July OBSERVER(220Dpi)

Home , 136 Tauri, 14 Ceti, 90 Tauri, Epsilon Tauri, Phi Aquarii, Zeta Tauri

THE OBSERVER OF THE TWIN CITY AMATEUR ASTRONOMERS

Volume 45, Number 7 July 2020

INSIDE THIS ISSUE:

1«Editor’s Choice: Image of the Month – Messier 27 2«President’s Note 2«NCRAL’s Season Messier Mini Marathons 3«Calendar of Astronomical Events – July 2020 3«New & Renewing Members/Dues Blues/E-Mail List 4«This Month’s Phases of the Moon 4«This Month’s Solar Phenomena 4«AstroBits – News from Around the TCAA 6«Waynesville Observatory Use Policy Statement 7«CDK 24” Telescope Coming Online at WO 7«Celestron NexStar 11” Telescope Donated to TCAA 8«TCAA Image Gallery 9«Maintenance Work at Waynesville Observatory 10«Did You Know? 11«TCAA Active on Facebook 11«July 2020 with Jeffrey L. Hunt 23«Renewing Your TCAA Membership 23«Online Public Talks for 2020 24«TCAA Treasurer’s Report as of June 26, 2020

The TCAA is an affiliate of the Astronomical League as well as its North Central Region. For more information about the TCAA, be certain to visit the TCAA website at http://www.tcaa.us/

Visit http://www.astroleague.org for additional information about the

Astronomical League and its EDITOR’S CHOICE: IMAGE OF THE MONTH – MESSIER 27 numerous membership benefits, including observing programs. This image of M27 (Dumbbell Nebula) was taken by Scott and Emily Wade and Deva Chatrathi. Scott writes, “Here’s an image of M27 Also, visit the NCRAL website at that was captured on the evenings of 6/23 (Emily & Scott) and 6/25 http://ncral.wordpress.com for in- (Deva & Scott) using the CDK 17” telescope with the QHY600 formation about our North Central camera and RGB filters. We captured thirty-five 300-second Region. Find out about the many exposures (12R, 11G, and 12B) at -20° Celsius with binning set to 2. benefits of your membership from The image was processed by Emily and Scott using PixInsight and this site. Photoshop.

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

PRESIDENT’S NOTE The OBSERVER June was as beautiful an astronomy is the monthly electronic newsletter of Twin month as the months prior were dismal. City Amateur Astronomers, Inc., a registered 501(c)(3) non-profit educational organiz- Personally, I was able to engage in my ation of amateur astronomers interested in passion for astrophotography on nine studying astronomy and sharing their hobby nights of the month, more nights than I with the public. accumulated since November of last

year. It was a joy to see such crystal-clear TCAA OFFICERS & CHAIRPERSONS moonless nights. I even took the

President, Director, & Property Manager opportunity to complete the NCRAL Tim Stone 309-531-2401 Summer Mini Messier Marathon. [email protected] Even though I have my

Vice President & Director/Membership Coord. Astronomical League Messier Certifi- Tom Willmitch 309-846-2423 cate, it was fun to revisit objects I President Tim Stone [email protected] probably haven’t seen since I completed

Treasurer & Director/Registered Agent that observing program. When was the last time I visited diminutive M80? What Dave Osenga 309-287-0789 object did I even view for my observation of enigmatic M102? This time, at least, I [email protected] viewed NGC 5907, The Silver Sliver, even though I doubt very much Messier could Assistant Property Manager/ALCor have possibly seen it. In fact, I’ve photographed it several times, but I’ve never seen Scott Wade 309-310-2464 it in an eyepiece. I hope to complete the Autumn, Winter, and Spring programs as [email protected] well. Hopefully I won’t have to freeze to death for the Winter one! 5th Director The point I’m trying to make here is: the weather is warm, clear nights have Sunil Chebolu 678-896-5967 returned, your goto mount is permissible (that’s what I did), and the program is laid [email protected] out for you. There’s NO reason not to dust that telescope off and do the program! Secretary/Historian/Editor Come on out to one of the observatories. If you don’t want to mess with a telescope, Carl J. Wenning 309-830-4085 then use the club scope in the SGO dome. I completed my observations in less than [email protected] an hour. We are astronomers. Let’s do some astronomy! Technology Coordinator/Assistant Editor Tim Stone Sandullah Epsicokhan 309-828-0227 [email protected]

Webmaster NCRAL SEASONAL MESSIER MINI MARATHONS

Lee Green 309-454-7349 [email protected] Editor’s Note: The following notice about NCRAL Seasonal Messier Mini Marathons

AL Observing Club Coordinator was taken from the Northern Lights newsletter: Lisa Wentzel unlisted number [email protected] Don’t overlook the NCRAL Seasonal Messier Marathons! The Seasonal Messier Marathon observing programs are NCRAL’s introduction to viewing the Messier The OBSERVER objects. This program is intended to serve as motivation to get NCRAL-affiliated Carl J. Wenning, Editor members out under the stars to observe. Submission deadline two days before The program permits the use of goto telescopes to find the objects and, as such, the end of each month. the program must not be seen as proof of observing prowess. NCRAL will permit Astronomical League’s Messier observing program to serve that purpose. MEMBERSHIP DUES Up-to-date details about the Region’s four seasonal observing programs and Individual Adult/Family $40 helpful observing record sheets can now be found on the NCRAL website: Full-time Student/Senior $25 https://ncral.wordpress.com/awards/. (Senior status equals ages 60+) Summer Objects: M83, M102, M5, M13, M92, M9, M10, M12, M14, M19, M62, To join, send your name, contact info, and M107, M4, M6, M7, M80, M16, M8, M17, M18, M20, M21, M22, M23, M24, M25, dues payment to Dave Osenga, TCAA M28, and M54. (28 objects). Note per the NCRAL observing program chair that M51 Treasurer, 1109 N. Linden St., Normal, IL will be accepted in lieu M83 that disappears very early during the summer months. 61761-1471.

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

CALENDAR OF ASTRONOMICAL EVENTS – JULY 2020 NEW & RENEWING MEMBERS

MORNING PLANETS (7/15): Mercury (☿), Venus (♀), Mars (♂), The following individuals have paid dues for new or renewed memberships as of June 26, 2020. (Others who Saturn (♄), Uranus (⛢), and Neptune (♆) paid after that date will appear in the August 2020 issue EVENING PLANETS (7/15): Jupiter (♃) of The OBSERVER.)

The following table gives the date and time (24-hour clock) of Welcome! Welcome! Welcome! Welcome! Welcome! important astronomical events for this month. All events are given in Central Daylight Time. New: James Wolf

Renewing: Mark Boulware, Sunil Chebolu Day Time Event Welcome! Welcome! Welcome! Welcome! Welcome!

03 22:18 Moon at Descending Node 04 08 Earth at Aphelion: 1.01669 AU DUES BLUES

04 23:30 Pen. Lunar Eclipse; mag=0.355 If you have received a dues statement email along 04 23:44 FULL MOON with this issue of The OBSERVER, please send your dues 05 16:37 Jupiter 1.9°N of Moon to Mr. Dave Osenga, TCAA Treasurer, 1109 N. Linden St., 06 03:45 Saturn 2.5°N of Moon Normal, IL 61761-1471. Dues are currently $25 for seniors 10 07 Venus at Aphelion (60 years of age and over) and $40 regular.

11 07:10 Venus 1.0°N of Aldebaran 11 14:36 Mars 2.0°N of Moon SUBSCRIBING TO THE TCAA EMAIL LIST

12 14:27 Moon at Apogee: 404201 km Welcome to the [email protected] group at Groups.io. 12 18:29 LAST QUARTER MOON This is a free, easy-to-use group email service set up for 14 02 Jupiter at Opposition the TCAA’s communication purposes. You can subscribe, visit your group, read and post messages here: 16 20:21 Aldebaran 3.8°S of Moon https://groups.io/g/tcaa 17 02:26 Venus 3.1°S of Moon The email address for this group is [email protected]. 18 07:33 Moon at Ascending Node After you successfully subscribe, please add this email 18 22:54 Mercury 3.9°S of Moon address to your safe sender list in your email client’s 20 12:33 NEW MOON contacts, so emails from this list are not classified as junk 20 17 Saturn at Opposition mail. Once subscribed, you can set your subscription 22 10 Mercury at Greatest Elong: 20.1°W settings here: https://groups.io/g/tcaa/editsub. You can 22 15:50 Regulus 4.3°S of Moon opt to receive all messages in individual emails, collections 24 23:54 Moon at Perigee: 368367 km of messages in a digest, a daily summary, or only special 27 07:32 FIRST QUARTER MOON notices. If you do not wish to belong to this group, you 27 16 Delta-Aquarid Meteor Shower may unsubscribe by sending an email to 31 04:32 Moon at Descending Node [email protected] If you have general questions about the group, email This Calendar of Astronomical Events courtesy of Fred Espenak. [email protected]. For questions not answered there, http://www.astropixels.com/ephemeris/astrocal/astrocal2020cst.html contact the moderators of this group (Deva C., Tim S., and Carl W.) by emailing [email protected].

EVENING SKY MAP Get the current evening sky map along with a more detailed celestial events calendar at the following URL: http://www.skymaps.com/

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

THIS MONTH’S PHASES OF THE MOON

Full Moon Last Quarter New Moon First Quarter Saturday, July 4 Sunday, July 12 Monday, July 20 Monday, July 27

All moon phase dates are Central Standard Time. Moon phases for the 2020 calendar year can be found by clicking here. Images provided by J. K. Howell of the Champaign-Urbana Astronomical Society & used with permission.

THIS MONTH’S SOLAR PHENOMENA

In the table below, you will find times of sunrise and sunset along with rising and setting azimuths (Az), length of the day including the change from the previous day, start and end times of astronomical twilight, and the time of solar noon along with the elevation (El) of the midday sun. These data come from https://www.timeanddate.com/sun/usa/bloomington

2020 Sunrise/Sunset Day Length Astronomical Twilight Solar Noon Solar Dist.

July Sunrise (Az) Sunset (Az) Length Diff. Start End Time (El) MIL. MILES 1 5:29 AM (58°) 8:30 PM (302°) 15:03:30 –0:36 3:25 AM 10:34 PM 12:59 PM (72.6°) 94.506 11 5:35 AM (60°) 8:26 PM (300°) 14:51:09 –1:10 3:35 AM 10:27 PM 1:01 PM (71.5°) 94.499 21 5:43 AM (62°) 8:20 PM (298°) 14:36:48 –1:38 3:48 AM 10:15 PM 1:02 PM (69.8°) 94.450

ASTROBITS – NEWS FROM AROUND THE TCAA ó On May 27th, TCAA member Roy Lawry (Lincoln, IL) ó Lisa Wentzel informs us that the American Association of contacted Secretary Carl Wenning about the possible Variable Star Observers (AAVSO) is offering its CHOICE donation of an 11” Celestron NexStar telescope. The Courses for free for the remainder of 2020. She notes, forerunner of the current CPC series, this particular “You do not need to be a member of the AAVSO to take a NexStar telescope was used only a few times by its owner course. These courses include online discussions, over the past 20-25 years and literally is in like new homework, and a final exam or project. I have found them condition. It has both GPS and “goto” capacity. Treasurer to be worthwhile. Registration is limited, so hurry!” Visit Dave Osenga has such a telescope and he is happy with his https://www.aavso.org/choice-schedule-registration- unit. After the offer was made known to the Board of 2020-members Directors, the Board voted unanimously to accept the ó Work continues on the polar alignment of the 24” donation on June 1st. If the telescope works as expected, telescope now that the northern side of the clamshell it likely will be moved out Waynesville Observatory for use dome can be retracted. There is a design flaw in the dome by members under the much darker sky found there. If the to the extent that when opened, the door to the north is telescope gets adequate use, there is an offer on the table partially blocked making its use inconvenient. The dome to purchase a small dome within which to house and use has been modified to allow for separate operation of the it. Stay tuned for details. north and south halves so that the doorway remains ó Sunil Chebolu has sent a link to his paper dealing with entirely unobstructed when the dome is open. The the packing Moons inside the Earth that was recently accompanying image shows the current situation with the published in Math Horizons. You may find Sunil’s paper at dome during a recent alignment on the evening of June 2nd. the following URL: https://arxiv.org/pdf/2006.00603.pdf

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

spectrum. The difference between the two is remarkable. See the first image below. The top is without the filter, bottom is with. Note the Ca triplet lines so clearly visible in the filtered version, but almost unidentifiable in the clutter of the unfiltered one.

