19:46UT under a colongitude range of 12.5° to 12.8º as specified in the following Lunar Schedule request:
BAA Request: How early can you see the central peak of this crater illuminated by scattered light off the crater's west illuminated rim? High resolution and/ or long exposures needed to capture detail inside the floor shadow. All images should be sent to me on the email address below, whether or not you were suc- cessful in capturing the central peak: a t c @ a b e r . a c. u k
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Figure 3. Tycho orientated with north towards the top and contrast stretched. (Top Left) An image by Brendan Shaw taken on 2003 May 09 UT 21:04 (Col.=12.6°, Latʘ=-0.3º, Azʘ=89.3º, Altʘ=1.2º), using a 3” Takahashi refractor, showing the central peak, despite being in shadow. (Top Right) An image taken by Fabio Verza (UAI) on 2020 Apr 01 UT 19:03 (Col.=12.5°, Latʘ=-1.5º, Azʘ=90.2º, Altʘ=2.0º), using a Celestron CPC800 scope through an IR807 filter. (Center Right) Image taken by Valerio Fontani on 2020 Apr 01 UT 19:15 (Col.=12.7°, Latʘ=-1.5º, Azʘ=90.1º, Altʘ=2.1º) using a Meade LX200 telescope with a red filter. (Bottom) Image taken by Maurizio and Francesca Cec- chini (C14 XLT telescope, 630nm Astronomik red filter, seeing 5-6/10) on 2020 Apr 01 UT 19:32 (Col.=12.5°, Latʘ= -1.5º, Azʘ=90.2º, Altʘ=2.0º) with a brightness cross-section profile taken through the shadowed area of the floor.
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We have covered this LTP before in the 2011 Aug, 2014 Oct, and 2016 Mar newsletters. Interest- ingly the original sighting of the central peak, by Brendan Shaw back in 2003 (Fig 3 – Top Left) was at a much lower solar altitude than the UAI team were observing at, and seems to have been more prominent, and made with a smaller instrument. Only the Cecchini observation (Fig 3 – bottom), made with a 14”, just about detected the peak. The solar altitude is too low for direct illumination, so most probably is being illu- minated by reflection of light off of the western rim. The puzzle is why was the central peak so bright back in 2003 but hard to detect in the UAI observations, and similarly problematic to detect at a solar altitude of 1.2º?
Mons Piton: On 2020 Apr 01 UAI observers observed for the following Lunar Schedule request:
BAA Request: Can you see a point of light emerging from the shadow of this mountain? Any sketches, visual descriptions, or images taken, should be emailed to: a t c @ a b e r . a c. u k .
Figure 4. Mons Piton orientated with north towards the top. (Far Left) An image by Luigi Zanatta (UAI) taken on 2020 Apr 01 UT 19:40. (Left) An image taken by Fabio Verza (UAI) taken on 2020 Apr 01 UT 29:30. (Center) An image by Valerio Fontani (UAI) taken on 2020 Apr 01 UT 20:36. (Right) An image by Aldo Tonon made on 2020 Apr 01 UT 20:50. (Far Right) A sketch by Trevor Smith (BAA) Made on 2019 Nov 05 UT 20:10.
This actually corresponds to a 2004 Jan 30 UT 15:52 LTP report from some unknown Italian LTP observer. I think I recall at the time that I was in discussion with Raffaello Lena (GLR) and we both agreed that it was probably an isolated peak on the slopes of Mons Piton. Our four UAI observers show the peak effect quite nicely in Figs 4 (Far Left – Right). In addition, I recalled that we had a sketch by Trevor Smith (Fig 4 – Far Right) that shows the same effect. Having investigated the mountain in LROC images, and seen later images by the UAI, we can definitely be sure that this is topography sticking out of the shadow and can now safely remove this LTP from both the Lunar Schedule website and the LTP website.
Plato: On 2020 Apr 03 UT 00:53 Gary Varney (ALPO) imaged the crater at similar illumination (±0.5º) to the first report below, and 41min prior to the second report. Jay Albert (ALPO) observed from 01:25-01:50 UT, some 27 min after the end of the first observing window but during the second:
Plato 2005 Dec 10 UT 20:46 Observed by Brook (Plymouth, UK, 4" refractor. Con- ditions excellent with the Moon at a high altitude) "2 second duration white flash seen on the floor of the crater" - BAA Lunar Section Report.
On 1980 Apr 24 at 23:35UT Marco Petek (Porto Alegre, Brazil, using a 7.5" re- fractor noticed that the center of Plato was bright and opaque and the observ- er thought it was similar in appearance to Linne. A sketch was made and two other observers confirmed the appearance. Cameron mentions that Petek is an experienced observer. Cameron 2006 catalog extension LTP ID=91 and weight=5. ALPO/BAA weight=3.
