For August 2020, waxing gibbous moon passes 1.5 degrees south of Jupiter on Aug. 1, then two degrees south of Saturn the next evening. The full moon, the Green Corn Moon, occurs on Aug. 3. On Aug. 9, the waning gibbous moon passes 1.5 degrees south of rapidly brightening Mars in the dawn sky. The last quarter moon is Aug. 11, and will not interfere much with the peak of the Perseid meteor shower on the next two mornings. You may see about a meteor a minute streaming out of the northeast sky after midnight. The waning crescent moon passes four degrees north of half-lit Venus on Aug. 15. The new moon is on Aug. 18. The first quarter moon is Aug. 25. The waxing gibbous moon catches up to the Jovian giants again at month’s end, passing 1.6 degrees south of Jupiter on Aug. 28, then two degrees south Saturn on the 30th.
While the naked eye, dark adapted by several minutes away from any bright lights, is a wonderful instrument to stare up into deep space, far beyond our own Milky Way, binoculars are better for spotting specific deep sky objects. For a detailed map of northern hemisphere skies, visit www.skymaps.com.
Mercury is too close to sun for viewing this month, but Venus reached greatest brilliancy last month, and dominates the dawn. Pulling away from us, she turns from the crescent at start of August to half-lit at Greatest Western Elongation on Aug. 12. She will be waxing gibbous in the dawn for the rest of the year.
Mars is being overtaken by us, and gets closer, bigger, and brighter until we overtake it at opposition in October. It is close enough now to reveal details in amateur scopes for early risers.
Jupiter and Saturn both reached opposition last July, and are well placed for viewing in the evening now in the southeastern sky. Jupiter is still well placed for viewing in Capricornus. The Great Red Spot is easy to spot with small telescope, as are the four larger moons. Much more distant, fainter Saturn is also in Capricornus, just east of brighter Jupiter. Enjoy the rings, now 22 degrees open and tilted toward earth and sun. Look closer and you may see its huge moon Titan, the most earth-like surface geology elsewhere in the solar system!
The Big Dipper rides high in the northwest at sunset, but falls lower each evening. Good scouts know to take its leading pointers north to Polaris, the famed Pole Star. For us, it sits 30 degrees (our latitude) high in the north, while the rotating earth beneath makes all the other celestial bodies spin around it from east to west.
Taking the arc in the Dipper’s handle, we “arc” southeast to bright orange Arcturus, the brightest star of Spring. Cooler than our yellow Sun, and much poorer in heavy elements, some believe its strange motion reveals it to be an invading star from another smaller galaxy, now colliding with the Milky Way in Sagittarius in the summer sky. Moving almost perpendicular to the plane of our Milky Way, Arcturus was the first star in the sky where its proper motion across the historic sky was noted, by Edmund Halley.
Spike south to Spica, the hot blue star in Virgo. From Spica curve to Corvus the Crow, a four sided grouping. It is above Corvus, in the arms of Virgo, where our large scopes will show members of the Virgo Supercluster, a swarm of over a thousand galaxies about 50 million light years away from us.
Hercules is overhead, with the nice globular cluster M-13 marked on your sky map and visible in binocs. It is faintly visible with the naked eye under dark sky conditions.
The brightest star of the northern hemisphere, Vega dominates the northeast sky. Binoculars reveal the small star just to the northeast of Vega, epsilon Lyrae, as a nice double. Larger telescopes at 150X reveal each of this pair is another close double, hence its nickname, the “double double”…a fine sight under steady sky conditions.
Below Vega are the two bright stars of the Summer Triangle; Deneb is at the top of the Northern Cross, known as Cygnus the Swan to the Romans. It is one of the most luminous stars in our Galaxy, about 50,000 times brighter than our Sun. To the south is Altair, the brightest star of Aquila the Eagle. If you scan the Milky Way with binocs or a small spotting scope between Altair and Deneb, you will find many nice open star clusters and also a lot of dark nebulae, the dust clouds from which new stars will be born in the future.
To the southeast, Antares is bright in the heart of Scorpius. It appears reddish (its Greek name means rival of Ares or Mars to the Latins) because it is half as hot as our yellow Sun; it is bright because it is a bloated red supergiant, big enough to swallow up our solar system all the way out to Saturn’s orbit! Just above the tail of the Scorpion are two fine naked eye star clusters, M-7 (discovered by Ptolemy and included in his catalog about 200 AD) and M-6, making one of the best binocular views in the sky. Your binoculars are ideally suited to reveal many fine open star clusters and nebulae in this region of our Galaxy. Get a dark sky site, and use the objects listed on the back of the August 2019 SkyMap printout to guide you to the best deep sky wonders for binoculars and small telescopes.
East of the Scorpion’s tail is the teapot shape of Sagittarius, which marks the heart of our Milky Way galaxy. Looking like a cloud of steam coming out of the teapot’s spout is the fine Lagoon Nebula, M-8, easily visible with the naked eye.
Just east of these young star birthplaces is the fine globular cluster M-22, faintly visible to the naked eye and spectacularly resolved in scopes of 8” or larger aperture. Look just east of the top star in the teapot of Sagittarius with binoculars.
For more information on the Escambia Amateur Astronomers, visit www.eaaa.net , join us on Facebook or call our sponsor, Lauren Rogers at Pensacola State College at (850) 484-1155, or e-mail her at the college at lrogers@pensacolastate.edu. All EAAA events are free and open to the public.