With this filter in hand, I proceeded to acquire NIR data for the solar spectrum out to just past 10,000 Ångstroms. Of course, it has a lot of H2O clutter, but it also has significant solar features.

ó On the evening of June 7th, Carl Wenning observed the passage of bright white and green bolide to the south- southeast of Dayton, Ohio. From the triangulation of 120 observations, it appears that the meteor was approaching Cincinnati from the southeast. Carl estimated a magnitude of -3 and a duration of about 2 seconds (having seen only part of the passage). In the final moment the fireball

fragmented showing a splash of mostly green colors. The ó On June 4th the club leadership had its first look at the new tail was about 1° in length. The head was perhaps 10’ in TCAA website being developed by Deva Chatrathi and his width. You can view several videos of the meteor here: two friends. The leaders were impressed by the progress http://shorturl.at/bKLTZ that has been made and duly noted the complexity of the ó On the evening of June 11th, Dave Peters noted, “Had my task that Deva and his friends have undertaken. It is hoped Orion 10-inch out tonight. Viewed Messiers 51, 106, 81, 82, that the second draft can be released to the general 104, as well as comet C/2017 T2 (PANSTARRS).” (Editor’s membership for comment sometime in July. In the note: The comet was shining at magnitude 8.4 among the meantime, a somewhat limited TCAA website continues to stars of the Big Dipper’s bowl.) On the same evening, operate at its usual web address. Jamey Jenkins reported, “Yes...the skies were terrific last ó On June 5th, Bob Finnigan reported that the roll-off-roof night. I too was out till 2 AM searching out several new observatory at WO had its roofing caulk removed by our variables and visiting a number of old acquaintances.” carpenter friend Robin. It turned out that the wrong type ó Kevin Cook, Lighting and Signal Technician from the Illinois of caulk had been used earlier and that it did not adhere Department of Transportation, contacted Carl Wenning well to aluminum. It was replaced with the proper caulking on June 12th with the following note, “Mark Seppelt gave the next day. Plans now call for the painting of the walls me your email and ask that I give you a heads up about and two telescope piers inside the observatory. some possible lighting changes at the Funks Grove Rest ó On the morning of June 6th, Marc Tiritilli captured some Area. We are discussing [replacing] the high-pressure extremely impressive video the recent launch of Starlink sodium (HPS) fixtures with an LED option. The [new lights] satellites. He and his daughter were out at 4:30AM and are pointed directly downward instead of the current HPS were able to capture the following shot: fixture that is aimed at a 30- to 45-degree angle. If you https://www.facebook.com/marc.tiritilli.5/videos/10221 have any questions please let me know.” Carl got back to 707962103984/ Sorry, you’ll need to have a Facebook him to express thanks and to make the TCAA’s concerns account to view this video. known. He then responded with a detailed explanation ó On June 6th, Tim Stone reported, “A few weeks ago I that was forwarded to the TCAA leadership. We are hoping acquired a detailed near infra-red (NIR) solar spectrum for a positive outcome. Be reminded that Mark Seppelt and was a bit mystified by the seemingly unidentifiable mentioned in the note is a strong advocate of reducing up lines there. It took me a bit, but I realized I was seeing light and glare along the state’s highways. He spoke to the second order lines. I ordered a “long-pass” filter, with a TCAA several years ago during a September Mini transmission cutoff below 685nm, and re-acquired the NIR

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

Conference. He was brought in by Lisa Wentzel was Wenning did so from SGO on June 25th while Scott Wade serving as the TCAA Lighting Coordinator. and Devanand Chatrathi imaged M27 from PSO. ó Remember, by virtue of your TCAA membership you are ó Have you watched Sunil Chebolu’s public viewing session also a member of the Astronomical League as a member talk for June? It is titled Navigating with Stars. If you have of its North Central Region. Have your read the Summer not yet seen it, you can view this interesting and 2020 issue of Northern Lights yet, the newsletter of the informative program at https://youtu.be/SBorm9K6HLQ North Central Region of the Astronomical League? If you ó The editor has noted twice in the past that there is plenty have not, you may download it at the following URL: of evidence of mountain lions passing through Central https://ncral.wordpress.com/newsletter-archive/ Have Illinois in search of mates. Now, at least one black bear is you read the 2019-2020 NCRAL Region Report that on the prowl and being monitored by the Illinois summarized the year’s events? If not, you my download it Department of Natural Resources. The only thing that from https://ncral.wordpress.com/reports/ seems to be missing is tigers. “Lions, and tigers, and bears, ó Lisa Wentzel has been going to town recently taking oh my!” Nighttime observers viewing from rural locations advantage of the clear, dark skies. On the evening of June might want to be mindful of this information. 21st, Lisa completed the 28 requisite observations of the ó Carl Wenning has again updated TCAA Guide #2 – TCAA NCRAL Summer Mini-Marathon from her observing site Membership & Benefits. Of primary note, Carl has added a just outside of El Paso, IL. She is the first member of NCRAL section about interpersonal communications and their to complete this summer observing program. Lisa noted, role in developing relationships. He notes that without “I just finished the Summer Messier Marathon! I used two communications, a member will not feel part of the club. telescopes. I did most of my observations on my 10” Dob, This Guide, as well as nine other TCAA Guides to Amateur but also used my 6” f/5 Newt to move around my yard to Astronomy, may be downloaded from the following URL: get targets that are normally behind trees and rooftops. I http://tcaa.us/TCAAGuides.aspx got M83 as a smudge at the beginning of astronomical ó Sharon MacDonald recently shared an incredible time- twilight and finished about two hours later when the lapse video that shows 10 years of the sun’s history in only Ptolemy Cluster finally popped out from behind the 6 minutes. You might want to watch it! Here’s the link: trees. Once again this program made for a fun evening.” https://www.livescience.com/solar-decade-time-lapse- Congratulations Lisa! video.html ó Tim Stone completed the requisite observations for his ó The next meeting of the TCAA Board of Directors will be NCRAL Summer Mini Marathon from WO on June 24th. Carl held at the Wenning residence on at 6:30 PM on July 14th.

WAYNESVILLE OBSERVATORY USE POLICY STATEMENT

The TCAA Board of Directors wishes to encourage the membership to utilize the Waynesville Observatory site. It has very open skies and is much darker than at Sugar Grove Nature Center. With outdoor electricity available, it’s great for setting up a powered telescope and working on those Astronomical League observing programs we all said we were going to finish this year. Waynesville Observatory is on a parcel of land leased from the landowner who maintains a residence and farming operations at the site. In deference to the landowner, the TCAA Board of Directors feels it is prudent that the TCAA Property Manager be aware of when members are planning to use the site. To that end:

It is the policy of the TCAA Board of Directors that notification of planned use of the Waynesville Observatory site be communicated to the Property Manager no more than 24 hours before and no later than sunset on the evening of the planned usage. If this notification has not been given, then the member is asked to refrain from using the site that evening. Notification also may be made by email, either to the TCAA groups.io mailing list, or to the Property Manager at [email protected]. This notification may also be made using text messaging to the Property Manager’s phone at (309) 531-2401. If texting, please include your name in the text to let the Property Manager know the identity of the sender. Members should not make voice calls to the Property Manager’s number. This policy may be amended from time to time. Implementation of this policy and any changes to it is subject to vote by the Board of Directors. (Approved May 22, 2020)

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

CDK 24” f/11 TELESCOPE COMING ONLINE AT WO

During the wee morning hours of June 24th Tim Stone wrote, “Justin went out to the WO with me this evening with the goal of getting the 8300 camera and the focuser/rotator on the network. That work went very smoothly, so I decided to get focus on the 8300 and see if we could get it to plate solve. That went very smoothly, so I decided to attempt a 50-point pointing model using the piggyback scope. That went very smoothly, with the pointing accuracy at 30” in elevation and 2.4’ in azimuth as a result of our polar alignment using the alignment scope and 3D-printed holder performed earlier in the month. I decided that was good enough to attempt a first light photograph, and so that’s what I did (right). Here is a link to the full-resolution version of the image: https://bit.ly/3fYLkN7 It is 10x60-second RGB, unguided, with only rough focus, no flats, and very old darks. The color balance is not quite right because I have Vj and Bj filters in the G and B slots, just to experiment with using them in RGB photography. (I don’t think it works too well.) This image serves to give us a good idea of the field of view relative to a very familiar object.” In a follow- up note Tim stated, “This result is extremely promising! I couldn’t be more pleased at this point.” As Tim further noted, “There’s a lot more work to do. The This image of Messier 27 (Dumbbell Nebula) was taken with image shows some frost, so the desiccant plug needs to be the new CDK 24” by Tim Stone at Waynesville Observatory. baked... The AO needs to be brought up... the Thermal Control System needs to be installed... some finishing touches on the cable management should be applied... automated focusing needs to be set up... the fields of view of the 6” piggyback and the 24” relative to each other need to be established... the position of the AO pickoff mirror needs to be established,... motion limits need to be set... I’m sure I’m missing something...” From a historical perspective, Bob Finnigan noted that the telescope has been long in coming. In a note to the editor he mentioned the following details. The purchase of the CDK 24” f/11 telescope and yoke mount were approved by the TCAA Board of Directors on November 30, 2016, at a cost of $95,000. The construction process took about a year, and the telescope and mount were paid off on March 28, 2017. During this time, a clamshell dome was installed at WO to receive the new telescope and mount. After receiving the telescope, its installation was delayed by cold weather. After installation during the summer and autumn of 2019, the first picture (of the moon) was taken with this telescope. The “first light” date was October 6, 2019. The yoke mount’s alignment was delayed by many months of continuously cloudy skies and cold. Not until June of this year was it possible to make significant progress toward alignment. On the might of June 23/24, the first serious image was taken of M27 showing the capability of the next system. The time from approval of concept to the first picture with an almost fully operational system was three years and seven months. It is expected that the telescope will be fully operational in weeks.

