See what's up in the night sky for August 2020, including stargazing events and the moon's phases, in this Space.com gallery courtesy of Starry Night Software.
Saturday, August 1 all night — Bright Moon below Jupiter and Saturn
The moon's monthly visit with the gas giant planets Jupiter and Saturn will happen on the night of Saturday, Aug. 1. Shortly before dusk, the trio will rise together over the southeastern horizon, with the moon positioned directly below (or to the celestial south of) bright Jupiter. The moon and Jupiter will fit into the field of view of binoculars (red circle). As they cross the sky during the night, the moon will creep east, towards dimmer Saturn, and the diurnal rotation of the sky will move Jupiter below the moon. This conjunction will make a beautiful wide field image in early evening (or in the southwestern sky around 3 a.m. local time), especially when composed with some interesting foreground scenery.
Monday, August 3 at 15:59 GMT — Full Green Corn Moon
The August full moon, colloquially called the "Sturgeon Moon", "Red Moon", "Green Corn Moon", and "Grain Moon", always shines among or near the stars of Aquarius or Capricornus. The moon will be fully illuminated because it is positioned opposite the sun in the sky, causing the moon to rise at sunset and set at sunrise. Since the full phase will officially occur around mid-day Monday in the Americas, the moon will appear to be full on Sunday night, too. But magnified views will reveal a thin strip of darkness along the moon's western and eastern limbs on Sunday and Monday night, respectively.
Tuesday, August 4 all night — Reiner Gamma Lunar Swirl
Oceanus Procellarum is the large, dark mare region near the western (left-hand) limb of the moon. The Reiner Gamma Lunar Swirl is a small, high-albedo area located just inside the western edge of Procellarum, due north of the dark crater Grimaldi and due west of the bright, rayed crater Kepler. It is best seen a night or two after the moon's full phase. The 18 mile or 30 km diameter crater Reiner is located east-southeast of Reiner Gamma. The swirl is composed of ancient lunar basalt that has not been darkened by weathering, likely due to protection from cosmic rays by a strong localized magnetic field — the swirl has one of the strongest magnetic anomalies on the moon! At high magnification, its complex, swirling shape can be discerned.
Thursday, August 6 evening — Comet NEOWISE close to Messier 53
In the western sky after dusk on Thursday, Aug. 6, the path of fading Comet C/2020 F3 (NEOWISE) will carry it closely past the globular star clusters Messier 53 and NGC 5053. Find the trio a finger's width above (or 1 degree to the celestial northeast of) the medium-bright star Diadem, also known as Alpha Comae Berenices. The comet, the star, and the two clusters will all appear together within the field of view of a telescope at low magnification (red circle), offering a nice photo opportunity. The comet will not be as bright as depicted here.
Saturday, August 8 overnight — Waning Moon meets Mars
When the waning gibbous moon rises in the east shortly before midnight on Saturday, Aug. 8, it will be positioned only two finger widths to the lower right (or 2.3 degrees to the celestial southwest of) bright, reddish Mars. The pair, which will fit nicely together in the field of binoculars (red circle), will cross the night sky together. During that period, the moon's eastward orbital motion will carry it closer to Mars, and the diurnal rotation of the sky will shift Mars to the moon's upper right. They will not set in the west until mid-morning on Sunday — offering a chance to see Mars in the morning daytime sky using binoculars and backyard telescopes, by using the moon as a reference. Observers in most of western Antarctica, southeastern South America, and the Ascension Islands will see the moon occult Mars around 08:00 GMT on Aug. 9.
Tuesday, August 11 at 16:45 GMT — Last Quarter Moon
At its last quarter phase, the moon rises around midnight and remains visible in the southern sky all morning. At this phase, the moon is illuminated on its western side, towards the pre-dawn sun. Last quarter moons are positioned ahead of the Earth in our trip around the sun. About 3½ hours later, Earth will occupy that same location in space. During the following week, the waning moon will complete the last quarter of its orbit around the earth, on the way to new moon. The moonless evening skies between last quarter and new moon are ideal for observing deep sky targets.
Tuesday, August 11-12 overnight — Perseid Meteor Shower Peak
The spectacular Perseid meteor shower, which runs annually between July 17 and Aug. 26, will peak before dawn on Wednesday, Aug. 12. The best time for seeing Perseid meteors starts after midnight, when the shower's radiant is higher in the northeastern sky. Derived from debris dropped by Comet Swift-Tuttle, this is the most popular shower of the year, delivering up to 100 meteors per hour at the peak. Many Perseids are extremely bright, and leave persistent trails. This year, the last quarter moon will be close to the radiant on the peak morning. That will reduce the number of meteors seen before dawn, but should not adversely affect evening meteor-watching.
Thursday, August 13 pre-dawn — Venus at Greatest Angle West of the Sun
On Thursday, Aug. 13, Venus will reach its greatest separation, 46 degrees west of the sun, for its current morning appearance. The very bright, magnitude -4.43 planet will be shining in the eastern sky between 2:45 a.m. local time and dawn. Viewed through a telescope, Venus will show a half-illuminated disk (inset).
