Day | Time (UTC) | Event |
|---|---|---|
1 | 14:00 | Mercury at superior conjunction |
2 | 05:24 | Saturn at opposition |
2 | 07:35 | Moon at apogee: 404,410 km (251,89 mi.) |
8 | 13:50 | New Moon |
11 | 07:00 | Venus 4.4°S of Moon |
12-13 | Perseid meteor shower peak | |
15 | 15:20 | First quarter of the Moon |
17 | 09:23 | Moon at perigee: 369,124 km (229,363 mi.) |
19 | 03:03 | Mars 0.1°N of Mercury |
19 | 23:05 | Jupiter at opposition |
20 | 22:19 | Saturn 3.8°N of Moon |
22 | 04:52 | Jupiter 4.1°N of Moon |
22 | 12:02 | Full Moon |
30 | 02:22 | Moon at apogee: 404,100 km (251,096 mi.) |
30 | 07:13 | Last quarter of the Moon |
August 2021
This month we continue to enjoy the summer constellations and the warmer weather, as the nights are getting just a bit longer.
The most significant feature this month is undoubtedly the Perseid meteor shower. Many believe this to be the best shower of the year, as the weather tends to be clear and outdoor temperatures enjoyable. The shower tends to be reasonably consistent with bright fireballs. Though the shower began in July, the peak occurs on the night of August 12 to 13. On most nights, the shower is best at midnight and later, when the constellation Perseus is high in the sky.
Saturn is at opposition on August 2, and Jupiter is at opposition on August 19. They are at their brightest and largest this month – perfect for telescopic observation of satellites, rings, shadow transits, and the Great Red Spot.
On the evenings of August 10 and 11, the crescent Moon will be about 7 degrees away from Venus in the western evening sky, first to the right and then to the left. Another after-sunset treat occurs on August 19, when Mars will be about 1 degree from Mercury very low in the west – a challenging near-horizon observation.
On August 20, Saturn will be about 4 degrees north of the waxing gibbous Moon in the night sky. On the night of August 21, Jupiter will be approximately 5 degrees north of the nearly full Moon.
The Moon is at apogee on August 2, with the new Moon occurring on August 8. The first quarter is on August 15, followed by the full Moon a week later. The Moon will be at perigee on August 17 and then at apogee once again on August 30, which is also the date of the last quarter.
Highlights in the Southern Sky
The constellations Sagittarius (the Archer) and Scorpius (the Scorpion) still dominate the southern sky. Take a look at Sagittarius, and just off the tip of the teapot spout, you’ll find the center of our galaxy, the Milky Way. Below the spout lies Ptolemy’s Cluster (Messier 7), an open cluster of stars.
This is also a great time to enjoy the Sagittarius Star Cloud (Messier 24). This cloud is a great binocular target, and it’s easy to get lost among the stars.
The fantastic part about this time of year is that the Milky Way stretches right across the sky through the constellations Cassiopeia, Cygnus (the Swan), Aquila (the Eagle), and Scutum (the Shield) to Sagittarius. There are so many naked-eye targets, binocular targets, and targets for telescopes of all sizes.
Pegasus (the Winged Horse) is now clear in the east, marked by “the Great Square,” and Delphinus (the Dolphin) can be spotted between Pegasus and Aquila.
The constellation of Scutum can be found just above Sagittarius, and near Scutum’s tip is the Wild Duck Cluster (Messier 11). This open cluster of stars is located roughly 6,200 light-years from Earth and is one of the most densely populated open clusters known, containing approximately 2,900 stars.
The constellation Ophiuchus (the Serpent Bearer) rises above Scorpius, which puts it in a good place to observe the globular cluster Messier 10.
Highlights in the Northern Sky
The constellation Ursa Major (the Great Bear) is now low in the northwest, while Camelopardalis (the Giraffe) lies to the northeast.
Perseus, another constellation, is rising in the northeast with its brightest star Mirfak, which also means that the Double Cluster (NGC 869 and NGC 884) is rising along with it.
Cassiopeia shares the northwestern sky with its familiar “W” shape. But one of the best things to observe is the magnificent Andromeda Galaxy (Messier 31). The Andromeda Galaxy is found easily by following the star Shedar in Cassiopeia to Mirach in the constellation Andromeda and then looking north. Andromeda is visible in moderate- to dark-sky locations as a faint fuzz. A pair of binoculars or a small telescope will reveal the nearest large galaxy to Earth in more detail, particularly the bright central bulge. Andromeda is 2.4 million light-years from Earth, with a diameter of 200,000 light-years. This spiral galaxy is on a collision course with our Milky Way, though that event will likely take place 4.5 billion years from now.
Andromeda also has roughly 20 satellite galaxies; Messier 32 and Messier 110 are the best known.
The star Arcturus is now in the west, with the constellation Hercules above.