CELESTRON NEXSTAR 11” TELESCOPE DONATED TO TCAA

On May 28th, TCAA member Roy Lawry of Lincoln, IL, made Carl Wenning aware of a possible telescope donation to the TCAA. Roy’s neighbor had purchased a Celestron NexStar 11” for his father perhaps 20 years earlier, but the father reportedly never used it more than twice. For the past two decades, the telescope rested covered in the garage of Roy’s neighbor. His neighbor, Jim Xamis, wanted to give the telescope away to a worthy cause and so contacted Roy who he knew is a TCAAer. Following a brief discussion of the offer and vote, the TCAA Board of Directors approved the donation of the telescope on June 1st. On June 17th, Carolyn & Carl Wenning traveled to Lincoln, Illinois, to pick up the donation. Included were the telescope were a 40mm Plössl eyepiece, tripod, instruction manual, and the book The NexStar User’s Guide by Michael Swanson. Because the telescope did not come with a power adapter or dew shield, Carl has donated a used Celestron PowerTank with cable and an unused dew shield from the CPC 11” that he had donated to the TCAA earlier. Testing of the telescope awaits. A suitable acknowledgement letter has been sent to Mr. Xamis.

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

TCAA IMAGE GALLERY

M108 BY SCOTT WADE – Taken with the 17-inch at PSO using M97 BY SCOTT WADE – This image of M97 – the Owl Nebula – the new QHY600 camera on June 12, 2020. Image consists of was taken on three nights: 5/22, 5/30, and 6/4. The image twenty-one 300-second exposures, 7 subs each of RBG. consists of 15 subs each of Hα, OIII, and SII.

NGC 5705/7/8 BY TIM STONE – Tim reported on June 15th, “After a stretch of terrible weather/clear-skies-with-bright-moon going back to late February, we FINALLY get some clear, dark moon nights. And spectacular nights at that. Excellent seeing and transparency, very dry air... wow, it’s like Earth is trying to make it all up to us. Here’s a shot of NGC 5705/7/8 [in Draco] with finder chart. The image was taken with the 16” at Waynesville Observatory. It consists of 14x600-second RGB for a total of 7 hours.” Note in the image to the right that the identifiers for NGC 5906 (a knot in 5907) and 5907 overlap one another.

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

M13 AND M57 BY JAMEY JENKINS – Jamey noted on June 15th, “Last week, after an evening of data collection for photometry of a class of variable stars called LPVs (Long Period Variable), I slewed the telescope over to a couple nearby classic deep sky objects for what amounts to literally, a quick ‘snapshot’. Some hobbyists spend hours photographing and creating absolutely beautiful portraits of star clusters, galaxies, and other distant ‘faint fuzzies,’ I spent a few minutes just for the fun of it collecting photons from the so-called Ring Nebula in the constellation Lyra and the globular star cluster Messier 13 in the constellation Hercules. Exposures? Ring Nebula 300 seconds, M13 60 seconds. For tech-geeks (see the image right), the telescope is a William Optics 102mm f/7 ED refractor, the camera an Atik 314L+ mono, and filter an Astrodon V Photometric. Image calibration was done in AstroImageJ and processing with Adobe Photoshop.”

1ST QUARTER MOON BY SUNIL CHEBOLU – Sunil remarked, “Last night [May 30] the Moon was at first quarter phase and it was very clear from Normal, IL. I got some very nice views and pictures through my binoculars (Canon image stabilization) and telescope (Celestron 130mm SLT). I played with several eyepieces (5mm, 9mm, and 25mm) and Barlow. The one attached here was taken with a 5mm eyepiece and a 13% neutral density filter. Lots of craters are clearly visible, especially the ones along the terminator. You really see the scars of time!”

Editor’s note. Sunil’s lunar image has been rotated 90° counterclockwise in order to fit into the limited space of this section’s layout.

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

ENDEAVOR AND ISS BY TIM STONE. On the evening of May 30th, Tim captured a show of Crew Dragon leading the International Space Station across the sky. Endeavor was on its way to a rendezvous with the ISS the following day. Tim remarked, “I observed the ISS and Endeavor this evening. The ISS was leading with Endeavor following by maybe 20 degrees. It became visible near Capella and entered the shadow near Vega. What an awesome sight!” Those who want to track Earth- orbiting satellites may do so by going online to the Heavens Above web site at: https://www.heavens-above.com/ Be certain to enter you location before starting.

MAINTENANCE WORK AT WAYNESVILLE OBSERVATORY

The last two weeks of June saw considerable maintenance work at Waynesville Observatory. The ground surrounding the roll- off-roof observatory had been banked too high and so there had been some water seepage during rain. The existing gravel was removed, and several inches of soil removed before the gravel could be replaced. The interior of the roll-off was painted black as well as the pier extensions at the bottom of the 16” and 10” telescopes. Lastly, old caulking on the roof of the roll-off and at the bases of the two domes housing the 20” and 24” telescopes had to be removed and replaced with better caulking agent. The ground surrounding the observing room (not shown) also will need to be regraded at a future time. The cost of all this work (3 laborers) was born by an anonymous donor for whom we give thanks! The photographs above were taken on 6/26/20.

DID YOU KNOW?

Are you looking for back issues of The Are you looking for information about Are you looking for the TCAA Guides to OBSERVER? Look no further than here: the history of the TCAA? Find out more amateur astronomy? Visit this page: http://tcaa.us/Observer.aspx here: http://tcaa.us/History.aspx http://tcaa.us/TCAAGuides.aspx

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

TCAA ACTIVE ON FACEBOOK

Did you know that the TCAA is very active on Facebook? We currently have nearly 900 followers, and very few of them are TCAA members! We encourage all users of social media to follow the TCAA to see what the club is doing and to learn about nightly events that only require the observer to step outdoors and view with the unaided eye. You can find us on Facebook by searching either TCAA or Twin City Amateur Astronomers. If you haven’t followed TCAA’s Face-book page recently, you have missed out on a lot of opportunities to view the sky with the unaided eye from town and country.

JULY 2020: MORNING’S CLASSIC 9 PLANETS WITH OUTER PLANETS IN OPPOSITION ~ by Jeffrey L. Hunt ~

The ecliptic is not so easy to follow in this part of the sky, without first magnitude stars to mark the sun’s route. Mars is in the east-southeast, about one-third of the way up in the sky. Among this dim starry background, Fomalhaut is low in the south-southeast. To the east, the Great Square of Pegasus is about midway up in the sky. The stars of Andromeda begin at the Square’s northern corner and point toward Perseus. Autumn’s flagship deep sky object, the Great Andromeda Spiral, is over midway up in the east. At the end of evening twilight, the gibbous moon is at the meridian, near the Celestial Scorpion that is poised to defend its southern high point. The ecliptic’s bright markers – Spica and Regulus – are in the western sky. Spica is low in the southwest, beneath Arcturus, and Regulus - with the Sickle of Leo – is near the western horizon. At this hour, the Summer Triangle is spread across the sky, midway up in the east. Sagittarius is east of the meridian. The Teapot parallels the horizon. It is followed by bright Jupiter and Saturn. In the north, the Big Dipper is high in the northwest, while Cassiopeia is low in the northeast, above the stars of Perseus that are rising. This chart shows the motion of Venus as it moves through During July 2020 observers can see the “Classic 9” planets Taurus during July. Make daily observations with a binocular to see its changing position compared to the starry in the morning as well as some dwarf planets if you have dark background. skies, enough aperture, and finder charts. This is described further in the section that outlines the night sky at mid- As the second half of the calendar month. year begins and morning twilight starts, This month, Jupiter reaches its opposition on July 14, the Summer Triangle – Vega, Deneb, followed by Saturn six days later. Mercury reaches its greatest and Altair – are high in the sky, west of morning elongation on July 22. the meridian. The faint glow of the As Jupiter is near opposition, it brightens slightly in the Milky Way emerges from the southwest sky and is closer to Earth. Attempt to locate its Great Red Spot horizon, washes through Cygnus, (GRS). The predictions in the daily notes are best attempts engulfs Deneb near the zenith, flows from known factors to predict when the GRS is along Jupiter’s downward through Cassiopeia and Perseus, and reaches the central meridian. Since the GRS wanders in longitude, horizon between Capella and the Pleiades. The outer planet attempt to observe this enormous atmospheric effect in the pair, Jupiter and Saturn, are low in the sky and west of the Jovian clouds near the predicted times. If it’s not at the central meridian in eastern Sagittarius. The Teapot is now tilted position at the predicted time, then it’s likely to be nearby. toward the southwest horizon. The Big Dipper is low in the For your planning, the times are displayed at the beginning of northwest with the bend of its handle leading us to Arcturus, each daily note when the feature is visible. Since darkness now low in the west-northwest. The Dipper’s Pointers reliably only lasts about five hours, opportunities to observe the spot aiming northward toward that pole star that barely moves. in a dark sky are narrow. Further the best observing occurs

