25 Amazing Moon Features! STARGAZING GETTING STARTED WITH ASTRONOMY Total Solar Eclipse When's the Next One? P. 7 I Join the Club P. 11 I Up All Night Future Eclipses When’s the Next One? Don’t be surprised if seeing the totally eclipsed Sun is habit-forming. By J. Kelly Beatty but also because you’ll be able to experi- Pacific and Atlantic) and by the impos- ence the glorious stars of the deep- ing ridge of Andean peaks. Some of the very total solar eclipse is different. southern sky (think Southern Cross and very best viewing prospects, statistically E Some are frustratingly short, oth- Alpha Centauri). Moreover, the Andes of speaking, occur in Chile’s picturesque ers luxuriously long. The Sun’s ethereal central Chile boast some of the world’s Elqui Valley, which is a little inland from corona can vary from nearly formless greatest professional observatories. A La Serena, and on the other side of the to astoundingly structured. And the few even lie in the path of totality. Andes in western Argentina. Moon’s umbral shadow, which touches From a climatic viewpoint, it’ll be Having visited La Serena and the Earth about every 18 months on average, the middle of winter in the Southern Elqui Valley in March, I can vouch for can drape itself anywhere on the globe. Hemisphere. But the track crosses South the fact that “eclipse buzz” is already Regardless of the specifics, however, America at subtropical latitudes near 30° building in this area. these celestial spectacles are always south, and the average daytime high in amazing. In fact, a common refrain after La Serena (offering 2m 13s of totality) is DECEMBER 14, 2020: someone’s first full immersion in total- about 60°F. According to eclipse-weather Chile & Argentina Again! ity is, “When’s the next one?!” And so, expert Jay Anderson, this positioning By remarkable coincidence, the Moon’s should you likewise be looking ahead, “takes the sting out of what might other- umbral shadow makes its next return here’s a recap of the circumstances for a wise be a very cloudy environment.” Day- about 17 months later — and again few upcoming total solar eclipses. to-day weather is dominated by ocean- crosses Chile and Argentina in the driven cloudiness offshore (in both the middle of a path that spans the southern JULY 2, 2019: Chile & Argentina There’s no “TSE” in 2018. Instead, nearly two years will pass until your next oppor- North America 19 tunity (after August 21st) to stand in 0 2 the Moon’s shadow. On paper, the solar , North Pacific 2 m s Ocean eclipse of July 2, 2019, offers up to 4 33 ly u of totality, nearly double the maximum J that eclipse goers will witness this year. However, to experience all that you’ll need to be bobbing in a remote stretch of the South Pacific Ocean some 700 South America miles north of Easter Island. And while at least one company is planning to place Path of Totality a ship in totality’s path near the Pitcairn Islands, most veteran eclipse chasers are eyeing locations in the path’s only land- fall: central Chile and Argentina. These are exciting countries to visit, not only because of their welcoming South Pacific populations and amazing natural beauty, Ocean A yellow band marks the path of totality during the next total solar eclipse after the one on August 21st. The path crosses land only in Chile and Argentina. A black dot marks where the duration will be longest. Sets of curved lines Antarctica show the extent of the partial eclipse (in 20% increments). MICHAEL ZEILER / GREATAMERICANECLIPSE.COM / ZEILER MICHAEL 1 America’s 2017 Eclipse Future Eclipses Pacific and Atlantic oceans. However, this year the timing comes in the midst of the Southern Hemisphere’s summer 4 2 — high season for tourism! This means 0 2 chances are good that cruise ships will , 8 il be positioned off the South American r p coast specifically to catch the Moon’s A shadow as it sweeps by. The duration of totality is relatively North America short, a maximum of 2m 10s — but at North Atlantic least this time the point of “greatest Ocean eclipse” occurs on dry land, squarely in North Pacific Ocean the Patagonia region of Argentina. It’s still a bit far off for detailed eclipse-day y weather statistics, but summer months it al ot tend to be much less rainy than winter f T h o months, so on that basis alone there’s Pat cause for optimism. If this eclipse appeals to you, keep an South America eye out for travel packages that provide eclipse-day viewing as part of broader summertime tourism opportunities — such as visits to Chilean wineries or to South Pacific Ocean the Incan citadel of Machu Picchu in neighboring Peru. DECEMBER 4, 2021: Antarctica After going 38 years without being touched by the