Friday, August 14 from 10:30 p.m. EDT — Ganymede's Shadow and the Great Red Spot Cross Jupiter
From time to time, the Great Red Spot (GRS) and the little round, black shadows cast by Jupiter's four Galilean moons become visible in backyard telescopes as they cross (or transit) the planet's disk. Commencing at 10:30 p.m. EDT on Friday evening, Aug. 14 (or 02:30 GMT on Saturday, Aug. 15), observers in the Central Time zone, and east of there, can watch both Ganymede's large shadow and the Great Red Spot travel across Jupiter's northern and southern hemispheres, respectively. The show gets even better after midnight when…
Saturday, August 15 at 4:08 GMT — Rare Double Shadow Transit with GRS on Jupiter
Commencing a few minutes after midnight on Friday, and continuing during the wee hours of Saturday, Aug. 15, observers in the Americas can witness the rare event of a double shadow transit — accompanied by the Great Red Spot! At 12:06 a.m. EDT (or 04:06 GMT) Io's small shadow will join Ganymede's larger shadow and the Great Red Spot already progressing across Jupiter's northern and southern hemispheres, respectively. The trio will remain visible until Ganymede's shadow and the GRS move off Jupiter at about 1:53 a.m. EDT (or 05:53 GMT). Io's shadow will complete its transit at approximately 2:25 a.m. EDT (or 06:25 GMT).
Saturday, August 15 all day — Crescent Moon close to Venus
In the eastern sky for several hours before dawn on Saturday, Aug. 15, the waning crescent moon will be visible just to the upper left (or 3.5 degrees to the celestial north) of the bright planet Venus. The pair, both sitting among the stars forming the feet of Gemini, will fit within the field of view of binoculars (red circle), and will make a nice wide field photograph when composed with interesting landscape. The moon and Venus will not set until 6 a.m. local time on Saturday. Venus is bright enough to see in the daytime, even with unaided eyes. Taking extreme care to avoid the sun, aim your binoculars at the moon and look for Venus' bright point of light below it. Then try seeing Venus without them.
Saturday, August 15 overnight — Uranus Stands Still
On Saturday, Aug. 15, the distant blue-green planet Uranus will cease its eastward motion through the distant stars of southern Aries and commence a retrograde loop that will last until January (red path with labeled dates:times). The magnitude +5.75 planet is visible in binoculars in a dark sky. To help you find it, Uranus will be sitting 11 degrees, or 1.5 binoculars fields, to the south of medium–bright Hamal, Aries' brightest star.
Wednesday, August 19 at 2:42 GMT — New Moon
At its new phase, the moon is travelling between Earth and the sun. Since sunlight is only reaching the far side of the moon, and the moon is in the same region of the sky as the sun, the moon will be completely hidden from view for about a day.
Saturday, August 22 from 6:32 GMT to 8:15 GMT — Rare Double Shadow Transit on Jupiter
From time to time, the little round, black shadows cast by Jupiter's four Galilean moons become visible in backyard telescopes as they cross (or transit) the planet's disk. During the wee hours of Saturday, Aug. 22, observers in the western half of North America can witness a rare double shadow transit. At 1:32 a.m. CDT (or 06:32 GMT) Ganymede's large shadow will join Io's already-transiting smaller shadow. The pair will cross Jupiter together for nearly two hours, until Io's shadow moves off Jupiter at 3:15 a.m. CDT (or 08:15 GMT).
Tuesday, August 25 at 17:58 GMT — First Quarter Moon
After the moon has completed the first quarter of its orbit around Earth, the relative positions of the Earth, sun, and moon cause us to see it half-illuminated — on its eastern side. A first quarter moon always rises around noon and sets around midnight, so it is also visible in the afternoon daytime sky. The evenings surrounding first quarter are the best times to see the lunar terrain when it is dramatically lit by low-angled sunlight.
Friday, August 28 evening — Waxing Moon close to Jupiter
In the southern sky on the evening of Friday, Aug. 28, the waxing gibbous moon will take up a position just two finger widths below (or 2 degrees to the celestial south of) the bright planet Jupiter — with Saturn to their left. Both objects will fit within the field of view of binoculars (red circle). During the night, the diurnal rotation of the sky will lift the moon to Jupiter's left by the time they set at about 2:30 a.m. local time.
Friday, August 28 all night — Ceres at Opposition
On Friday, Aug. 28, the dwarf planet (formerly asteroid) Ceres will reach opposition, its closest approach to Earth for the year. Its path over several months is indicated in red, with dates. On the nights around opposition, Ceres will shine with a peak visual magnitude of 7.2, well within reach of binoculars and backyard telescopes. As a bonus, Ceres will be situated only palm's width above (or 6 degrees to the north of) the bright naked-eye star Fomalhaut. Both objects will easily fit within the field of view of binoculars (red circle). Ceres will already be climbing the southeastern sky after dusk. It will reach its highest elevation, and peak visibility, over the southern horizon after 1 a.m. local time.
Saturday, August 29 evening — Bright Moon Passes Saturn
The moon's monthly visit with the gas giant planets continues on Saturday, Aug. 29. After 24 hours of orbital motion, the moon will hop east to sit a palm's width to the lower left (or 5.5 degrees to the celestial southeast) of Saturn. Both objects will fit within the field of view of binoculars (red circle). During the night, the diurnal rotation of the sky will lift the moon higher than Saturn.
Sunday, August 30 all night — Sinus Iridum's Golden Handle
On Sunday night, Aug. 30, the terminator on the waxing gibbous moon will fall just west of Sinus Iridum, the Bay of Rainbows. The circular 155 mile (249 km) diameter feature is a large impact crater that was flooded by the same basalts that filled the much larger Mare Imbrium to its east — forming a rounded handle-shape on the western edge of that mare. The "Golden Handle" effect is produced by way the slanted sunlight brightly illuminates the eastern side of the prominent Montes Jura mountain range surrounding the bay on the north and west, and by a pair of protruding promontories named Heraclides and Laplace to the south and north, respectively. Sinus Iridum is almost craterless, but hosts a set of northeast-oriented dorsae or "wrinkle ridges" that are revealed at this phase.