Our planetary system may be vast, but at times some of our neighbor planets are easily visible without a telescope. Right now, for example, you can spot Saturn and Mars low in the western sky just after sunset - even if you live under bright city lights.
Presently, Saturn is 1.4 billion kilometers (900 million miles), and Mars is 320 million kilometers (200 million miles) from Earth. However, they appear very close together in the sky right now. Saturn appears as a pale golden glow, and fainter and much smaller Mars appears reddish.
You'll find both Mars and Saturn about 30 degrees above the western horizon on June 10th. To find them, you can use your closed fist at arm's length, which measures about 10 degrees, to locate the planets in the sky. A week later the two planets will be even closer together, when they appear less than one degree apart -- less than the width of your little finger. Through binoculars or a telescope, you can see both planets straddle a faint group of stars known as the Beehive Cluster on June 13. Distant Saturn moves slowly away from the cluster as speedy Mars approaches it. From June 14-16 Mars passes in front of the cluster as shown on the insert, and on the 17th Saturn and Mars will be only 1/2 degree apart to the side of the cluster. A week later Mars will appear to the upper left of Saturn.
Two bonus objects in the western sky present some unique opportunities for the astronomy enthusiast this month. First, toward the end of the month, Mercury will rise out of the glare of sunset, about 10 degrees below Saturn and Mars. Second, faint Vesta, the third largest but brightest asteroid, is near Saturn and Mars this month. This target will require a telescope to see.
After viewing the objects in the western sky, turn around to see the brightest object in the sky right now. That's Jupiter in the southern sky. You can't miss it.
To wrap up the month, look low in the sunset glare on June 27th and 28th to see the crescent moon, and bid a fond farewell to Mars and Saturn for now.
Last Updated: 24 February 2011