Moon’s shadow, the mainland U.S. is Truly dedicated eclipse chasers will have getting two total solar eclipses in a 7-year period. The second of these, in 2024, has a path that sweeps up through Mexico before crossing a belt of states from Texas to Maine. the opportunity to demonstrate their mettle one year later, when the Moon’s shadow sweeps over Antarctica and APRIL 8, 2024: What has many early planners excited provides a maximum of 1m 54s of total- United States & Mexico is the possibility of seeing the total solar ity. Xavier Jubier, who almost assuredly If distant travel or being really, really eclipses in both 2017 and 2024 from the will be watching that day, suggests three cold isn’t your thing, take heart. After same location. That’s possible inside a ways — none of them inexpensive — for avoiding the mainland U.S. for 38 years 135-by-85-mile parallelogram of real estate getting into the eclipse track. (1979 to 2017), the Moon’s umbra will just to the southeast of St. Louis. This First, you could hop aboard an make a return pass less than 7 years area includes Carbondale, Illinois, near Ilyushin 76 cargo aircraft that will fly after the total eclipse on August 21st. which is the point of maximum duration from Punta Arenas at the southern tip It’ll be a good one too, with a path for August’s eclipse. So a well-placed of Chile to Union Glacier in Antarctica. that sweeps northeastward from the skywatcher could witness 2m 42s of total- Once there you can stay and observe Pacific and across central Mexico, where ity in 2017 and another 4m 8s in 2024. from the relative comfort of a privately onlookers near Durango are banking on Some of the most dedicated “umbra- owned camp. A second option is to book seeing 4m 28s of totality. The path then philes” have traveled the world to witness a seat on a chartered eclipse flight that climbs through central Texas (Austin dozens of eclipses over their lifetimes. will position you in the Moon’s shadow and Dallas–Fort Worth are in for a treat Will you do likewise? Will totality on high above the Antarctic ice cap (I did that day), and several Midwest states August 21st become the first entry in this in 2003 — it’s a breathtaking way (Indianapolis and Cleveland are like- your personal “life list” of treasured to experience totality). Finally, some wise in the path). Then the track follows moments in the Moon’s shadow? ships are likely to venture into the South the arc of Lake Erie and Lake Ontario, Atlantic from various ports and inter- engulfing Buffalo before moving into J. Kelly Beatty, a senior editor at Sky & cept the shadow shortly after dawn from upstate New York, southern Québec, Telescope, has traveled to 17 total and an- positions off the tip of the Antarctic central Maine (where, with luck, “black- nular eclipses beginning in 1991. On August Peninsula, roughly halfway between the fly season” won’t have started yet), and 21st he’ll be leading a tour of 200+ hopeful Falkland and South Sandwich Islands. Canada’s Maritime provinces. eclipse watchers in Hopkinsville, Kentucky. GREATAMERICANECLIPSE.COM / ZEILER MICHAEL 2 America’s 2017 Eclipse LUNAR SHOWCASE M A R E F R I G O M R I S 8 Endymion Aristoteles Endymion SINUS Platolato 24 Reiner Gamma RORIS 17 Atlastlas 4 Serpentine Ridge ALPS MTSAlpineAlpine SINUS alley Eudoxus Picoico Vvalley Hercules IRIDUMIRIDUM 9 2 Proclus MARE Piton MTS Aristillus MTS IMBRIUM CAUCASUS CAUCASUS Posidonius 21 Archimedes 3 Autolycus MARE Schröter’s Timocharis 10 MARE Cleomedes Valley Cleomedes 22 SERENITATIS Aristarchus 11 1 APENNINE MTSMTS MARE Pliniuslinius CRISIUM OCEANUS Manilius Eratosthenes 18 Kepler Reiner Copernicus MARE Agrippa Reinhold TRANQUILLITATIS PROCELLARUM PROCELLARUM Lansberg MARE Delambre FECUNDITATIS Grimaldi Hipparchusipparchus 25 12 Ptolemaeustolemaeus Langrenus Theophilus 5 Albategniuslbategnius Cyrillus MARE Alphonsuslphonsus MARE Gassendi 23 NUBIUM Catharina NECTARIS StraightStraight WallWall 13 Arzachel Bullialdus Thebit 6 MAREMARE Fracastorius Petavius HUMORUM 14 Purbach Werner Piccolominiiccolomini Walter Fra Mauro Hainzel Altai Scarp 19 Tycho 7 15 Maurolycus Schickard Maginus JannsenJannsen 20 Schiller Pitiscusitiscus Claviuslavius Longomontanus 16 FEATURES APLENTY This composite of Lunar Reconnais- sance Orbiter images reveals the Moon's varied surface features. NASA GODDARD / ARIZONA STATE UNIVERSITY 25 Amazing Moon Features TAKE A TELESCOPIC TOUR OF 4 BILLION YEARS OF SOLAR-SYSTEM HISTORY. By J. KELLY BEATTY Every month we watch the Moon morph And what an interesting face it has! Over time we’ve come through its sequence of phases — from new to full and back to appreciate that the lunar surface preserves geologic events to new.