Explore 12 Great Lunar Targets Sharpen Your Observing Skills on the Moon’S Craters, Lava Flows, and an Elusive Letter X

Total Page:16

File Type:pdf, Size:1020Kb

Explore 12 Great Lunar Targets Sharpen Your Observing Skills on the Moon’S Craters, Lava Flows, and an Elusive Letter X Small-scope wonders 11 7 Explore 12 great lunar targets Sharpen your observing skills on the Moon’s craters, lava flows, and an elusive letter X. 2 1 by Michael E. Bakich he Moon offers something for every observer. It has a face that’s always changing. Following it telescopically T through a lunar month can be fascinating. Ironically, when the Moon is brightest (Full Moon) is the worst time to view it. From our perspective, the Sun is shining on the Moon from a point directly behind us, minimizing shad- ows and thus revealing scant detail. 4 The best lunar viewing times are from when the thin cres- 5 cent becomes visible after New Moon until about 2 days after First Quarter (evening sky) and from about 2 days before Last Quarter to almost New Moon (morning sky). Shadows are lon- ger then, and features stand out in sharp relief. 8 This is especially true along the Moon’s shadow line — called the terminator — which divides the light and dark portions. Before Full Moon, the terminator shows where sunrise is occur- 12 ring; after Full Moon, it marks the sunset line. 6 10 Along the terminator, you’ll see mountaintops protruding high enough to catch sunlight while the dark lower terrain sur- rounds them. On large crater floors, you can follow “wall shad- ows” cast by sides of craters hundreds of feet high. All these 1 Archimedes Crater lies at 30° north latitude centered between the features seem to change in real time, and the differences you eastern and western limbs. This 52-mile-wide (83 kilometers) impact crater lies just northwest of the Moon’s largest mountain range, can see in one night are striking. the Montes Apenninus. Through an 8-inch or larger telescope, scan Archi- The Moon orbits Earth approximately every 27.3 days. medes’ floor for a large number of craterlets. For the best view of this cra- Plotted here are the loca- tions of this story’s 12 features. Because Earth also orbits the Sun, the Moon and Sun line up ter, observe around First Quarter. North is up in all images. Alan Friedman 3 9 Just match the number with the roughly every 29.5 days. The changing positions of the Moon picture, point your telescope at that with respect to the Sun cause the Moon, as seen from Earth, to spot, and you’re on your way to observing cycle through a series of phases. One complete set of phases is a the Moon. North is up in this image. Lick Observatory lunar month. By definition, the lunar month begins at New Moon. We can’t see New Moon from Earth because, at that time, the Moon’s lit side faces the Sun. The Moon then is also quite near the Sun in the sky. Observing tips The Moon is a brilliant object through a telescope. Many observers employ either neutral density filters or variable polar- izing ones to reduce the light. I prefer the latter because you can change the amount of light filtered. My late observing friend, Jeff Medkeff, introduced me to a better way, however. Turn on a white light when observing the Moon between First Quarter and Full. The addition of light suppresses the eyes’ tendency to dark adapt and causes the eye to use normal (scotopic) vision, which is of much higher quality 3 Clavius Crater ranks as the third-largest crater on the Moon’s near- than dark-adapted (photopic) vision. side. It’s visible to the naked eye and spans 140 miles (225 km). But 4 Copernicus Crater is one of the Moon’s most famous formations. Lunar observers usually don’t use color filters. However, I do 2 Sinus Iridum, the Bay of Rainbows, on the Moon’s northwestern it’s what’s in Clavius that I suggest you observe. Look for the crater chain This impact marks the center of a system of bright rays that extends have some friends who have noted a darkening of the lunar edge, spans a whopping 162 miles (260 km). Flanking Sinus Iri- of decreasing size that begins at Clavius’ eastern wall. Oblong Rutherfurd for up to 500 miles (800 km). Copernicus measures 58 miles (93 km) wide. dum to the north is the C-shaped mountain range Montes Jura. Crater measures 33.5 miles by 30 miles (54 km by 48 km). Following it are Because of its great depth — 12,300 feet (3,750 meters) — sunrise and basalt when they use a red filter. A red filter also can help Numerous craterlets dot Sinus Iridum’s remarkably flat surface. The Clavius D (17 miles [28 km]), C (13 miles [21 km]), N (8 miles [13 km]), J (7.5 sunset shadows here create dramatic relief. The central peak rises 3,940 largest is Laplace A, named for Laplace Promontorium, the bright miles [12 km]), and JA (5 miles [8 km]). In addition to those, numerous cra- feet (1,200m) above the crater’s floor. Copernicus’ outer wall gives it a Michael E. Bakich is a senior editor of Astronomy. point that terminates the top of the “C.” Alan Friedman terlets that will test any size telescope dot Clavius’ floor. David Tyler peculiar hexagonal shape. Paolo Lazzarotti © 2010 Kalmbach Publishing Co. This material may not be reproduced • 60 Astronomy Octoberin any 09 form without permission from the publisher. www.Astronomy.com www.Astronomy.com 61 Pitatus Crater, which spans 60 miles (97 km), contains features Torricelli Crater appears pear-shaped at first glance because its west- Gassendi Crater, whose long axis measures 68 miles (110 km) Moretus Crater sits in a heavily impacted region near the Moon’s 10 strewn about its wide floor. A low central peak sits just to the north- 5 ern wall is open and connects to a smaller crater. Both structures lie in 6 across, is a spot that will hold your attention. Numerous clefts, hills, 9 south pole. When the Sun angle is low here, you’ll easily spot the cen- west of the crater’s center. Through an 8-inch telescope, look for the thin the upper part of a low-contrast circular formation named Torricelli R. The and central mountains interrupt its floor. To the north, the crater desig- tral peak that rises 1.3 miles (2.1 km) above the surrounding floor. Moretus grooves called Rimae Pitatus on the western floor. More than 20 lettered prominent crater to the east is 6.8-mile-wide (11 km) Torricelli A. Torricelli nated Gassendi A has broken its wall. Together, both craters give the measures 71 miles (114 km) wide. Note that Cysatus Crater immediately to (catalogued) craterlets surround Pitatus. Also be sure to observe the Crater measures 14.3 miles (23 km) across. Paolo Lazzarotti appearance of a diamond ring, especially at low magnification. Alan Friedman Moretus’ north is deeper, so it still lies in shadow in this image. David Tyler double-walled crater Hesiodus A directly to the west of Pitatus. Alan Friedman Plato Crater lies at the Moon’s top center for observers. Plato spans The Lunar X, also known as the Purbach or Werner Cross, appears at Messier and Messier A are two small craters that sit on the Moon’s 11 63 miles (101 km) and has one of the darkest crater floors on the 12 First Quarter near the terminator between the craters La Caille, Pur- Lacus Mortis, the Lake of Death, spans 93 miles (150 km) and lies in 8 eastern side only 2° south of its equator. Messier is an oblong crater Moon. Polish astronomer Johannes Hevelius (1611–1687) called Plato the bach, and Blanchinus. It sits 25° south of the Moon’s equator and dead- 7 the Moon’s northeastern quadrant. It contains the 25-mile-wide (40 measuring 5.6 miles by 6.8 miles (9 km by 11 km). Messier A spans 8.1 miles Greater Black Lake. One of the features to observe within this crater is its center left to right. When the Lunar X is visible, sunrise is occurring over km) crater Bürg. Try to spot the rilles to the west (left in this image) of by 6.8 miles (13 km by 11 km). Two linear rays extend westward from Mess- slumped inner wall, especially on the western (left) end. Even a small tele- this region. The X remains visible for only 4 hours, so look carefully! Ohio Bürg, which run for some 60 miles (100 km). Lunar cartographers desig- ier A for more than 60 miles (100 km). If your sky is steady, look for the thin scope at a magnification of about 100x will reveal the largest area, a trian- amateur astronomer Dana Thompson captured this image of the Lunar X nated these collectively as Rimae Bürg. Damian Peach rille Rima Messier, which lies to the northwest of the craters. Anthony Ayiomamitis gular section that caved in millions of years ago. Alan Friedman January 25, 2007, at 7:33 p.m. EST. Dana Thompson improve the view when the atmosphere is unsteady. It reduces maria are lower in altitude than the highlands. The dark mate- crater they can see or how many small craters in a given area Dust off your scope the Moon’s brightness as well. rial inside the maria is solidified basaltic lava from periods of they can observe through a particular telescope. One of the best ways to familiarize yourself with the Moon is to Two other methods can reduce the Moon’s brightness: high volcanism up to about a billion years after the Moon formed.