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Figure 5. Plato orientated with north towards the top. (Left) Image by Brendan Shaw taken on 2005 – note the black dot on the floor of Plato is a dust speck in the camera system. (Center Top) An electronic sketch by Clive Brook on 2005 Dec 10 UT 20:46. (Center Bottom) A sketch by Petek on 1980 Apr 24 UT 23:35. (Right) An image by Gary Varney on 2020 Apr 03 UT 01:53.
Jay comments that the crater was mostly sunlit with some shadow remaining along the inner E wall. The floor was lacking in detail and only the central craterlet was sometimes visible. The crater floor seemed brighter than usual in comparison with Mare Frigoris and Mare Imbrium. A very faint, very slight- ly darker, indistinct dusky band ran E-W across the N part of the crater floor. No color or brightness varia- tions were observed. A hand-held iPhone image was taken (Not shown here). Plato was observed from 01:25 to 01:50UT at 290x and rechecked from 02:05 to 02:15UT with no sign of change. We shall leave both weights as they are.
Plato: On 2020 Apr 04 UT 02:15-02:30 Jay Albert (ALPO) observed and 02:43UT Walter Elias (AEA) imaged the crater under similar illumination to the following 1960’s era report:
Plato 1966 Dec 23 UT 06:15-07:10 Observed by Kelsey (Riverside, CA, USA, 6" reflector, S=P, T=G) and Coralitos Observatory (Organ Pass, NM, USA, 24" re- flector + Moonblink) "3 brilliant spots on floor, all showed blinks, (permanent colored Ground features ?). Not confirmed by Corralitos MB." NASA catalog weight=2. NASA catalog ID #1005. ALPO/BAA weight=1.
Figure 6. (Top) A section from the BAA Lunar Section Circular from Vol No. No. 4, p9 – the only evidence we have of the 1966 LTP report from H.W. Kelsey. (Bottom) A repeat illumination image of Plato taken by Walter Elias (AEA) on 2020 Apr 04 UT 02:43, and orientated with north towards the top.
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Jay noted that he didn’t see the “3 brilliant spots on floor”. Actually, there were no brilliant spots at all on the floor. He saw the dim central craterlet and sometimes saw the S craterlet with difficulty. The N pair of craterlets was not seen. The crater floor was darker than the previous night and clearly darker than Frigoris and Imbrium. He used 290x from 02:15 to 02:30UT. Walter’s image (Fig 6 - bottom) confirms Jay’s account that there were no signs of 3 brilliant spots on the floor. Interestingly all we have on the Kel- sey report is the BAA Lunar Section report (Fig 6 – Top). Is it possible that local time was given for Kel- sey’s location: Riverside, California, USA? We shall leave the weights of both LTP reports as they are for the moment.
Eimmart: on 2020 Apr 03/04 23:30-23:40 UT Alberto Anunziato (SLA) and 01:06-01:22 UT Jay Albert (ALPO) observed visually this crater under similar illumination to the following report:
On 1981 Apr 15 at UT06:27-06:40 D. Louderback (South Bend, WA, USA using a 3" refractor x134 and S=4.5-5 and T=5-0) saw a bright spot on the western wall of Eimmart (sketch supplied) have an unusual brightening and shade. Variations occurred over 2-3-minute intervals. Louderback commented that the spot looked like a flare with its apex located at the crater wall and there was some blur- ring effect on the spot - it decreased in size during the phenomenon. Seeing worsened later. Apparently on the 18th and 19th of April everything was back to normal. Cameron comments that there is no bright spot on the Moon at this location. Lunar Orbiter IV plates 192-3.2 shows evening conditions. Cameron 2006 Catalog Extension LTP ID=130 and weight=3. ALPO/BAA weight=3.
Figure 7. The bright spot on the western wall of Eimmart crater as sketched by Alberto Anunziato (SLA) on 2020 Apr 03 UT 23:30-23:40. This sketch has been reoriented so that north was towards the top and labels adjusted accord- ingly.