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

around the midnight hours when Jupiter is near the meridian. upper right of Saturn. Overnight, the planets move farther Later in the month, Jupiter’s altitude is very low when the GRS west. is present for the times listed that occur near the beginning of • July 2: GRS: 2:43 a.m. CDT, 10:34 p.m. CDT. Venus rises two morning twilight. During a few dates, the spot is visible before hours before sunrise. One hour later, nearly 10° in altitude, sunrise, then again during that evening. brilliant Venus is 4.0° to the upper right of Aldebaran and 0.9° to the upper right of δ1 Tau. Brightening Mars is over 38° up in the southeast, 3.1° to the left of 29 Psc. Jupiter is 18.0° up in the southwest. Saturn is 6.1° to the upper left of Jupiter. Each clear morning observe these giant planets as they retrograde, farther west compared to the starry background than the previous day. Jupiter is 2.1° below 56 Sgr, while Saturn is 3.0° to the lower right of σ Cap. In the evening sky about one hour after sunset, the bright gibbous moon (11.8d, 95%) is nearly 23° up in the south-southeast, 7.2° to the upper left of Antares (α Sco, m = 1.0). As midnight approaches, the moon is higher in the southern sky. Jupiter is nearly 19° up in the southeast. Saturn is 6.1° to the lower left of bright Jupiter. • July 3: One hour before sunrise, Venus, over 10° up in the July 1: This chart shows the background stars near Jupiter east-northeast, is 3.7° to the upper right of α Tau and 0.6° and Saturn. The planets are displayed for July 8. Make daily to the upper right of δ1 Tau. Bright Jupiter is over 17° up in observations with a binocular to see the planets retrograde the southwest. Saturn is 6.1° to the upper left of Jupiter. In compared to the reference stars. the starfield, Jupiter is 2.2° below 56 Sgr, while Saturn is 3.1° to the lower right of σ Cap. Use a binocular to see the • July 1: Mercury is a few hours past its inferior conjunction. stars with the planets. Meanwhile, Mars is nearly 39° up in It begins to move into the morning sky. Four bright planets the southeast. It is 3.6° to the left of 29 Psc. A binocular is – Venus, Mars, Saturn, and Jupiter – dot the ecliptic during needed to see Mars against the stars as well. One hour after early morning twilight. They span over 132° of ecliptic sunset, the moon (12.8d, 99%) is over 15° up in the longitude. One hour before sunrise, Venus (−4.7), over 9° in southeast. Locate a clear eastern horizon to find Jupiter altitude in the east-northeast, is 4.2° to the upper right of about 4° up in the east-southeast. The moon is nearly Aldebaran (m = 0.8) and 1.1° to the upper right of Delta1 between Jupiter and Antares, although the lunar orb is Tauri (δ1 Tau, m =3.8). Use a binocular to watch Venus closer to the star. As midnight approaches the moon is move through the Hyades. Through a telescope, the planet farther south. Jupiter is over 19° up in the south-southeast is a morning crescent, 19% illuminated and 43” in diameter. with Saturn 6.2° to its lower left. Saturn has inched Farther westward, Mars (m = −0.5) is among the dim stars westward; it is now in eastern Sagittarius. of western Pisces. It is nearly 38° up in the southeast, 2.5° • to the left of 29 Piscium (29 Psc, m = 5.1). Use a binocular July 4: Look for the bright morning planets one hour before to see Mars against the much dimmer starfield. Through a sunrise. Nearly 11° in altitude in the east-northeast, Venus telescope, Mars is nearly 12” across. Continuing west along is 3.4° to the upper right of α Tau and 0.4° to the right of δ1 the ecliptic, Saturn (m = 0.2) is over 22° up in the south- Tau. Farther west along the ecliptic, Mars (m = −0.6) is 39.0° southwest, 6.0° to the upper left of Jupiter (m = −2.7). In the up in the southeast. It is in a dim starfield in Pisces. The Red starfield, Saturn is 2.0° to the lower right of Sigma Planet is 4.2° to the left of 29 Psc. Use a binocular to see the Capricorni (σ Cap, m = 5.2), while Jupiter is 2.1° to the lower quartet of bright morning planets among the stars. Bright right of 56 Sagittarii (56 Sgr, m = 4.8). As the planets Jupiter is in the southwest, nearly 17° above the horizon. continue to retrograde, watch the planetary pair move Saturn is 6.2° to the upper left of Jupiter. In the starfield, westward away from the reference stars. During these long Saturn is 3.2° to the lower right of σ Cap, while Jupiter is days that occur near the summer solstice, daylight and 2.3° below 56 Sgr. The bright moon is very low in the twilight last over 19.5 hours. One hour after sunset, the southwest, near the horizon. Our planet Earth is at Aphelion moon (10.8 days past the New phase, 88% illuminated) is at 6:35 a.m. CDT, 1.0167 Astronomical Units from our 2.6° to the upper right of Beta Scorpii (β Sco, m = 2.5). central star. In the evening, about two hours after sunset Saturn rises at about this time. An hour later (about 10:30 (10:30 p.m. CDT), the moon (13.9d, 100%) is about 15° up p.m.), Jupiter is over 11° up in the southeast and 6.1° to the in the southeast, over 10° to the upper right of Jupiter. Saturn, over 10° up in the southeast, is 6.2° to the lower left

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

of Jupiter. Use a binocular or block the moon’s glare to see that the bright moon is 1.4° to the upper left of Nunki (σ Sgr, m = 2.0), the star at the top of the handle of the Teapot of Sagittarius. The moon reaches its Full phase at 11:44 p.m. CDT.

The moon is 3.2° to the lower left of Saturn. The Jupiter – Saturn gap is 6.4°.

• July 6: One hour before sunrise, Venus, 12.0° up in the east- northeast, is 2.7° to the upper right of Aldebaran and 0.5° below δ1 Tau. The planet is inside the “V” of Taurus. Farther July 5: The planets are well-placed in the evening sky. Jupiter is 4.4° to the upper right of the bright moon while Saturn is westward along the ecliptic, Mars, over 40° in altitude in 4.2° to the upper left of the lunar orb. the southeast, is 3.1° to the lower right of 44 Psc. The bright moon (15.1d, 98%) is nearly 17° up in the south-southwest. • July 5: GRS: 12:12 a.m. CDT. Venus rises at Astronomical Saturn is 3.2° to the upper right of the moon, while Jupiter Twilight, when the sun is 18° below the horizon. It is 6.4° to the right of the moon. The two planets are 6.3° continues to rise before twilight begins until December 26, apart with Saturn to the upper left of Jupiter. Three hours 2020. One hour before sunrise, the four bright morning after sunset (about 11:30 p.m. CDT), the moon (15.9d, 95%) planets are spread across nearly 134° of ecliptic longitude. is 12° up in the southeast. Bright Jupiter is over 20° in Venus, nearly 12° up in the east-northeast is 3.1° to the altitude in the south-southeast, with Saturn 6.3° to its lower upper right of Aldebaran and 0.8° to the lower right of δ1 left. Saturn is over 11° to the upper right of the moon. Tau. Through a telescope, the brilliant planet is 23% • July 7: GRS: 1:50 a.m. CDT. One hour before sunrise, over illuminated and 41” in diameter. Mars, near the Pisces – 12° in altitude in the east-northeast, Venus is 2.3° to the Cetus border, is nearly 40° up in the southeast. It is 3.5° to upper right of Aldebaran, 0.8° to the lower left of δ1 Tau, the lower right of 44 Piscium (44 Psc, m = 5.8). With the and 0.6° to the lower left of Delta2 Tauri (δ2 Tau, m = 4.8). bright moon in the southwest, use a binocular to see the Continue to watch Venus move through the Hyades cluster starfield. That bright moon (14.1d, 100%) is nearly 10° up in with a binocular. Observe that Venus and the three stars the southwest, 3.1° to the upper left of Nunki and 8.1° to are nearly in a line that starts at α Tau and ends at δ1 Tau. the lower right of Jupiter. Saturn is 6.2° to the upper left of Farther west along the ecliptic, Mars is over 40° up in the bright Jupiter. The sun has the same celestial longitude southeast, and 2.9° to the lower right of 44 Psc. Farther today as Sirius (α CMa, m = −1.5), although the Dog Star is westward again, the moon (16.1d, 95%), in central over 39° south of the sun. The night’s brightest star rises Capricornus, is nearly 24° up in the south-southwest. into morning twilight during mid-August. In the evening, Farther west is Jupiter, 15.0° up in the southwest. Dimmer two hours after sunset (about 10:30 p.m.), the moon (14.9d, Saturn is 6.4° to the upper left of its brighter outer planet 99%) is nearly 10° up in the southeast. Jupiter is 4.4° to the companion. Two hours after sunset (about 10:30 p.m. CDT), upper right of the moon, while Saturn is 4.2° to the upper bright Jupiter is over 14° up in the southeast. Saturn is 6.4° left of the lunar orb. to Jupiter’s lower left. In the starfield, Jupiter is 2.7° to the lower right of 56 Sgr, while Saturn is 3.4° to the upper right

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

of σ Cap. Use a binocular to see the planets among the stars. 2.7.) Messier 4 (M4, NGC 6121) is a globular star cluster, Both planets continue to retrograde. 1.3° to the west of Antares. It can be seen without optical help in a dark sky. In apparent size, the cluster is half the diameter of the moon. In the Messier Album, author John Mallas writes, “This cluster is a well-defined circular glow with a brighter center. At 214x the outer pars of the globular are broken up into faint stars and the mid-portion appears partially resolved” (p. 41). M4 is about 7,200 light years away, between our solar system and the galactic center. Globular clusters revolve around the galaxy’s center in orbits that largely carry them out of the galactic plane. They are found across the sky, largely toward the Sagittarius region. How many globular clusters have you observed in the Winter Sky – near Orion? Two open star clusters (M6 and M7) are found near the Scorpion’s stinger. M6 (NGC 6405) is 5.0° to the upper left of λ Sco. In apparent size, the cluster is nearly the size of the moon. This is a great

July 8: Scorpius at the meridian. The Celestial Scorpion with binocular object with the reddish variable BM Scorpii (BM its bright star Antares, along with its classic pincers, guards Sco, m = 6.0) the obvious stellar marker in the cluster, while the southern horizon. most of the other stars in the cluster are blue or white. M7 (NGC 6475) is 3.7° to the lower left of M6 and 4.7° to the • July 8: Mars moves into Cetus. Mars moves across this upper left of λ Sco. It is in a bright section of the Milky Way. corner of Cetus in 19 days, then back into Pisces. The With a binocular compare the colors of stars with those in constellations are not uniform in shape and size. The M7. As the Scorpion crosses the meridian locate this ecliptic is less than 1° from a corner of Cetus near incredible constellation and three of the wonders of the coordinates Right Ascension, 0 hours, 26 minutes; Milky Way. As a side note, the chart of Scorpius that Declination, 2°. Cetus also bounds Aries to the south, but accompanies this daily note was produced using some “old Mars moves north of the ecliptic after its opposition and it school” practices. Before the current days of creating does not return to this constellation this apparition. Ninety screen shots from planetarium programs and annotating minutes before sunrise (about 4 a.m. CDT), it is 37° up in them, we calculated the altitudes and azimuths of celestial the southeast. Use a binocular to observe that the Red objects with programmable calculators, plotted the data on Planet is 0.7° to the lower right of 10 Ceti (10 Cet, m = 6.2). graph paper, transferred those positions to white paper, Watch Mars’ motion relative to the star during the next few and finished the piece with press-on letters. Depending on mornings. One hour before sunrise, brilliant Venus is over the number of objects, the process could take half a day. 13° in altitude in the east-northeast. It is 2.0° to the upper Recently, I found the chart in my files from the early 1980s right of Aldebaran and 0.9° below Delta3 Tauri (δ3 Tau, m = and decided to include it in this month’s article after 4.3). The planet is at the midpoint of its interval of greatest performing some digital cleanup from the aging of the brightness. The waning gibbous moon (17.1d, 89%) is nearly paper. 30° up in the south-southwest. Bright Jupiter is farther west, • July 9: GRS: 3:28 a.m. CDT, 11:19 p.m. CDT. One hour over 14° up in the southwest, 6.4° to the lower right of before sunrise, nearly 14° up in the east-northeast, Venus Saturn. Among the stars, Jupiter is 2.9° below 56 Sgr. Saturn is 1.6° to the upper right of Aldebaran and 1.2° to the lower is 3.4° to the lower right of σ Cap. In the evening sky, about left of δ3 Tau. Venus is on a line between the two stars. 2 hours after sunset, Jupiter is nearly 15° in altitude in the Mars is nearly 42° up in the southeast, 0.7° to the lower left southeast. Saturn is 6.5° to Jupiter’s lower left. Without the of 10 Cet. Use a binocular to see the star with Mars. The moon in the sky, the magnificence of the classic Scorpion, moon (18.1d, 82%), in southeastern Aquarius, is near three with its deep sky splendors, is at the meridian. Ruddy dimmer stars. Use a binocular to see Tau Aquarii (τ Aqr, m Antares is less than one-fourth of the way up in the sky. The = 4.0) 1.2° to the upper left and Delta Aquarii (δ Aqr, m = head is to the upper right of this bright star. The classic 3.2), 3.0° to the lower left of the gibbous moon. Notice that pincers, Zubenelgenubi and Zubeneschamali, are in the 69 Aquarii (69 Aqr, m = 5.6) is 0.7° to the left of the moon. south-southwest. The arachnid’s body curves down toward Bright Jupiter is farther west, less than 14° up in the the horizon, then the tail curls back to the stinger (Lambda southwest. Saturn is 6.5° to the upper left of the bright giant Scorpii – λ Sco, m = 1.6 – and Upsilon Scorpii – υ Sco, m = planet. The pair continues to retrograde. Watch them move