Recommended publications
  • Craters in Shadow
    Section 3: Craters in Shadow Kepler Copernicus Eratosthenes Seen it Clavius Seen it Section 3: Craters in Shadow Visibility: A pair of binoculars is the minimum requirement to see these features. When: Look for them when the terminator’s close by, typically a day before last quarter. Not all craters are best seen when the Sun is high in the lunar sky - in fact most aren’t! If craters aren’t par- ticularly bright or dark, they tend to disappear into the background when the Moon’s phase is close to full. These craters are best seen when the ‘terminator’ is nearby, or when the Sun is low in the lunar sky as seen from the crater. This causes oblique lighting to fall on the crater and create exaggerated shadows. Ultimately, this makes the crater look more dramatic and easier to see. We’ll use this effect for the next section on lunar mountains, but before we do, there are a couple of craters that we’d like to bring to your attention. Actually, the Moon is covered with a whole host of wonderful craters that look amazing when the lighting is oblique. During the summer and into the early autumn, it’s the later phases of the Moon are best positioned in the sky - the phases following full Moon. Unfortunately, this means viewing in the early hours but don’t worry as we’ve kept things simple. We just want to give you a taste of what a shadowed crater looks like for this marathon, so the going here is really pretty easy! First, locate the two craters Kepler and Copernicus which were marathon targets pointed out in Section 2.
    [Show full text]
  • Glossary Glossary
    Glossary Glossary Albedo A measure of an object’s reflectivity. A pure white reflecting surface has an albedo of 1.0 (100%). A pitch-black, nonreflecting surface has an albedo of 0.0. The Moon is a fairly dark object with a combined albedo of 0.07 (reflecting 7% of the sunlight that falls upon it). The albedo range of the lunar maria is between 0.05 and 0.08. The brighter highlands have an albedo range from 0.09 to 0.15. Anorthosite Rocks rich in the mineral feldspar, making up much of the Moon’s bright highland regions. Aperture The diameter of a telescope’s objective lens or primary mirror. Apogee The point in the Moon’s orbit where it is furthest from the Earth. At apogee, the Moon can reach a maximum distance of 406,700 km from the Earth. Apollo The manned lunar program of the United States. Between July 1969 and December 1972, six Apollo missions landed on the Moon, allowing a total of 12 astronauts to explore its surface. Asteroid A minor planet. A large solid body of rock in orbit around the Sun. Banded crater A crater that displays dusky linear tracts on its inner walls and/or floor. 250 Basalt A dark, fine-grained volcanic rock, low in silicon, with a low viscosity. Basaltic material fills many of the Moon’s major basins, especially on the near side. Glossary Basin A very large circular impact structure (usually comprising multiple concentric rings) that usually displays some degree of flooding with lava. The largest and most conspicuous lava- flooded basins on the Moon are found on the near side, and most are filled to their outer edges with mare basalts.