Alberto made a sketch (Fig 7) of the appearance of Eimmart (shadings inverted). The crater was very bright, with some zones brighter than the rest (to the east) marked as darker in the sketch. Only Proclus appeared brighter in the Mare Crisium. Jay comments that there was a bright spot on the W wall of the crater. The entire crater was lit up very brightly, was much foreshortened near the limb and was not at all sharp. The spot on the W wall was a brilliant white and stood out like a flare. There was some seeing- related image movement, but the intense brightness didn’t seem to vary. An image taken by Walter Elias (AEA) at 23:44UT, but not shown here as the area is quite small in the image, also reveals the bright spot. We shall therefore lower the ALPO/BAA weight of this report 3 to 1 because there is normally a bright spot here, despite what Cameron says. The variations seen in 1981 are probably seeing related, but we shall have one further repeat illumination round of observing to check out this theory of Jay’s.
Bullialdus: On 2020 Apr 04 UT 21:53-22:19 Trevor Smith (BAA) observed visually during the following repeat illumination (±0.5°) window, and at 20:52 UT Les Fry (NAS) imaged Mare Humorum just 36 min prior to the start of the window:
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2006 Dec 02 at 03:30UT observer noticed a hint of yellow color on the floor of the crater and by 03:57UT the south east and central parts of the floor and the circular feature on the south west floor had turned a deep yellow color. The rest of the crater remained colorless. Other craters also remained color- less. By 04:05UT the color was fading and by 04:15UT it was gone. Maurice Col- lins in New Zealand took some low-resolution color images about 4 hours later but these failed to show any yellow color. Zac Pujic obtained color images at a different time of natural surface color on the Moon and finds that Bulli- aldus does actually have a natural yellow cast to most of the floor. However, this does not explain the variability in color strength seen by Robin Gray. ALPO/BAA weight=3.
Figure 8. Bullialdus orientated with north towards the top. (Left) A sketch by Robin Gray made on 2006 Dec 02 UT 03:30-05:18 using a 152mm f/9 refractor at x228, seeing 5, transparency 3-6. (Right) A color image by Les Fry (NAS) which has been color normalized and then had its color saturation increased to 50%.
Trevor, using a 16” Newtonian at x247, stated that the crater looked normal with no yellow glows, no haze, nor any spurious color (atmospheric spectral dispersion). He found the central peaks easy to see, as was other detail. Although the image from Les was before the similar illumination prediction, you can quite clearly see that at the locations where Robin Gray wrote “Y” for yellow (Fig 8 – Left), there is no obvious signs of yellow on the floor in Les’ image (Fig 8 – Right). Despite the fact that apparently you can see color here at a different illumination, because Les’ image does not show any yellow, I think we shall have to leave the weight of the TLP at 3 for now.
Mersenius C: On 2020 Apr 04, UAI observers: Valerio Fontani, Jean Marc Lechopier, and Fabio Verza, imaged the Moon under similar selenographic colongitudes (50.4° to 50.8°) to the following Lunar Sched- ule web site request:
ALPO Request: Color images or visual inspection needed of the area just SW of this crater. If taking images, do not over expose on bright slopes. Can you detect any natural surface color here or mistiness? Minimum aperture needed 4", and if you have a choice, use a refractor instead of a reflector. Please send any images, or sketches, to: a t c @ a b e r . a c. u k
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Figure 9. The region around Mersenius C, orientated with north towards the top. (Top Left) 2005 Nov 12 UT 04:48 image by Wayne Bailly – color normalized image (Col.=50.6°, Azʘ=89.4º, Altʘ=4.3º). (Top Center) A annotated im- age by Glen Ward (LPO) showing where they saw a light green glow on 2005 Nov 12 UT 04:30-04:57 (Col.=50.6°, Azʘ=89.4º, Altʘ=4.4º). (Top Right) 2020 Apr 04 UT 22:02 color image, by Fabio Verza (UAI) which has been color normalized and then had its color saturation increased to 75% (Col.=50.5°, Azʘ=89.9º, Altʘ=4.5º). (Bottom Left) 2020 Apr 04 UT 22:14 color by Valerio Fontani (UAI) which has been color normalized and had its color saturation increased to 30% (Col.=50.6°, Azʘ=89.9º, Altʘ=4.6º). (Bottom Right) 2020 Apr 04 UT 22:32 (UAI) monochrome image by Jean Marc Lechopier (UAI) (Col.=50.8°, Azʘ=89.8º, Altʘ=4.7º).