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

from morning to morning relative to the stars. This morning Cet. Farther eastward on the ecliptic, nearly 15° up in the Jupiter is 2.8° below 56 Sgr. Saturn is 3.5° to the lower right east-northeast, brilliant Venus is 1.0° to the upper left of of σ Cap. In the evening sky, about 2 hours after sunset Aldebaran. The planet is to the left of a line that connects (about 10:30 p.m. CDT), Jupiter is over 15° in altitude. Aldebaran and ε Tau. Across the sky, bright Jupiter is in the Saturn is 6.5° to Jupiter’s lower left. southwest, over 12° up. Saturn is 6.6° to the upper left of • July 10: The span from Venus to Jupiter is over 136° of Jupiter. In the starfield, Jupiter is 3.0° below 56 Sgr. Saturn ecliptic longitude. One hour before sunrise, Venus, over 14° is 3.6° to the lower right of σ Cap. In the evening, about two in altitude in the east-northeast, is 1.2° above α Tau. Also hours after sunset, Jupiter is over 16° in altitude in the note that the brilliant planet is to the right of a line that southeastern sky. Saturn is 6.6° to Jupiter’s lower left. connects Aldebaran and Epsilon Tauri (ε Tau, m = 3.5). • July 12: GRS: 12:57 a.m. CDT. This morning is the Venus – Venus is at its greatest illuminated extent. The illuminated Aldebaran conjunction, 89 days after their wide portion of the planet covers the largest area of the sky. In conjunction in the evening sky. One hour before sunrise, essence, it is at its brightest. For a technical explanation, see locate Venus about 15° up in the east. It is 0.9° to the upper https://tinyurl.com/venus-greatest-illuminated. Through a left of Aldebaran. Venus passes the star again (4.1°) on July telescope, observe that the morning crescent is 37” across 1, 2022, in the morning sky. (Venus is 5.7° from Aldebaran and 27% illuminated. Farther westward along the ecliptic, on May 16, 2021, but this occurs during bright twilight Mars (m = −0.7) is nearly 42° up in the southeast. The planet during the next evening apparition.) This morning, farther is 1.0° to the lower left of 10 Cet. With a binocular also note west along the ecliptic, the slightly gibbous moon (21.1d, that Mars is nearly between 10 Cet and 14 Ceti (14 Cet, m = 56%) is 40.0° up in the southeast. Mars is 6.2° to the upper 5.9). The moon (19.1d, 74%) is over 17° to the lower right right of the moon. With a binocular note that the Red Planet of Mars. Bright Jupiter is 13.0° up in the southwest. Dimmer is 0.5° above 14 Cet. Jupiter (m = −2.8) is low in the Saturn is 6.5° to the upper left of the Giant Planet. In the southwest, while Saturn (m = 0.1) is 6.6° to the Giant starfield, Jupiter is 2.9° below 56 Sgr, while Saturn is 3.6° to Planet’s upper left. Today the sun has the same celestial the lower right of σ Cap. In the evening, two hours after longitude as Castor (α Gem, m = 1.6). The star is 10° north sunset, Jupiter is nearly 16° in altitude in the southeast. of the ecliptic. The moon is at apogee at 2:27 p.m. CDT. It is Saturn is 6.6° to its lower left. 251,158 miles away. The moon reaches its Last Quarter phase at 6:29 p.m. CDT. Two hours after sunset, Jupiter is nearly 17° up in the southeast. Saturn is 6.7° to the lower left of Jupiter. In the starfield, Jupiter is 3.2° to the lower right of 56 Sgr. Saturn is 3.8° to the upper right of σ Cap. Both planets continue to retrograde. Mars rises before midnight CDT. • July 13: One hour before sunrise, Venus is nearly 16° up in the east, 1.2° to the left of Aldebaran. The moon (22.1d, 46%) is nearly 39° in altitude in the east-southeastern sky. Mars – over 40° up in the south-southeast – is over 17° to the upper right of the thick lunar crescent. Through a binocular observe that Mars is 0.8° to the upper left of dim 14 Cet. Note that Fomalhaut (α PsA, m = 1.2) is at the meridian at this hour, about 20° in altitude. Jupiter is about 11° up in the southwest. Saturn is 6.7° to Jupiter’s upper left. In the evening sky, about two hours after sunset (10:30 p.m. CDT) Jupiter is 17.0° up in the southeast. Saturn is 6.7° to the lower left of the Giant planet. In the starfield, Jupiter is 3.3° to the lower right of 56 Sgr. Saturn is 3.8° to the upper

July 11 & 12: The moon passes Mars in the southeastern sky right of σ Cap. before sunrise. • July 14: GRS: 2:43 a.m. CDT, 10:26 p.m. CDT. Jupiter (m = −0.8) is at opposition at 2:58 a.m. CDT. At this time the • July 11: One hour before sunrise, the bright moon (20.1d, Giant Planet is nearly 21° up in the south-southwest. Venus 65%) is nearly 40° up in the south-southeast. Mars is 6.1° to is at its farthest southern celestial latitude of this apparition, the upper left of the waning gibbous moon. With a −4.52°. Over 16° in altitude in the east at one hour before binocular note that Mars is 0.7° to the upper right of dim 14 sunrise, Venus is 1.6° to the lower left of Aldebaran. The

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

moon (23.1d, 36%), over 35° up in the east-southeast, is is 6.6° above the ecliptic. Pluto is at opposition at 2:12 p.m. nearly midway from Venus to Mars. The crescent is slightly CDT. Two hours after sunset, Jupiter, nearly 18° up in the higher than the Pleiades, about 25° to the left of the moon southeast, is 6.8° to the upper right of Saturn. In the and about 14° to the upper right of Venus. Mars is nearly starfield, Jupiter is 3.5° to the right of 56 Sgr. Saturn is 4.0° 45° up in the south-southeast, 1.3° to the upper left of 14 to the upper right of σ Cap. Just before midnight, Pluto (m Cet. Use a binocular to see Mars among the stars in this dim = 14.3) is nearly 24° up in the south-southeast, 1.7° to the starfield. Jupiter is 10.0° up in the southwest, 6.8° to the lower left of Jupiter. You’ll need some aperture and darker lower right of Saturn. This evening, Jupiter rises at sunset. skies to see this ninth “classic planet.” Two hours later, it is over 17° in altitude in the south- At morning twilight’s beginning at mid-month, four bright southeastern sky. Saturn is 6.8° to the lower left of the planets – Venus, Mars, Saturn, and Jupiter - span the morning Giant Planet. In the starfield use a binocular to see Jupiter sky. The crescent moon and the Pleiades are low in the east, 3.4° to the lower right of 56 Sgr, while Saturn is 3.9° to the above Venus. Capella has nearly the same altitude as the lower right of σ Cap. Jupiter is in the sky all night, and its Pleiades as it gleams from the northeast. Farther westward, sets near sunrise tomorrow morning. Mars, among the dim stars of Cetus, appears about midway from Fomalhaut in the south to Hamal (Aries) that is nearly halfway up in the east. The Great Square of Pegasus, high in the southeast and east of the meridian, subtly occupies that space. Andromeda and its Great Galaxy are high in the east. The string of Andromeda’s stars points at Perseus. The Summer Triangle – Vega, Deneb, and Altair – is now west of the meridian, high in the sky. Jupiter and Saturn are in eastern Sagittarius. Capricornus, resembling an inverted and stretched Star Trek patch, is to the left of the two outer planet pair and west of the meridian. The Milky Way arches across the sky, from the southwest horizon, through Cygnus, nearly overhead, through Cassiopeia and Perseus, and hits the horizon near Capella in the northeast. At the end of evening twilight, the meridian cuts through the tail of the Celestial Scorpion. Antares and its classic pincers – Zubenelgenubi and Zubeneschamali – are west of the celestial divider. Spica is low in the south-southwest with Arcturus high above it. The Big Dipper and its curving handle are about halfway up in the northwest. Regulus has set, but part of the Sickle of Leo

July 15: Bright evening planets Jupiter and Saturn are in the remains along with the Celestial Lion’s haunches. Looking southeast after the end of evening twilight. Jupiter is 6.8° to back toward the south, Sagittarius – with its famous teapot the upper right of Saturn. asterism – is east of the Scorpion’s stinger. Bright Jupiter and Saturn are in eastern Sagittarius, to the left of the Teapot. The • July 15: At 1 a.m. CDT, Mars is 11° up in the east, 77° to the Summer Triangle and its celestial sprawl of brighter east of Jupiter, now 26° up in the south. One hour before constellations dominate the sky, high in the east. The Milky sunrise, locate Venus nearly 17° up in the east, 2.1° to the Way’s light arches from the southern horizon past Altair, lower left of Aldebaran. The Venus – Jupiter gap is nearly through Cygnus and Cassiopeia, and into the horizon several 140° of ecliptic longitude. Through a telescope, Venus is a degrees east of the north cardinal marker. morning crescent that is 31% illuminated and 34.3” across. The Classic 9 planets (Mercury – Pluto), the moon, and The moon (24.1d, 28%) is over 30° up in the east, over 20° two dwarf planets are in the sky simultaneously on July 19 as to the upper right of Venus and nearly 13° to the right of Mercury approaches its greatest morning elongation and the the Pleiades. At this time, Mars is nearly 45° in altitude in moon wanes toward its solar conjunction. Here’s how to see the south-southeastern sky. Through a telescope, it is 12.8” this solar system gallery of planetary objects: across. Jupiter, now past opposition, is less than 10° up in - Because, Pluto, and Eris are quite dim and need the southwest. Saturn is 6.8° to the upper left of the Giant considerable aperture, start with Pluto when it crosses the Planet. When daytime and twilight are combined, the sky is meridian at about 1 a.m. CDT. Sky & Telescope magazine illuminated to some extent for over 19 hours. Pollux (β Gem, has a finder chart for Pluto (m = 14.3) in its July 2020 issue. m = 1.2) has the same ecliptic longitude as the sun. The star

