NASA's Mars Phoenix landed on the Red Planet's north polar plain on May 25th. As a bonus, Mars is easy to see in the early evening sky right now.
Mars is still fairly high in the west at dusk this month, and you won't want to miss it! It passes in front of an easy-to-see cluster of stars from the 22nd to the 24th. On the 25th, the night Phoenix touches down, Mars will hover just beyond the cluster's western edge.
The cluster is called the Beehive Cluster, or Messier 44. It's a good binocular target and is even visible to the unaided eye from a rural setting or away from city lights. The Beehive Cluster lies about 600 light-years away. By comparison, Mars is 15 light-minutes distant, and our moon is 1 light-second away.
In 1609, Galileo was the first astronomer to observe the Beehive cluster through a telescope. In 1608, he was also the first to spot Mars through a telescope, and in 1610, he first observed phases on the red planet. "I dare not affirm that I was able to observe the phases of Mars," he wrote to a friend. "Nevertheless, if I am not mistaken, I believe that I have seen that it is not perfectly round." Half a century later, Cassini first discovered that Mars had a north polar cap.
This month, observers using a telescope will also be able to see what Galileo saw--that Mars is not perfectly round. Mars will look like a small fuzzy ochre gibbous moon. To see the north pole of Mars, Phoenix's destination, you will need to use a little imagination. Mars, only twice the size of our own moon or half the size of Earth, is now quite far away. It's 275 million kilometers (171 million miles) from Earth right now. To the unaided eye, Mars will look like a ruddy colored star.
Watch as Mars and Saturn draw nearer to each other this month and next. Saturn is higher in the sky and a brilliant view in telescopes.
Last Updated: 24 February 2011