    [Show full text]
  • 8.5 X 13.5 Doublelines.P65
    Cambridge University Press 978-0-521-74128-6 - Exploring the Solar System with Binoculars: A Beginner’s Guide to the Sun, Moon, and Planets Stephen James O’Meara’s Index More information Index Adams, John Couch, 96 Carrington, Richard C., 15 degree of condensation (DC) of, Agesinax, 24 Carroll, Lewis, 60 111–112 Aionwantha (Hiawatha), 45 Ceres, 70, 99–101 estimating the brightness of, Airy, George Biddell, 50, 51, 55 discovery and history as a planet, 111–112 Alcock, George, 116 99–100 In–Out method, 111 Allen, Richard Hinckley, 136 general description of, 99, Modified–Out method, 111–112 Alphonsus VI (King of Portugal), 104 100–101 experience helps in observing, 112 Andersen, Hans Christian, 92 how to find, 101 flaring in brightness, 111 Arago, Francois, 59 Chaikin, Andrew, 54 how to locate and identify, 110 Araki, Genichi, 116 Challis, James, 50 in history, relating to, 103–108 Arend, Silvio, 115 Chambers, George F., 8, 19 King David, 103 Aristotle, 65 Cheshire Cat, 60 Melville’s Moby-Dick, 107–108 Arlt, Rainer, 132 Children of God (cult), 108 Napoleon, 106 Arrehenius, Svente, 78, 79 Chinese Catalogue (Biot’s), 131–132 Shakespeare’s Julius Caesar, 103–104 Arter, T. R., 131 Cicero (Roman emperor), 77 the broadside of the comets of Asteroid Belt, 101 City of God, The, 90 1680 and 1682, 104 brightest objects in, 101–102 Collins, Peter, 116 the death of Julius Caesar, 104 asteroids Cometographia, 103 the Middle Ages, 104 2003 EH1, 131 comets, 103–117 the Old Testament?, 103 3200 Phaeton, 142 1P (Halley), 103, 109, 114–115, the whaling ship
    [Show full text]
  • Sky and Telescope
    SkyandTelescope.com The Lunar 100 By Charles A. Wood Just about every telescope user is familiar with French comet hunter Charles Messier's catalog of fuzzy objects. Messier's 18th-century listing of 109 galaxies, clusters, and nebulae contains some of the largest, brightest, and most visually interesting deep-sky treasures visible from the Northern Hemisphere. Little wonder that observing all the M objects is regarded as a virtual rite of passage for amateur astronomers. But the night sky offers an object that is larger, brighter, and more visually captivating than anything on Messier's list: the Moon. Yet many backyard astronomers never go beyond the astro-tourist stage to acquire the knowledge and understanding necessary to really appreciate what they're looking at, and how magnificent and amazing it truly is. Perhaps this is because after they identify a few of the Moon's most conspicuous features, many amateurs don't know where Many Lunar 100 selections are plainly visible in this image of the full Moon, while others require to look next. a more detailed view, different illumination, or favorable libration. North is up. S&T: Gary The Lunar 100 list is an attempt to provide Moon lovers with Seronik something akin to what deep-sky observers enjoy with the Messier catalog: a selection of telescopic sights to ignite interest and enhance understanding. Presented here is a selection of the Moon's 100 most interesting regions, craters, basins, mountains, rilles, and domes. I challenge observers to find and observe them all and, more important, to consider what each feature tells us about lunar and Earth history.
    [Show full text]
  • Pete Aldridge Well, Good Afternoon, Ladies and Gentlemen, and Welcome to the Fifth and Final Public Hearing of the President’S Commission on Moon, Mars, and Beyond
    The President’s Commission on Implementation of United States Space Exploration Policy PUBLIC HEARING Asia Society 725 Park Avenue New York, NY Monday, May 3, and Tuesday, May 4, 2004 Pete Aldridge Well, good afternoon, ladies and gentlemen, and welcome to the fifth and final public hearing of the President’s Commission on Moon, Mars, and Beyond. I think I can speak for everyone here when I say that the time period since this Commission was appointed and asked to produce a report has elapsed at the speed of light. At least it seems that way. Since February, we’ve heard testimonies from a broad range of space experts, the Mars rovers have won an expanded audience of space enthusiasts, and a renewed interest in space science has surfaced, calling for a new generation of space educators. In less than a month, we will present our findings to the White House. The Commission is here to explore ways to achieve the President’s vision of going back to the Moon and on to Mars and beyond. We have listened and talked to experts at four previous hearings—in Washington, D.C.; Dayton, Ohio; Atlanta, Georgia; and San Francisco, California—and talked among ourselves and we realize that this vision produces a focus not just for NASA but a focus that can revitalize US space capability and have a significant impact on our nation’s industrial base, and academia, and the quality of life for all Americans. As you can see from our agenda, we’re talking with those experts from many, many disciplines, including those outside the traditional aerospace arena.