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

Pluto is 1.6° to the lower left of Jupiter. Jupiter crosses the In addition to the photos that appear on TCAA’s web site meridian about seven minutes before Pluto; so, there is a and monthly newsletter, and those posted on TCAA’s bright marker to get you to Pluto’s vicinity. My back of the Facebook and Twitter accounts, I follow a Twitter account envelope calculations predict you’ll need at least a 10-inch (@peachastro) that publishes many photos of solar system telescope to see Pluto. The Sky & Telescope article reports objects. Recently several great photos of Mars have been at least an 8-inch aperture is needed. The steps in my displayed as well as photos of Jupiter and Saturn. The author calculation are at the end of this article. is Damian Peach (http://www.damianpeach.com/), an - Saturn is 6.8° to the upper left of Jupiter. That makes 3 astrophotographer from the United Kingdom. His web site planets! has many photos and courses on the subject. The Twitter account has some fine photos of what can be seen on Mars After locating Pluto, look for the dimmer planets before through a telescope. morning twilight begins at approximately 3:30 a.m. CDT. • July 16: GRS: 4:13 a.m. CDT, after the beginning of morning - Ceres (1Ceres, m = 7.5) is among a dim starfield in Aquarius twilight. One hour before sunrise, Venus, over 17° in with other 7th and 8th magnitude stars, 2.6° to the upper left altitude in the east, is 2.6° to the lower left of Aldebaran. of 88 Aquarii (88 Aqr, m = 3.6). The moon (25.2d, 19%), 9.9° to the upper right of Venus, is - Neptune (m = 7.8) is over 24° up in the east-southeast, 3.6° 7.4° to the lower right of the Pleiades. Farther westward to the left of Phi Aquarii (φ Aqr, m = 3.6). Another dim star along the ecliptic, Mars is nearly 45° in altitude in the south- 96 Aquarii (96 Aqr, m = 5.5) is 1.8° to the right of the planet. southeast. Still in Cetus, the Red Planet is 3.1° to the upper - As the beginning of morning twilight approaches, Uranus right of dim 20 Ceti (20 Cet, m = 4.8). Use a binocular to (m = 5.8), over 26° up in the east, is 0.8° to the right of 29 track Mars through this dim stellar section of the ecliptic. Arietis (m = 6.0). Increase the magnification to see the disk Bright Jupiter is less than 9° up in the southwest with Saturn of the planet. On the morning of July 14, the moon is 4.8° 6.9° to its upper left. Two hours after sunset, Jupiter is over to the lower right of the planet. 18° up in the southeast, 6.9° to the upper right of Saturn. In - Maybe knowing that Eris (136188Eris, m = 18.6) is there is the starfield, Jupiter is 3.6° to the lower right of 56 Sgr and enough, because you’ll need at least a 1.9-meter telescope 1.7° to the lower left of 50 Sagittarii (50 Sgr, m = 5.6). Saturn to see it. Eris is 25.0° up in the east-southeast, 4.3° to the is 3.6° to the upper right of σ Cap. upper right of 60 Ceti (60 Cet, m = 5.4) - Mars is 35° up in the southeast. - Venus is appearing low in the east-northeast, near Aldebaran. - Depending on the morning of these observations, Mercury becomes visible. On July 19, the moon is near this speedy planet. For the next several mornings, the Classic 9 planets are in the sky. Jupiter is quickly disappearing as Mercury passes its greatest elongation.

As Mars becomes brighter and closer to us, here are some sources for planning your Mars observing:

• For the latest news in observable Martian features and observing conditions, visit the Association of Lunar and Planetary Observers (ALPO) website at http://www.alpo- astronomy.org/marsblog/. • Another source from ALPO describes large-scale events of the planet’s apparition can be found at http://www.alpo- astronomy.org/marsblog/wp- content/uploads/2020/02/CalendarOfEventsCORRECTED.p

df July 17: Look for a spectacular grouping of the crescent • From Sky & Telescope: To determine what is visible on the moon, Venus, and Aldebaran before sunrise. Martian surface on any date and time, go to https://is.gd/marsprofiler. • July 17: GRS: 12:04 a.m. CDT. This morning’s grouping of the crescent moon and Venus is the second closest of this Venusian apparition. Including Aldebaran and the Pleiades,

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

their low altitude in the sky should capture the imagination lower right of 56 Sgr and 1.6° to the lower left of 50 Sgr. of photographers and artists with the celestial spectacular Saturn is 4.1° to the upper right of σ Cap. Use a binocular to in perspective with terrestrial features. One hour before see the planets against the starry background. The giant sunrise, Venus is over 17° up in the east. The crescent moon planet pair continues to retrograde. (26.2d, 12%) is 3.2° to the left of Venus, while Aldebaran is • July 18: One hour before sunrise, Venus is nearly 18° up in 3.2° to the upper right of the brilliant planet. While the the east. Find Aldebaran, 3.8° to the upper right of the moon is 12% illuminated, Venus is 32% illuminated through brilliant planet. The crescent moon (27.2d, 6%) is over 10° a telescope, a morning crescent. This morning marks the up in the east-northeast, nearly 15° from Venus. Farther end of the interval of Venus’ greatest brightness. Farther west on the ecliptic, Mars is over 45° up in the south- westward along the ecliptic, Mars is over 45° up in the southeast. The Red Planet is 2.7° above 20 Cet. Saturn is south-southeast, 2.9° to the to the upper right of 20 Cet. over 12° up in the southwest, 7.0° to the upper left of bright Saturn is about 13° up in the southwest, 6.9° to the upper Jupiter. Can you still find Jupiter at this time interval before left of bright Jupiter, now less than 8° in altitude. Start sunrise? Fifteen minutes later, Mercury (m = 0.8) is over 4° looking for the five naked eye planets with the crescent up in the east-northeast, 9.3° to the lower left of the moon. To see the Classic 9 Planets, begin around midnight crescent moon. You may need a binocular to see it. Can you during the next several mornings as described in the mid- find all five naked-eye planets at this time? Procyon (α CMi, month notes. The optimal view that includes the crescent m = 0.4) has the same ecliptic longitude as the sun today, moon is on the morning of July 19. Forty-five minutes although the star is 16° below the ecliptic. In the evening, before sunrise, Mercury (m = 1.1) is 4.0° in altitude in the two hours after sunset, Jupiter is 19.0° in altitude in the east-northeast, over 23° to the lower left of Venus. You’ll south-southeast. Saturn is 7.0° to the lower left of the Giant need a clear horizon to see all 5 naked eye planets, and Planet. In the starfield, Jupiter is 3.9° to the lower right of likely some optical help from a binocular to locate Mercury. 56 Sgr, and 1.5° to the lower left of 50 Sgr. Saturn is 4.2° to Two hours after sunset (about 10:30 p.m. CDT), bright the upper right of σ Cap. Jupiter is nearly 19° up in the south-southeast, 7.0° to the upper right of Saturn. In the starfield, Jupiter is 3.7° to the

July 19: See the five naked-eye planets and the crescent moon simultaneously about 45 minutes before sunrise.

• July 19: GRS: 1:42 a.m. CDT. Forty-five minutes before altitude and Saturn is 7.0° to Jupiter’s upper left. The gap sunrise, see the five naked eye planets with the crescent between the moon and Jupiter is over 170° of ecliptic moon. Brilliant Venus (m = −4.6) is 21° up in the east, 4.5° longitude. Dimmer Uranus, Neptune, and Pluto are to the lower left of Aldebaran. The moon (28.1d, 2%) is scattered along the ecliptic between Venus and Jupiter. about 5° up in the east-northeast, 5.0° to the left of During the next few mornings five planets are visible – Mercury (m = 0.7). The Venus – moon gap is 27°. Mars is along with Uranus, Neptune and Pluto with optical over 47° in altitude in the south-southeast. Jupiter – five assistance – but without the moon. Additionally, Jupiter is days past its opposition – and Saturn, one day before its quickly leaving the sky. On successive mornings, look 3-4 opposition, are in the southwest. Jupiter is about 4° in minutes earlier each day. You may catch all of them in the

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

sky until about July 25. Find clear horizons to view Mercury, the starfield. Saturn is nearly 8° up in the southwest, 7.2° to Saturn, and Jupiter. Two hours after sunset, Jupiter is over the upper left of Jupiter, if you can still see the Giant Planet 19° up in the south-southeast, 7.1° to the upper right of very low in the sky. In the evening, 45 minutes after sunset, Saturn as the giant planet pair continues to retrograde. In the moon (1.4d, 2%) is over 3° up in the west-northwest. the starfield, Jupiter is 4.0° to the lower right of 56 Sgr and Over an hour later, Jupiter is over 20° up in the south- 1.4° to the lower left of 50 Sgr. Saturn is 4.3° to the upper southeast, 4.2° to the lower right of 56 Sgr and 1.2° to the right of σ Cap. lower left of 50 Sgr. The two bright giant planets are 7.2° • July 20: One hour before sunrise, look for Betelgeuse (α Ori, apart. Saturn is to Jupiter’s lower left and 4.4° to the upper m = 0.4) low in the eastern sky, less than 10° to the left of right of σ Cap. the east mark. (To track the brightness of this star, follow @betelbot on Twitter. The account tracks the AAVSO’s observations of Betelgeuse and reports the average magnitude of those observations.) Venus is nearly 18° above Betelgeuse. Orion’s other shoulder, Bellatrix (γ Ori, m = 1.6), is about 12° up in the east. During the next week, begin to look for Rigel (β Ori, m = 0.2), low in the sky, about 15° to the right of the east cardinal point. To view these stars, find a clear horizon. Forty-five minutes before sunrise, Venus, nearly 22° up in the east, is 5.2° to the lower left of Aldebaran and 10.1° to the upper right of Zeta Tauri (ζ Tau, m = 3.0), the Southern Horn of Taurus. Through a telescope, Venus is nearly 32” across; the morning crescent is 35% illuminated. Mercury (m = 0.5), over 23° to the lower left of Venus, is nearly 6° up in the east-northeast. Farther westward along the ecliptic, Mars (m = −0.9) is over 47° up in the south-southeast. The Red Planet is 2.7° to the upper left of 20 Cet. Saturn is over 10° up in the southwest, 7.1° to the upper left of Jupiter. If you have an unobstructed horizon with a clear sky, you may be able to see Jupiter about 3° above the horizon. What is the last date that you July 22: Mercury reaches its greatest morning elongation. see it at this time interval before sunrise? The planets span This chart displays Mercury, Venus and Betelgeuse. nearly 167° of ecliptic longitude. The moon is New at 12:33 • July 22: Seventy-five minutes before sunrise, Jupiter is p.m. CDT. Saturn is at opposition at 5:28 p.m. CDT. This about 6° up in the southwest, with Saturn 7.2° to its upper evening, Saturn rises at sunset, crosses the meridian left. Again, this morning can you track Jupiter as it moves around local midnight, and sets at sunrise tomorrow toward the horizon and locate Mercury (m = 0.2) as it rises morning. Two hours after sunset, Saturn is 17° up in the in the east-northeast. Thirty minutes later, Jupiter is below southeast, 7.1° to the lower left of Jupiter. In the starfield, the horizon. Mercury is over 6° up in the east-northeast. It Jupiter is 4.1° to the lower right of 56 Sgr and 1.3° to the is over 23° to the lower left of Venus. Brilliant Venus is 6.6° lower left of 50 Sgr. Saturn is 4.4° to the upper right of σ to the lower left of Aldebaran and 8.7° to the upper right of Cap. As midnight approaches, Mars is only about 3° up in ζ Tau. Farther eastward along the ecliptic, Mars is over 48° the east, about 74° east of Saturn, now 26° up in the south- up in the south-southeast, 3.1° to the upper left of dimmer southeast. 20 Cet. Mercury reaches its greatest morning elongation • July 21: GRS: 3:20 a.m. CDT, 11:11 p.m. CDT. One hour (20.1°) at 10:12 a.m. CDT. One hour after sunset, the moon before sunrise, Jupiter is about 4° up in the southwest. Can (2.4d, 7%), over 7° up in the west-northwest, is 3.4° to the you see it see it and track it lower in the sky as Mercury rises upper right of Regulus (α Leo, m = 1.3). An hour later, higher in the east-northeast? Forty-five minutes before Jupiter, over 20° up in the south-southeast, is 7.2° to the sunrise, brilliant Venus is over 22° in altitude in the east. upper right of Saturn. In the starfield, Jupiter is 4.3° to the The planet is 5.8° to the lower left of Aldebaran. Mercury lower right of 56 Sgr and 1.0° to the lower left of 50 Sgr. (m = 0.3), over 6° up in the east-northeast, is over 23° to the Saturn is 4.5° to the upper right of σ Cap. lower left of brilliant Venus. Farther westward along the • July 23: Seventy-five minutes before sunrise, Jupiter is less ecliptic, Mars, over 48° up in the south-southeast, is 2.9° to than 6° up in the southwest. Dimmer Saturn is 7.2° to its the upper left of dim 20 Cet. Use a binocular to see Mars in