This ALPO request for observation actually refers to a 2005 Nov 12 UT 04:50-04:57 observation by Glen Ward, where a light green color was seen on a mountain SW of Mersenius (See Fig 9 – Top Center). We covered this before in the 2020 April newsletter, so its welcome to see some additional images to add to our arsenal of evidence as to what the area should normally look like. Wayne Bailly, who obtained video just prior to the onset of the Ward observation, has very kindly sent me a copy of his original color video. I have examined this carefully, and although still hindered by the glare (saturated pixels) from the bright sun- lit slope where Glen Ward saw color, I cannot see any color in the immediate surrounds which isn’t similar to color associated with other bight saturated areas elsewhere in the image. So alas inconclusive about con- firming/disproving Glen’s report – but at least we have the original video now which can always be re- examined using improved future techniques. Moving onto the UAI similar selenographic colongitude imag- es, Fig 9 (Top Right, Bottom Left and Bottom Right), in Valerio’s image (Fig 9 – Top Right), there is per- haps a very slight hint of turquoise blue/lime green in the location of the 2005 LTP, but it is by no means unique because if you look at other bright peak locations, you can sometimes see a similar effect. It may be due to telescope chromatic aberration (always present to some extent where you have glass in the optics, even the camera window) or something to do with the camera (if it is of a Bayer matrix type?). It might also just be natural color as geologically young slopes tend to be bluer. I will leave the weight of the original report at 3, but change the request on the Lunar Schedule web site so that we stick to larger apertures with color cameras. I may also tighten up the libration requirements so that the viewing angle is similar – in case it is something unusual like internal reflection from pyroclastic glass beads on the surface causing the color Glen saw back in 2005?
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Lichtenberg: On 2020 Apr 06/07 three BAA members: Nigel Longshaw (22:00-22:25, 23:00-23:36 UT), Trevor Smith (22:40 & 23:30 UT) and Anthony Cook (00:38-00:40UT) studied this crater under both simi- lar illumination and topocentric libration (±1º) to the following past LTP report:
Lichtenberg 1951 Jan 21 18:19.2-18:38.5 UT observed by Baum (Chester, Eng- land). Tiny red spot noticed initially and then faded. Location of spot 31.403N 66.167W. 20cm refractor x90-x100. Seeing fair-extremely good. NASA catalog assigns a weight of 3. NASA LTP ID No. #542. ALPO/BAA weight=2.
Figure 10. Lichtenberg orientated with north towards the top. (Left) A sketch by Nigel Longshaw (BAA) made on 2020 Apr 06 UT 22:00-22:25. (Center) A CCD image captured by Anthony Cook (ALPO/BAA) made on 2020 Apr 07 UT 00:38-00:40. (Right) A sketch by Richard Baum (BAA) made on 1951 Jan 21 UT 18:19-18:38.
Trevor reported seeing no tiny red spot at either of the times he observed despite using a 16” Newto- nian. Nigel made a sketch (Fig 10 – Left) and noted a very slight pink and red color (perhaps even reddish/ brown grey?) to the dark region N/S and E of the crater. This became more pronounced at 23:36UT. Note that I have summarized Nigel’s detailed notes here quite considerably. My own image (Fig 10 - center) has red coloration to the W/N & S of the crater – different to what Nigel saw visually? It is interesting that Richard Baum’s sketch (Fig 10 – Right) has relatively little shadow inside the crater compared to Nigel’s sketch and my own image. This might suggest a date error in Richard’s log book? We shall keep the LTP weight as it is but will add a date of one day later in the Lunar Schedule web site.
The Full Moon: On 2020 Apr 07 UAI observers (Aldo Tonon, Valerio Fontani, and Franco Taccogna) im- aged the whole lunar disk to help with a lunar schedule request:
ALPO Request: Please take images of the Full Moon, but make sure you under ex- pose as we want to avoid bright ray craters like Aristarchus, Tycho, Proclus etc from saturating. The purpose behind this is we want to compare with images of Earthshine which are essentially zero phase illumination images, like at Full Moon. There have been reports in the past that Aristarchus varies greatly in brightness compared to other features. David Darling (a past LTP coordina- tor) has suggested this was simply due to libration effects, i.e. viewing an- gles, so we would naturally like to test this theory out. Also, if you have any past images of close to Full Moon, please send these in too if the above- mentioned craters are not saturated. Pretty much any size telescope can be used to take these images so long as we can clearly see the above craters. Ob- viously do not attempt this if the sky is cloudy or hazy. Observations will be presented in the "Lunar Observer" - a monthly publication of the Lunar Section of ALPO. All reports should be emailed to: a t c @ a b e r . a c . uk
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Table 1. Relative brightness measurements of different lunar features made using images taken on 2020 Apr 07.
Table 1 summarizes the relative brightness of some selected features. It clearly shows that Aristar- chus was not the brightest feature on the Moon that night, instead Proclus or Hell were. There is some vari- ability in the ordering – this is caused by image resolution and relative sizes of features. The more point- like/compact the features are the more they will be affected by image resolution. We will be using Full Moon data such as this for a study in the future on how libration affects the relative brightness of features at Full Moon.
