Night Sky Watch for May

Written by David Pugh

Dear CDAA Members

This May yet again it continues to be generally rather poor for planets. Mercury, Venus, Jupiter and Uranus are all not visible this month, being either too close to the Sun or in conjunction with the Sun. Mars (mag +1.1) lies very low in Pisces in the eastern pre-dawn sky as it slowly emerges after solar conjunction. If you have a clear eastern horizon your best bet is at the end of May with binoculars before dawn. The beautiful ringed planet Saturn (mag +1.2) is now making steady progress in the pre-dawn sky in Aquarius. However it still lies low in the SE by the end of the month. Distant Neptune (mag +7.9) is currently a very difficult object in Pisces suffering from both pre-dawn twilight and low altitude.

There is a meteor shower during May, the Eta Aquarids peaking in the pre-dawn sky on May 5/6. It comprises debris from Halley's Comet, its radiant lying close to the "Water Jar" asterism in Aquarius. However, whilst the Moon's glare will not be a problem, it achieves an altitude of only some 10 degrees by 4am BST, at the start of twilight. As such it will be best viewed from south of the equator if any of you have a long haul holiday at that time!

By the third week in May we will lose any remaining astronomical darkness until the third week in July. So, if you like hunting down faint "fuzzies", like galaxies, the first part of the month is best for you and the Moon will not be an issue then. The highlighted constellations of the past two months - Ursa Major and Leo, are still well placed for viewing as soon as it gets dark, so do try for some of the objects mentioned then.

This month, or certainly the first half of it, I would suggest trying for galaxies in the Virgo Cluster if you have a telescope. These generally lie some 50 - 60 million light years away and our Local Group of galaxies, including the Milky Way, M31 (Andromeda) and M33 (Triangulum), is an outlying group to this huge super cluster. I suggest that you start at Denebola (Beta Leonis) near the tail of Leo the Lion. If you then move eastwards a few degrees you come to the very heart of the Virgo Cluster, a curving arc of galaxies now called Markarian's Chain. The brightest of these galaxies are M84 and M86, two giant elliptical galaxies. Further to the east in this chain are NGC 4438 and 4435, a pair of interacting galaxies known as "The Eyes". Below and slightly to the east of this chain you will find M87 (mag 8.6). This is a supergiant ellipitical galaxy, one of the largest in the local universe containing several trillion stars, At its heart is an enormous monster black hole of over 6 billion solar masses that astronomers amazingly imaged several years ago.

Further south near the borders with Corvus the Crow you could also try for M104 (mag 8.0) the famous Sombrero galaxy. This giant elliptical galaxy has an unusually large bright central bulge and prominent dust lane. Travelling back north to the faint constellation Coma Berenices ( Berenice's Hair), start firstly at the Coma star cluster (Melotte 111), a nearby open star cluster of some 40 stars faintly visible to the naked eye and a good object for binoculars. Several degrees to the SE you will find NGC 4565 the Needle Galaxy (mag 10.4). This is the best edge on spiral galaxy in the whole sky (size 16 x 2') and is one of my very favourite galaxies. A nice one to end on.

Good Hunting. Looking forward to hopefully seeing you next Thursday evening.

Best Regards