    [Show full text]
  • JRASC-2007-04-Hr.Pdf
    Publications and Products of April / avril 2007 Volume/volume 101 Number/numéro 2 [723] The Royal Astronomical Society of Canada Observer’s Calendar — 2007 The award-winning RASC Observer's Calendar is your annual guide Created by the Royal Astronomical Society of Canada and richly illustrated by photographs from leading amateur astronomers, the calendar pages are packed with detailed information including major lunar and planetary conjunctions, The Journal of the Royal Astronomical Society of Canada Le Journal de la Société royale d’astronomie du Canada meteor showers, eclipses, lunar phases, and daily Moonrise and Moonset times. Canadian and U.S. holidays are highlighted. Perfect for home, office, or observatory. Individual Order Prices: $16.95 Cdn/ $13.95 US RASC members receive a $3.00 discount Shipping and handling not included. The Beginner’s Observing Guide Extensively revised and now in its fifth edition, The Beginner’s Observing Guide is for a variety of observers, from the beginner with no experience to the intermediate who would appreciate the clear, helpful guidance here available on an expanded variety of topics: constellations, bright stars, the motions of the heavens, lunar features, the aurora, and the zodiacal light. New sections include: lunar and planetary data through 2010, variable-star observing, telescope information, beginning astrophotography, a non-technical glossary of astronomical terms, and directions for building a properly scaled model of the solar system. Written by astronomy author and educator, Leo Enright; 200 pages, 6 colour star maps, 16 photographs, otabinding. Price: $19.95 plus shipping & handling. Skyways: Astronomy Handbook for Teachers Teaching Astronomy? Skyways Makes it Easy! Written by a Canadian for Canadian teachers and astronomy educators, Skyways is Canadian curriculum-specific; pre-tested by Canadian teachers; hands-on; interactive; geared for upper elementary, middle school, and junior-high grades; fun and easy to use; cost-effective.
    [Show full text]
  • Planetary Science : a Lunar Perspective
    APPENDICES APPENDIX I Reference Abbreviations AJS: American Journal of Science Ancient Sun: The Ancient Sun: Fossil Record in the Earth, Moon and Meteorites (Eds. R. 0.Pepin, et al.), Pergamon Press (1980) Geochim. Cosmochim. Acta Suppl. 13 Ap. J.: Astrophysical Journal Apollo 15: The Apollo 1.5 Lunar Samples, Lunar Science Insti- tute, Houston, Texas (1972) Apollo 16 Workshop: Workshop on Apollo 16, LPI Technical Report 81- 01, Lunar and Planetary Institute, Houston (1981) Basaltic Volcanism: Basaltic Volcanism on the Terrestrial Planets, Per- gamon Press (1981) Bull. GSA: Bulletin of the Geological Society of America EOS: EOS, Transactions of the American Geophysical Union EPSL: Earth and Planetary Science Letters GCA: Geochimica et Cosmochimica Acta GRL: Geophysical Research Letters Impact Cratering: Impact and Explosion Cratering (Eds. D. J. Roddy, et al.), 1301 pp., Pergamon Press (1977) JGR: Journal of Geophysical Research LS 111: Lunar Science III (Lunar Science Institute) see extended abstract of Lunar Science Conferences Appendix I1 LS IV: Lunar Science IV (Lunar Science Institute) LS V: Lunar Science V (Lunar Science Institute) LS VI: Lunar Science VI (Lunar Science Institute) LS VII: Lunar Science VII (Lunar Science Institute) LS VIII: Lunar Science VIII (Lunar Science Institute LPS IX: Lunar and Planetary Science IX (Lunar and Plane- tary Institute LPS X: Lunar and Planetary Science X (Lunar and Plane- tary Institute) LPS XI: Lunar and Planetary Science XI (Lunar and Plane- tary Institute) LPS XII: Lunar and Planetary Science XII (Lunar and Planetary Institute) 444 Appendix I Lunar Highlands Crust: Proceedings of the Conference in the Lunar High- lands Crust, 505 pp., Pergamon Press (1980) Geo- chim.