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

upper left. Looking eastward along the ecliptic, Mars, over upper left of 20 Cet. Through a telescope Mars is nearly 14” 45° up in the south-southeast, is 3.1° to the upper left of 20 across. Saturn is 7.0° up in the southwest. One hour after Cet. Brilliant Venus is farther eastward, about 17° up in the sunset, the crescent moon (5.4d, 34%), over 24° up in the east. It is 7.3° to the lower left of Aldebaran and 8.0° to the west-southwest is 4.0° to the upper left of Gamma Virginis upper right of ζ Tau. If you have clear horizons, you still may (γ Vir, m = 3.4). An hour later, Jupiter is over 21° in altitude be able to see Jupiter very low in the southwest and in the south-southeast, 7.4° to the upper right of Saturn. Mercury (m = 0.1) very low in the east-northeast. By 45 Both planets continue to retrograde in eastern Sagittarius. minutes before sunrise, Mercury is over 6° up in the east- Jupiter is 0.7° to the lower left of 50 Sgr, while Saturn is 3.4° northeast. One hour after sunset, the moon (3.4d, 14%), to the lower left of 56 Sgr. nearly 14° up in the west, is 5.7° to the lower left of Theta • July 26: GRS: 2:27 a.m. CDT, 10:18 p.m. CDT. Two hours Leonis (θ Leo, m = 3.3) and 10.2° to the lower right of before sunrise, four bight planets span the sky from east- Denebola (β Leo, m = 2.1). An hour later, when the giant northeast to the southwest horizon. Venus, 10° up in the planet pair is higher in the sky, Jupiter is nearly 21° up in the east-northeast, is 5.8° to the upper right of ζ Tau. Farther south-southeast. Saturn is 7.3° to the lower left of Jupiter. westward along the ecliptic, Mars, over 42° up in the In the starfield, Jupiter is 4.4° to the lower right of 56 Sgr southeast, is 4.5° to the lower right of ε Psc and 4.3° to the and 0.9° to the lower left of 50 Sgr. Saturn is 4.6° to the upper left of 20 Cet. Farther west, Saturn is nearly 15° in upper right of σ Cap and 3.6° to the lower left of 56 Sgr. altitude in the southwest. Jupiter is 7.4° to Saturn’s lower While Saturn does not pass this star, it is about 1.7° away right. As the sky brightens, the planets shift westward. By from 56 Sgr when the planet stops retrograding in 45 minutes before sunrise, Mercury (m = −0.3) is over 6° in September. altitude in the east-northeast, nearly 25° to the lower left • July 24: GRS: 12:49 a.m. CDT. Have you been tracking the of brilliant Venus. In the evening, one hour after sunset, the five planets in the morning sky? We are nearing the end of thick crescent moon (6.4d, 45%), 27.0° up in the southwest, the interval when all of them are theoretically visible, is 7.2° to the upper left of Spica (α Vir, m = 1.0). An hour assuming a clear horizon in the southwest and east- later (about 10:15 p.m. CDT), Jupiter, over 21° up in the northeast with no clouds. Seventy-five minutes before south-southeast, is 7.4° to the upper right of Saturn. In the sunrise, Jupiter is over 4° in altitude in the southwest, with starfield, Jupiter is 0.7° to the lower left of 50 Sgr. Saturn is Saturn 7.3° to its upper left. Farther east along the ecliptic, 3.4° to the lower left of 56 Sgr. Use a binocular to see the Mars, nearly 47° up in the south-southeast, is 5.6° to the planets against the sidereal background. lower right of Epsilon Piscium (ε Psc, m = 4.2) and 3.6° to • July 27: Venus rises three hours before sunrise. An hour the upper left of 20 Cet. Brilliant Venus is nearly 18° up in later, the brilliant planet is nearly 11° up in the east- the east, 7.3° to the upper right of ζ Tau. Mercury (m = −0.1) northeast. It is 5.1° to the upper right of ζ Tau and 10.3° to is very low in the east-northeast. It rises higher into the sky the lower left of Aldebaran. Farther westward on the as Jupiter sets. By 45 minutes before sunrise, Mercury is ecliptic, Mars, now back in Pisces and over 60° from Venus, over 6° in altitude, about 24° to the lower left of Venus. One is over 43° up in the south-southeast. In the starfield, it is hour after sunset, the moon (4.4d, 23%), over 19° in 5.1° to the lower right of ε Psc and 4.7° to the upper left of altitude in the west-southwest, is 4.3° above Beta Virginis 20 Cet. Farther west, bright Jupiter is nearly 9° up in the (β Vir, m = 3.6). An hour later as the moon is closer to the southwest, with Saturn 7.4° to its upper left. As morning western horizon, Jupiter is 21.0° up in the south-southeast, twilight illuminates the eastern sky, Mercury rises higher in 7.3° to the upper right of Saturn. In the starfield, Jupiter is the east-northeastern sky. Forty-five minutes before 0.8° to the lower left of 50 Sgr, while Saturn is 3.5° to the sunrise, Mercury (m = −0.4) is over 6.5° up in the east- lower left of 56 Sgr. northeast, over 25° to the lower left of brilliant Venus. Can • July 25: The moon is at perigee at 12:02 a.m. CDT, when it you find Castor and Pollux to the left of Mercury? If you is 228,889 miles away. Ninety minutes before sunrise, the don’t see them this morning, what is the first date that you planets, Venus – Jupiter, span nearly 148°. Jupiter is over 4° see them in the morning sky? When Gemini rises, Castor is in altitude in the southwest. Thirty minutes later, Venus is above Pollux. You may need a binocular to initially see them. over 20° in altitude in the east, 6.5° to the upper right of ζ The stars are 4.5° apart. Mercury is over 12° to the lower Tau. Through a telescope, Venus’ morning crescent phase right of Castor. About two weeks ago, the Twins had their is illuminated 39%. The planet is nearly 30” across. Mercury “solar conjunctions.” They have a higher declination than (m = −0.2) is only 4° up in the east-northeast, over 24° to the sun, so they return quickly to the morning sky. In the lower left of Venus. Farther east along the ecliptic, Mars comparison, Sirius had the same celestial longitude as the (m = −1.0) is over 48° in altitude in the south-southeast. The sun on July 5. Because it has a more southerly declination Red Planet is 5.5° to the lower right of ε Psc and 4.0° to the than the sun, the nighttime’s brightest star does not make

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

its first appearance in the morning sky until mid-August. upper left of Antares (α Sco, m = 1.0). Jupiter is nearly 40° The moon reaches its First Quarter phase at 7:33 a.m. CDT. to the lower left of the lunar orb. An hour later, Jupiter is One hour after sunset, the slightly gibbous moon (7.4d, over 22° up in the south-southeast, 7.6° to the upper right 56%), nearly 30° up in the south-southwest, is 3.2° to the of Saturn. In the starfield, Jupiter is 0.5° below 50 Sgr, while upper right of Zubenelgenubi (α Lib, m = 2.8). An hour later, Saturn is 3.2° to the lower left of 56 Sgr. Jupiter – nearly 70° to the left of the moon – is nearly 22° in • July 30: Two hours before sunrise, brilliant Venus is over 11° altitude in the south-southeast, 7.5° to the upper right of up in the east-northeast, 2.9° to the right of ζ Tau. Through Saturn. The Jupiter – Saturn gap continues to grow as the a telescope, the planet is a morning crescent phase, 42% planets retrograde. In the starfield, Jupiter is 0.6° to the illuminated, that is nearly 28” across. Venus, Mars, Saturn, lower left of 50 Sgr, and Saturn is 3.3° to the lower left of and Jupiter stretch across the sky, spanning over 152° of 56 Sgr. ecliptic longitude. Mars, 14” across through a telescope, is • July 28: GRS: 4:05 a.m. CDT, 11:56 p.m. CDT. Two hours nearly 45° in altitude in the southeast. In the starfield, it is before sunrise, four bright planets stretch across the sky 4.9° below ε Psc. Saturn is farther west, about 12° up in the from the east-northeast horizon to the southwest skyline. southwest. It is 7.6° to the upper left of bright Jupiter that Venus continues to move eastward through Taurus. This is less than 6° in altitude. Next month, Jupiter is not visible morning, the brilliant planet, nearly 11° up in the east- at this time interval as it continues to set earlier. Saturn northeast, is 4.3° to the upper right of ζ Tau. Nearly 65° soon follows Jupiter’s departure from the predawn sky. As westward along the ecliptic, Mars is nearly 44° up in the twilight progresses, Mercury (m = −0.7) rises into view. By southeast. In the starfield, it is 5.1° to the upper left of 20 45 minutes before sunrise, this speedy planet is about 6° up Cet and 5.0° below ε Psc. Looking toward the southwest, in the east-northeast, over 27° to the lower left of Venus. Saturn is over 13° in altitude, 7.5° to the upper left of Jupiter, Mercury is 7.9° to the lower right of Pollux. In the evening, only about 7° in altitude. One hour before sunrise, notice about one hour after sunset, the moon (10.4d, 86%), about that Betelgeuse, Bellatrix, Rigel and Orion’s belt are visible 24° up in the south, is over 15° to the upper left of Antares low in the eastern sky. Fifteen minutes later, Mercury (m = and nearly 26° to the upper right of Jupiter. The Giant −0.5), 26.0° to the lower left of Venus, is over 6° up in the Planet is nearly 17° up in the southeast. Saturn is 7.6° to east-northeast. This speedy planet is 9.8° to the right of Jupiter’s lower left. In the starfield, Jupiter is 0.5° to the Pollux. You may need a binocular to see Castor and Pollux. lower right of 50 Sgr, while Saturn is 3.1° to the lower left In the evening – one hour after sunset – the moon (8.4d, of 56 Sgr. The outer planet pair continues to retrograde in 68%) is over 28° up in the south-southwest. The brightening eastern Sagittarius. gibbous moon is 6.5° to the right of Beta Scorpii (β Sco, m = • July 31: GRS: 1:34 a.m. CDT. The morning planet parade 2.5). You may need to block the moon’s light to see the star. spans the sky along the ecliptic. Two hours before sunrise, An hour later, the outer planet pair is in the south- Venus is nearly 12° up in the east-northeast, 2.3° to the southeast. Bright Jupiter is 22.0° in altitude, 7.5° to the right of ζ Tau. Farther westward, Mars is over 45° up in the upper right of Saturn. In the starfield, Jupiter is 0.5° to the southeast, 4.9° below ε Psc. The Red Planet ends the month lower left of 50 Sgr. Saturn is 3.2° to the lower left of 56 Sgr. in southeastern Pisces, near the Pisces – Cetus border. • July 29: The morning planet parade continues from horizon During the month, Mars moved eastward among the stars to horizon with five naked-eye planets visible during the nearly 16° of ecliptic longitude. Saturn is low in the predawn hours. The Classic 9 planets are visible, with southwest, 11.0° in altitude. It is 7.6° to the upper left of optical aid starting after midnight, but not simultaneously bright Jupiter that is over 5° in altitude. Later during twilight, as they were 10 days ago. Two hours before sunrise, about 45 minutes before sunrise, Mercury (m = −0.8) is over brilliant Venus is over 11° up in the east-northeast, 3.6° to 5° up in the east-northeast. Mercury is nearly the same the upper right of ζ Tau. Farther westward along the ecliptic, brightness as Mars, but Mercury’s intensity is diminished by Mars is over 44° up in the southeast, 4.9° below ε Psc. Mars its low altitude. It is over 28° to the lower left of Venus and is in southeast Pisces. Saturn is over 12° up in the southwest, 7.1° to the lower right of Pollux. The length of daylight 7.5° to the upper left of Jupiter. The Giant Planet is less than diminished nearly 45 minutes during the month. The length 7° in altitude. As the sky brightens, Jupiter sets and Mercury of darkness – the interval between the end of evening (m = −0.6) rises into view in the east-northeast. At forty-five twilight to the beginning of morning twilight – is 5.75 hours. minutes before sunrise, this speedy planet is about 6° up in One hour after sunset, the bright gibbous moon (11.4d, the east-northeast. With a binocular note that it is 8.9° to 93%), nearly 20° up in the south-southeast, is 12.0° to the the right of Pollux and nearly 27° to the lower left of brilliant upper right of Jupiter. With a binocular note that the bright Venus. In the evening, one hour after sunset, the gibbous moon is 1.6° to the left of Kaus Borealis (λ Sgr, m = 2.8), the moon (9.4d, 78%), nearly 27° up in the south, is 5.3° to the star at the top of the lid of the Teapot of Sagittarius. Jupiter

