March 2010
The sky at night can be enjoyed by anyone, even without any optical aids. Just using your naked eyes to scan the constellations, admire the band of stars that is the Galaxy’s spiral arm, notice star clusters, and pick out planets. Viewing from a dark site makes the experience even more enjoyable with much more of the universe layed out in front of you. It is well worth the effort to get far away from the dreaded light pollution and to a really dark site.
You will have noticed the days gradually starting to lengthen. The long hours of night sky observing you’ve enjoyed over the past month or so are slowly getting shorter, and our clocks go forward one hour (UK) on Sunday 28th of March for the official start of summer time.
New Moon/Moonless nights for March, 10th, 11th, 12th, 13th, 14th, 15th, 16th and 17th.
The constellations of winter such as the mighty Orion, Taurus, Gemini, and Auriga will be gradually sinking in the western sky and taking their deep sky wonders with them. But as the winter constellations are starting to make their way out of optimal viewing, more treasures are coming up in the east to take their place.
Good target constellations on the rise are Leo, Virgo, Canes Venatici, and Coma Berenices. This is an area of night sky liberally sprinkled with spiral and elliptical galaxies, including of course the famous Virgo Cluster.
The Virgo Cluster
Ursa Major is virtually directly over head throughout March, for perfect viewing of it’s deep sky objects high up and far away from sky glow. So if you look straight up at around midnight on any night in March you will see the constellation of Ursa Major with it’s unmistakable shape, often called the “Big Dipper” or the “Plough”.
A galaxy in Ursa Major that might benefit from being directly over head as it requires very dark skies is M101, The Pinwheel Galaxy (NGC 5457) RA 14:03 13, DEC 54:20 57. Get to as dark a site as possible and aim your telescope at this magnitude 8.3 face on spiral, 27 million light years away, and a giant at nearly double the size of the Milky way. Although with this galaxy a larger telescope will be needed to spot any glimpses of it’s spiral arms, as a smaller instrument will normally only pick out the bright core. To find it manually and to get you in the area, just look at the first two stars on the handle of the Plough, or Big Dipper and the Pinwheel Galaxy lies above them to form the shape of an equilatoral triangle…
Check out the Beehive Cluster (M44) NGC 2632 in Cancer, RA 08:40 1, DEC 19:59. An attractive open cluster that you might see with the naked eye from a darker location. It’s easy to find this month, just look to the southern sky, The Beehive Cluster is to the lower left of Mars. This is an attractive collection of stars 577 light years away at magnitiude 3.1, and as with many open clusters it looks best in low power. This cluster contains white dwarfs and red giants, and binoculars are perfect for this one.
While you’re in Cancer take your field of view downwards 8 degrees and slightly to the left to locate the star that marks the western point of the upside down “Y” shape of Cancer. To the right of this star you will see the open cluster M67 (NGC 2682) RA 08:50 4, DEC 11:49. This cluster is around 4 billion years old and one of the oldest clusters known. It is a nice object of around 500 stars, including 100 Sun like stars and red giants. This magnitude 6.1 object looks good in low power, but larger scopes will start to resolve this cluster’s stellar population.
Open cluster M67
Why not try a globular cluster, M3 in Canes Venatici (NGC 5272) RA 13:42 11, DEC 28:22 31. It is a bright ball of half a million stars, at 33,900 light years away. This 8 billion years old cluster is one of the largest and brightest globulars, and if you are at a dark site you just might see it with your naked eyes. It covers an area half the size of the full Moon and is dense, with a magnitude of 6.2 it can be seen well in a small telescope. It is kind of out on it’s own with not many objects nearby and lies halfway between two bright stars. Find the brightest star in the constellation Bootes called Arcturus, the handle of the Big Dipper points to Bootes. Now find the constellation Canes Venatici, it’s a tiny constellation below Ursa Major. The brightest star in Canes Venatici is Cor Caroli, M3 lies half way between Arcturus and Cor Caroli.
Globular cluster M3
The Solar System
The main planets on view in March are Saturn and Mars. Saturn reaches full opposition on the 22nd of the month with an angular size of 19″ and a magnitude of 0.16. The rings are only very slightly tilted to us, being nearly edge on, so they present a challenge at the moment.
Mars is very well placed for viewing and should not be missed, although it is slowly decreasing in manitude after reaching full opposition at the end of January.
Venus is gradually making it’s way up from the horizon a bit more as each night passes, you will see it setting in the west after dusk.
“What planets are on show, where to find them, highest points, rising and setting times, magnitudes, and angular sizes are available here…updated every day“
Other things you may want to look out for
If you glance over to the western horizon at dusk on both the 16th and 17th of March, you’ll see Venus near an extremely thin crescent Moon.
On March the 20th watch the waxing crescent Moon get very close to the Pleiades Cluster in the west. As the Moon get lower and lower in the sky it covers more of this large open cluster.
…have a great month’s observing in March !