    [Show full text]
  • July 2020 in This Issue Online Readers, ALPO Conference November 6-7, 2020 2 Lunar Calendar July 2020 3 Click on Images an Invitation to Join ALPO 3 for Hyperlinks
    A publication of the Lunar Section of ALPO Edited by David Teske: [email protected] 2162 Enon Road, Louisville, Mississippi, USA Recent back issues: http://moon.scopesandscapes.com/tlo_back.html July 2020 In This Issue Online readers, ALPO Conference November 6-7, 2020 2 Lunar Calendar July 2020 3 click on images An Invitation to Join ALPO 3 for hyperlinks. Observations Received 4 By the Numbers 7 Submission Through the ALPO Image Achieve 4 When Submitting Observations to the ALPO Lunar Section 9 Call For Observations Focus-On 9 Focus-On Announcement 10 2020 ALPO The Walter H. Haas Observer’s Award 11 Sirsalis T, R. Hays, Jr. 12 Long Crack, R. Hill 13 Musings on Theophilus, H. Eskildsen 14 Almost Full, R. Hill 16 Northern Moon, H. Eskildsen 17 Northwest Moon and Horrebow, H. Eskildsen 18 A Bit of Thebit, R. Hill 19 Euclides D in the Landscape of the Mare Cognitum (and Two Kipukas?), A. Anunziato 20 On the South Shore, R. Hill 22 Focus On: The Lunar 100, Features 11-20, J. Hubbell 23 Recent Topographic Studies 43 Lunar Geologic Change Detection Program T. Cook 120 Key to Images in this Issue 134 These are the modern Golden Days of lunar studies in a way, with so many new resources available to lu- nar observers. Recently, we have mentioned Robert Garfinkle’s opus Luna Cognita and the new lunar map by the USGS. This month brings us the updated, 7th edition of the Virtual Moon Atlas. These are all wonderful resources for your lunar studies.
    [Show full text]
  • Facts & Features Lunar Surface Elevations Six Apollo Lunar
    Greek Mythology Quadrants Maria & Related Features Lunar Surface Elevations Facts & Features Selene is the Moon and 12 234 the goddess of the Moon, 32 Diameter: 2,160 miles which is 27.3% of Earth’s equatorial diameter of 7,926 miles 260 Lacus daughter of the titans 71 13 113 Mare Frigoris Mare Humboldtianum Volume: 2.03% of Earth’s volume; 49 Moons would fit inside Earth 51 103 Mortis Hyperion and Theia. Her 282 44 II I Sinus Iridum 167 125 321 Lacus Somniorum Near Side Mass: 1.62 x 1023 pounds; 1.23% of Earth’s mass sister Eos is the goddess 329 18 299 Sinus Roris Surface Area: 7.4% of Earth’s surface area of dawn and her brother 173 Mare Imbrium Mare Serenitatis 85 279 133 3 3 3 Helios is the Sun. Selene 291 Palus Mare Crisium Average Density: 3.34 gm/cm (water is 1.00 gm/cm ). Earth’s density is 5.52 gm/cm 55 270 112 is often pictured with a 156 Putredinis Color-coded elevation maps Gravity: 0.165 times the gravity of Earth 224 22 237 III IV cresent Moon on her head. 126 Mare Marginis of the Moon. The difference in 41 Mare Undarum Escape Velocity: 1.5 miles/sec; 5,369 miles/hour Selenology, the modern-day 229 Oceanus elevation from the lowest to 62 162 25 Procellarum Mare Smythii Distances from Earth (measured from the centers of both bodies): Average: 238,856 term used for the study 310 116 223 the highest point is 11 miles.
    [Show full text]
  • THE SHAPE and ELEVATION ANALYSIS of LUNAR CRATER's TRUE MARGIN. Bo Li1, Zongcheng Ling1, Jiang Zhang1, Zhongchen Wu1, Yuheng
    46th Lunar and Planetary Science Conference (2015) 1709.pdf THE SHAPE AND ELEVATION ANALYSIS OF LUNAR CRATER'S TRUE MARGIN. Bo Li1, Zongcheng Ling1, Jiang Zhang1, Zhongchen Wu1, Yuheng Ni1, Jian Chen1.1 Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment; Insitute of Space Sciences, Shandong University, Weihai 264209, China, ([email protected]). Introduction: Although rare for Earth and other plane- 1(xk-1, yk-1) starting at an arbitrary point P0 (x0, y0). The tary bodies, impact cratering is a common geologic location of the center of the crater C is calculated from process in planetary evolution history. The Moon is its centroid, pockmarked with literally billions of craters, which 푘−1 푥 푘−1 푦 퐶 = 푖=0 푖, 퐶 = 푖=0 푖 range in size from microscopic pits on the surfaces of 푥 푘 푦 푘 rock specimens to huge, circular impact basins with The shape of a depression’s boundary is de- hundreds or even thounds of kilometers in diameter. scribed by the polar function r θ with the origin lo- Recognition and evaluation of the impact processes cated at C. In order to extract depressions’ shapes can provide an essential interpretive tool for under- based on just a few points we calculate its Fourier ex- standing planets and their geologic evolution [1]. The pansion [3]: 푘−1 푠푖푛 (푛∗휃 ) 푘−1 푐표푠 (푛∗휃 ) 푘 regular and irregular shape and morphology of crater 푎 = 푖=0 푖 ; 푏 = 푖=0 푖 ; 푟 = . in different ages retain key information (e.g., impact 푛 푘 푛 푘 0 휋 direction and velocity) of the impact processes during The fourier coefficients ai, and bi pertain to its shape.