Aristarchus: On 2020 Apr 18 IUT 09:15 Abel Cian (AEA) imaged this crater under similar illumination to the following events:
Aristarchus 1787 Oct 07 UT 03:00? Observed by Schroter (Lileinthal, Germany). Cameron 1978 catalog weight=1. Cameron 1978 catalog ID=36. ALPO/BAA catalog weight=1.
Figure 11. Aristarchus on 2020 Apr 18 UT, imaged by Abel Cian (AEA). North is towards the top.
Abel’s color mage (Fig 11) is the first look we have at the normal appearance of what the crater should have looked like to Schroter, back in 1787. Unfortunately, the Cameron catalog does not say what the LTP actually was, so one can only speculate – maybe it was the lack of the SW ray? If anyone has ac- cess to historic records and knows something more about the 1787 Oct 07 event, please let me know. For now, I will leave the weight at 1.
Earthshine: On 2020 Apr 24 UT 19:00 Leonardo Mazzei (UAI) and at 19:07 Luigi Zanatta (UAI) imaged the Moon to see if they could detect the following Lunar Schedule phenomena:
BAA Request: Please try to image the Moon as a very thin crescent, trying to detect Earthshine. A good telephoto lens will do on a DSLR, or a camera on a small scope. We are attempting to monitor the brightness of the edge of the earthshine limb in order to follow up a project suggested by Dr Martin Hoff- mann at the 2017 EPSC Conference in Riga, Latvia. This is quite a challenging project due to the sky brightness and the low altitude of the Moon. Please do not attempt if the Sun is still above the horizon. Do not bother observing if the sky conditions are hazy. Any images should be emailed to: a t c @ a b e r . a c . u k The Lunar Observer/June 2020/ 88
Figure 12. Earthshine on 2020 Apr 24. (Left) Image by Leonardo Mazzei (UAI) taken at 19:00. (Right) Image by Luigi Zanatta (UAI) taken at 19:07UT.
The effect we are looking for, which might indicate forward scattering of light by dust particles above the sunset limb, would be an illuminated arc around the earthlit limb. This is clearly not visible in the images (Fig 12), so we will keep on looking, trying even smaller lunar phases.
General Information: For repeat illumination (and a few repeat libration) observations for the coming month - these can be found on the following web site: http://users.aber.ac.uk/atc/ lunar_schedule.htm . By re-observing and submitting your observations, only this way can we fully resolve past observational puzzles. To keep yourself busy on cloudy nights, why not try “Spot the Difference” be- tween spacecraft imagery taken on different dates? This can be found on: http://users.aber.ac.uk/atc/tlp/ spot_the_difference.htm . If in the unlikely event you do ever see a LTP, firstly read the LTP checklist on http://users.aber.ac.uk/atc/alpo/ltp.htm , and if this does not explain what you are seeing, please give me a call on my cell phone: +44 (0)798 505 5681 and I will alert other observers. Note when telephoning from outside the UK you must not use the (0). When phoning from within the UK please do not use the +44! Twitter LTP alerts can be accessed on https://twitter.com/lunarnaut .
Dr Anthony Cook, Department of Physics, Aberystwyth University, Penglais, Aberystwyth, Ceredigion, SY23 3BZ, WALES, UNITED KINGDOM. Email: atc @ aber.ac.uk
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Key to Images In This Issue
1. Alphonsus 21. Julius Caesar 41. Petavius 2. Alpine Valley 22. Kepler 42. Picard 3. Aristarchus 23. Lacus Excellentiae 43. Plato 44. Posidonius 4. Aristoteles 24. Lamont 5. Atlas 45. Ramsden 25. Langrenus 46. Ross 6. Barrow 26. Licetus 47. Schickard 7. Bayer 27. Maginus 48. Schiller 8. Bessel 28. Mare Australe 49. Serpentine Ridge 9. Cassini 29. Mare Fecunditatis 50. Sinus Iridum 10. Clavius 30. Mare Smythii 51. Tarunitus 11. Copernicus 31. Mare Vaporum 52. Thebit 12. Daniell 32. Marius 53. Theophilus 54. Torricelli 13. Euclides 33. Maurolycus 14. Gassendi 55. Tycho 34. Menelaus 56. Von Braun 15. Gemma Frisius 35. Messier 16. Gutenberg 36. Mons La Hire 17. Hadley Rille 37. Montes Apenninus 18. Hainzel 38. Moretus 19. Herschel 39. Mutus 20. Hyginus 40. Norman
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