August can be a spectacular month so far as the night sky is concerned. The giants of the Solar system, Jupiter and Saturn, lie low in the south, above them the Milky Way arches right up over the heavens. We also have one of the main meteor showers of the year, the Perseids, mid month. However this year the display is spoilt by bright moonlight.
The Plough lies north west with the ‘W’ of Cassiopeia at the same height in the north east. The four stars that make the square of Pegasus are becoming more noticeable in the north east and the summer triangle of stars Altair, Deneb and Vega are still very dominant in the summer sky. Arcturus is dropping to the west while Antares is now past its best.
The southern part of the sky is still taken up by the formless Hercules, Ophiuchus and Serpens. Yet more dull constellations are appearing low in the south east; these are Capricornus, and Aquarius, and although both lie in the zodiac there is nothing else to recommend them.
On the night of the 23rd into 24th of the month. A crescent Moon rises around 1am. You will find it below the Pleiades star cluster, and right on the edge of the Hyades star cluster, near the bright star Aldebaran. Watch over the next few hours preferably with binoculars or a small telescope, to see the Moon hide several of the Hyades stars in turn.
Magnificent Jupiter rules the evening sky, appearing low in the southwest in Ophiuchus, above the red giant star Antares. At magnitude –2.3, the giant planet is the brightest object in the night sky after the Moon. It sets below the horizon about midnight.
Saturn lies higher in the sky, to the left in Sagittarius. Setting around 2.30am, the ringworld shines at magnitude +0.2.
Neptune lurks in Aquarius, at a dim magnitude +7.8. It is visible all night long.
Its planetary twin, Uranus at magnitude +5.8, lies in Aries, rising around 10.30pm.
Mercury is putting on the first of two excellent apparitions this year. The other is in November. Look very low in the east between 5 and 6am, to spot this elusive world. It increases in brightness from +1.9 to –1.7 during the course of this month. Mercury will be easiest to spot mid-month when highest in the morning twilight.
Venus and Mars are too close to the Sun to be visible, this month.
The most anticipated meteor shower of the year, the Perseids will peak on the night on August 12/13 when around 80 meteors per hour can be seen, although many meteors will be seen a day either side. This year however, the Moon will spoil the display.
The Perseids are connected with comet Swift-Tuttle which was discovered by Lewis swift and Horrace Tuttle in 1862. The comet takes 133 years to orbit the Sun. However the meteor shower has a very long history.
Phases of the Moon for August :-
New Moon 1st
First Quarter 7th
Full Moon 15th
Last Quarter 23rd
New Moon 30th