    [Show full text]
  • Graphical Evidence for the Solar Coronal Structure During the Maunder Minimum: Comparative Study of the Total Eclipse Drawings in 1706 and 1715
    J. Space Weather Space Clim. 2021, 11,1 Ó H. Hayakawa et al., Published by EDP Sciences 2021 https://doi.org/10.1051/swsc/2020035 Available online at: www.swsc-journal.org Topical Issue - Space climate: The past and future of solar activity RESEARCH ARTICLE OPEN ACCESS Graphical evidence for the solar coronal structure during the Maunder minimum: comparative study of the total eclipse drawings in 1706 and 1715 Hisashi Hayakawa1,2,3,4,*, Mike Lockwood5,*, Matthew J. Owens5, Mitsuru Sôma6, Bruno P. Besser7, and Lidia van Driel – Gesztelyi8,9,10 1 Institute for Space-Earth Environmental Research, Nagoya University, 4648601 Nagoya, Japan 2 Institute for Advanced Researches, Nagoya University, 4648601 Nagoya, Japan 3 Science and Technology Facilities Council, RAL Space, Rutherford Appleton Laboratory, Harwell Campus, OX11 0QX Didcot, UK 4 Nishina Centre, Riken, 3510198 Wako, Japan 5 Department of Meteorology, University of Reading, RG6 6BB Reading, UK 6 National Astronomical Observatory of Japan, 1818588 Mitaka, Japan 7 Space Research Institute, Austrian Academy of Sciences, 8042 Graz, Austria 8 Mullard Space Science Laboratory, University College London, RH5 6NT Dorking, UK 9 LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université Paris Diderot, Sorbonne Paris Cité, 92195 Meudon, France 10 Konkoly Observatory, Hungarian Academy of Sciences, 1121 Budapest, Hungary Received 18 October 2019 / Accepted 29 June 2020 Abstract – We discuss the significant implications of three eye-witness drawings of the total solar eclipse on 1706 May 12 in comparison with two on 1715 May 3, for our understanding of space climate change. These events took place just after what has been termed the “deep Maunder Minimum” but fall within the “extended Maunder Minimum” being in an interval when the sunspot numbers start to recover.
    [Show full text]
  • Lunar Impact Basins Revealed by Gravity Recovery and Interior
    Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements Gregory Neumann, Maria Zuber, Mark Wieczorek, James Head, David Baker, Sean Solomon, David Smith, Frank Lemoine, Erwan Mazarico, Terence Sabaka, et al. To cite this version: Gregory Neumann, Maria Zuber, Mark Wieczorek, James Head, David Baker, et al.. Lunar im- pact basins revealed by Gravity Recovery and Interior Laboratory measurements. Science Advances , American Association for the Advancement of Science (AAAS), 2015, 1 (9), pp.e1500852. 10.1126/sci- adv.1500852. hal-02458613 HAL Id: hal-02458613 https://hal.archives-ouvertes.fr/hal-02458613 Submitted on 26 Jun 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. RESEARCH ARTICLE PLANETARY SCIENCE 2015 © The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. Distributed Lunar impact basins revealed by Gravity under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). Recovery and Interior Laboratory measurements 10.1126/sciadv.1500852 Gregory A. Neumann,1* Maria T. Zuber,2 Mark A. Wieczorek,3 James W. Head,4 David M. H. Baker,4 Sean C. Solomon,5,6 David E. Smith,2 Frank G.
    [Show full text]