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

is over 17° in altitude in the southeast, 7.7° to the upper math, but without logarithms. There is an exponent right of Saturn. The planets, both past their oppositions, calculation and a square root operation that can be handled continue to retrograde in eastern Sagittarius. During July, by the calculator function of a smart phone or a computer. Jupiter retrograded nearly 4° of ecliptic longitude while When I worked with high school students with limited Saturn moved over 2°. In the starfield, use a binocular to mathematics skills, I used values that they could determine observe that Jupiter is 0.5° to the lower right of 50 Sgr, without a calculator. Working with the concepts provided while Saturn is 3.1° to the lower left of 56 Sgr. stronger understanding of the magnitude scale and its relationship to brightness. At month’s end when morning twilight begins (3:50 a.m. The calculation is based on the principles of the CDT), four naked-eye planets arc across the sky, from Venus magnitude system, comparisons of areas, and reducing in the east-northeast to Jupiter in the southwest. The heart of fractions. First assume that the dimmest magnitude visible to our great Milky Way galaxy is below the horizon, but the spine the human eye is magnitude 6.5 and the largest the eye can and its river of stars emerges from the southwest horizon, dilate is 7 mm. Each increment on the magnitude scale is a through nearly overhead, and down into the east-northeast brightness change of 2.512 times. A star of magnitude 3.0 is horizon. Along the way it pierces the Summer Triangle. 2.512 times brighter than a star of magnitude 4.0. A change Cygnus appears to be flying along the ribbon of light. In the of 5 magnitudes is 100x change in brightness (2.5125 = 100). A northeast, it runs through Cassiopeia and through the fish- star with a magnitude of 1 is 100 times brighter than a star of hook shape of Perseus. As it merges with the horizon, the magnitude 6. glow passes between Capella and Venus. In the east, the The second idea is comparison of areas. The area of a Pleiades that are about the same altitude as Capella, catch our circle is calculated as πr2, where r is the radius of the circle. To eye. Aldebaran and the Hyades are lower in the eastern sky, see a star of magnitude 11.5, 5 magnitudes dimmer than what between the Pleiades tiny dipper shape and brilliant Venus. can be seen with the unaided eye (magnitude 6.5), the light Mars is brightly shining in the southeast. The Great collector has to collect 100 times more light than what we see Andromeda Spiral, now over two-thirds of the way up in the without the telescope. The area of the light collector must sky, is high in the southeast, with its namesake’s stars pointing have 100 times more area than the area of the dilated human toward Perseus as they leave the Great Square of Pegasus. eye. We compare the areas. The area of the telescope (At = The Big Dipper now scrapes along the northern horizon as it 2 2 πrt ) is divided by the area of the eye at full dilation (Ae = πre ). does during an autumn evening, now likely blocked from view If we compare (divide) the areas, At/ Ae, we can cancel the π by a neighbor’s house or a fully leafed tree. Daylight 2 2 in the comparison, so we get rt / re . diminished by nearly 45 minutes during the month, and the The third idea is reduction of fractions. The fraction sun’s noon altitude fell 5°. At the end of evening twilight, the above is the value in its lowest terms. Now consider the bright gibbous moon is in the southern sky along with Jupiter fraction rewritten in a multiple of each term, such as 2. Twice and Saturn. Some patience is needed to find the dimmer stars, the radius is the diameter of the light collector, such that especially since the moon’s light blots out most of Sagittarius. 2 2 Dt /De is the fraction. It does not matter the value of the The lunar orb as near the top of the Teapot’s lid. The Milky factor because it cancels in the final result. The factor of 2 Way is impossible to see with this light but pick out the yields a meaningful answer, the diameter of the aperture of brightest stars. Spica is in the west-southwest, while topaz the telescope. Arcturus shines from higher in the sky. Antares, the Heart of Continue with the calculation. The denominator becomes the Scorpion, is in the south-southwest, to the right of the 49, the diameter of the dilated eye squared. For this example, moon. The Summer Triangle dominates the eastern sky, with round this to 50 because the math is easier. The equation Vega near the zenith. On darker nights, the Milky Way can be 2 becomes Dt /50 = 100. Multiply both sides of the equation by seen passing between Altair and Vega, and surrounding 2 50, Dt = 5000. Then taking the square root of both sides, Dt = Deneb, now two-thirds of the way up in the sky in the east- 71mm. A 71mm aperture telescope is needed to see an object northeast. The other galactic markers are Cassiopeia, about a of magnitude 11.5, 5 magnitudes, 100 times, dimmer than the third of the way up in the east-northeast, and Perseus, below human eye can see. the Queen and near the horizon. Pegasus is low in the eastern For my Pluto estimate described earlier in the article: sky. The Big Dipper is about halfway up in the northwest. The haunches of Leo that includes Denebola is low in the sky, just - Pluto is magnitude 14.3 during July 2020. It is 7.8 above the western horizon. magnitudes dimmer than the human eye can see. - Pluto is 2.5127.8 = 1,319 times dimmer than the human eye Here’s my back of the envelope calculation for the can see. The light collector’s area must be 1,319 times minimum aperture (size of the light collector) needed to see 2 larger than the human eye. The equation becomes Dt /49 = a desired magnitude. This is a conceptual idea with some

Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

1,319. When the algebra and the square root are finished, About the Author: Jeffrey Hunt has had a life-long interest in the telescope’s diameter (aperture) is 254mm, 10 inches. astronomy and astronomy education. He has taught astronomy at all levels, from preschool students to university This seems quite large when the calculation revealed a courses. Jeff is a former director of the Waubonsie Valley High 71mm telescope to see magnitude 11.5. Let’s check the School Planetarium in Aurora, Illinois. Dr. Hunt holds several answer compared to the 71mm telescope in the explanation degrees, including a master’s degree in planetarium above. The magnitude difference is a 13.2 times change in education from Michigan State University. He writes an brightness (2.5122.8 = 13.2). That corresponds to a 3.63 times astronomy blog (http://jeffreylhunt.wordpress.com) showing (√13.2) increase in the aperture needed to see magnitude easily seen sky events. Currently, he is retired with his wife and 14.3 compared to magnitude 11.5. The result is that 71mm x cat in Northern Illinois. 3.63 is 258mm, the 10-inch aperture telescope. July has many observing opportunities to see bright planets and dim planets as well as magnificent deep sky objects. Happy observing!

RENEWING YOUR TCAA MEMBERSHIP

The TCAA works to promote in every way among its members and the public an interest in and knowledge of astronomy and its allied sciences, to advance amateur astronomy and observational techniques, to render assistance to other individuals or organizations working in the same or related fields, and to do everything necessary and proper to further such on a formal or informal basis. The TCAA is a Federally recognized non-profit entity organized exclusively for educational and scientific purposes within the meaning of Section 501(c)(3) of the Internal Revenue Service code. The TCAA currently supports family-friendly public observing sessions at SGNC, public outreach events such as the recent May 9, 2016 transit of Mercury and the August 21, 2017, total solar eclipse field trip, hosting of NCRAL meetings (2010 and 2016), and education courses for our membership and the public. The TCAA maintains three observatories, including payment of insurance, and publishes an award-winning club newsletter. We support Sugar Grove Nature Center through its membership program, maintain a loaner telescope program, and provide many other benefits as outlined in our recently revised TCAA Guide #2 – TCAA Membership and Benefits. Your TCAA membership supports education and public outreach in Central Illinois and regions beyond. Membership dues and the generosity of its members are the club’s primary means of financial support. We receive no grants or public funds. We have unmet needs. By renewing your membership when it comes due, you can help to ensure our continuing efforts.

ONLINE PUBLIC TALKS FOR 2020

While our public viewing sessions for 2020 have been cancelled due to the coronavirus pandemic, the talks have not been cancelled. Talks are being made available over Facebook and YouTube.

July 18: Jupiter & Saturn (Mark Boulware)

Jupiter and Saturn offer stark contrasts when compared to the inner planets. We will review how and why they formed in their current locations and their impact on the formation of the rest of the solar system. We will learn how the two greatest planets are similar yet different.

August 22: Touring the Milky Way (Mark Cabaj)

The Milky Way is one of the countless stellar islands floating in a cosmic foam of dark matter, dark energy, and matter. Humanity is trying to find out what our galaxy looks like inside and out using ingenious observing methods and increasingly more sensitive equipment. Take a tour of our “cosmic home” to see what we know so far.

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Vol. 45, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2020

September 19: The ISS: Past, Present, and Future (Sandullah Epsicokhan)

The International Space Station (ISS) is humankind’s largest artificial satellite. Given the right time and conditions, it can be easily seen orbiting overhead. We will look at how it was constructed, how it is used, what it is like living in space, and where it is headed in the future.

October 17: Missions to Mars (Lee Green)

As we reach our closest approach to Mars for the year, the Red Planet shines brightly throughout the evening. Let’s review the many spacecraft missions we’ve sent there, what they are revealing, and how they are paving the way for a future manned mission to Mars.

TCAA TREASURER’S REPORT AS OF JUNE 26, 2020

Checking Account Information

Memo Category Amount BALANCE 05/28/2020 2,594.51 Mark Boulware Dues Received 40.00 Sunil Chebolu Dues Received 40.00 James Wolf Dues Received 39.80 Electrical Service Waynesville Observatory (45.75) BALANCE 06/26/2020 2,668.56

Checking Account Balance – June 26, 2020 $2,668.56 Savings Account Balance – June 26, 2020 $1,968.02 - Includes $0.01 cents interest as of this date

Total TCAA Funds – June 26, 2020 $4,636.58

All transactions are reconciled with the bank statements as of this date. Respectfully submitted, Dave Osenga, Treasurer