From The Old Farmer's Almanac:
Sky Watch: March 2012
Our galaxy, the Milky Way. Credit: NASA
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EmailHere are the monthly sky watchhighlights. Each month, we share the wonders of the universe to help you explore the night sky from your own backyard. (Note: Times listed below are ET.)
March 2012
by Bob Berman, as featured in
The 2012 Old Farmer's Almanac
The 2012 Old Farmer's Almanac
Mercury is brightly visible the first week of the month, low in the west 40 minutes after the sunset. Mars, out all night, reaches opposition on the 3rd and comes closest to Earth on the 5th at magnitude -1.2. At 60 million miles distant, this poor opposition makes Martian details telescopically challenging. Dazzling Venus meets brilliant Jupiter between the 7th and the 18th above the sunset point. Venus’s greatest separation from the Sun is on the 27th. The Moon hovers below Saturn and the blue star Spica on the 10th, spectacularly sits to the right of Jupiter on the 25th and to the left of Venus on the 26th. The equinox arrives at 1:14 A.M. on the 20th to bring the earliest arrival of spring in 116 years.
Sky Map: March 2012
Courtesy of Jeff DeTray. Love astronomy? Visit his site atAstronomyBoy.com
Sky map produced using Chris Marriott's Skymap Pro
Sky map produced using Chris Marriott's Skymap Pro
Astronomer Jeff DeTray has created the printable Sky Mapbelow to help you navigate the night sky. This month's highlight: Dancing with the Planets!
Stars may dance on television, but in the March sky, it is the planets Venus and Jupiter who are partners in a nightly waltz. The pair stay close together, low in the west, for most of March. Jupiter remains pretty much in one place all month, while the position of Venus changes noticeably from night to night. If you venture out every few evenings during March you'll see Venus march steadily past Jupiter until she gradually moves up, up, and away by month's end.
Stately Jupiter is the largest planet in our solar system. How large? Let's compare it to our own Earth. By diameter, Jupiter at 88,865 miles is 11.2 times the size of Earth. By surface area, Jupiter is 122 times the size of the Earth. By mass, Jupiter is 318 times larger than Earth. Finally, by volume, Jupiter is a whopping 1,321 times larger than our home planet. That's right: It would take 1,321 Earths to fill up Jupiter! You might wonder how Jupiter can be 1,321 times the volume of Earth but with a mass that is only 318 times as great. The answer is that Jupiter is comprised largely of gases surrounding a small solid core, whereas our Earth is mostly solid with a dense molten core. Jupiter Trivia: Jupiter has rings, but compared to the renowned rings of Saturn, Jupiter's are dark and dim.
Venus is the goddess of love and beauty. As the brightest of all planets, she certainly deserves her name. Venus is often referred to as Earth's sister because the two planets are so similar in size and composition, with Venus just slightly the smaller of the two. Venus is so bright because she is both highly reflective and relatively close to us. The dense carbon dioxide atmosphere of Venus reflects sunlight extremely well. At its nearest, Venus is closer to us than any other planet ever gets, a mere 25.5 million miles. The combination of reflectivity and proximity makes Venus dazzlingly bright. Venus Trivia: Venus displays phases, just like our Moon. With a small telescope or even large binoculars, you can see the phases quite clearly.
Both Jupiter and Venus have been visited by spacecraft from Earth. More than 20 spacecraft have been sent to Venus, starting with Mariner 2 in 1962. The Soviet Union's Venera 7 became the first space probe to land on another planet when it touched down on Venus in 1970. Jupiter is much more distant and therefore much more difficult for spacecraft to reach. The first to do so was Pioneer 10, which flew by the giant planet in 1970. The Galileo probe orbited Jupiter for eight years beginning in 1995.
Jupiter and Venus aren't the only sights in March sky. Enjoy the bright stars of winter while you can, because they will soon dip below the horizon for the summer. Don't worry— they'll return in the autumn!
Explore the sky night from your own backyard. A printable black and white map is provided below!
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