Last modified: Monday, March 2, 2009
Public star count scheduled in March
FOR IMMEDIATE RELEASE
March 2, 2009
BLOOMINGTON, Ind. -- A major goal of the International Year of Astronomy is to educate people about light pollution, and a good way to do that is through an event called the Globe at Night star count. Now in its fourth year, this project has drawn thousands of participants worldwide. This year's count will run from March 16 to March 28 (http://www.globe.gov/GaN). The idea is to get the public excited about what can be seen in the night sky -- but to emphasize that many of these celestial sights are being lost to light pollution. See http://www.astronomy2009.org/globalprojects/cornerstones/darkskiesawareness/ for more information.
Saturn will be opposite the sun in our sky on March 8, when it will be closest to Earth in its orbit as it rises in the east at sunset and sets in the west at dawn. Saturn will be easily visible almost all night during March as it crosses the southern sky, glowing bright yellow among the stars of the constellation Leo the Lion. Saturn will outshine Leo's brightest star, Regulus, nearby to the right (west) of the planet.
Saturn has at least 60 moons, and the largest one, the planet-sized Titan, can be seen with any telescope. For the best telescopic views, wait until Saturn is at least a third of the way up the sky, above most of the turbulence near the horizon. See http://saturn.jpl.nasa.gov/home/index.cfm for the latest news and images from the Cassini spacecraft orbiting Saturn.
Venus will be high above the western horizon at the start of the month, a beautiful "evening star" as it has been since December. But during the next few weeks Venus will seem to drop out of the sky with startling speed. On March 27 it will pass almost between Earth and the sun, but viewers in the Northern Hemisphere will be able to see Venus both at dusk (near the western horizon) and at dawn (near the eastern horizon). Only every eight years, when Venus passes far enough north of the sun, can we see the planet at dawn and dusk on the same day.
Jupiter will be very low in the southeast a half hour before sunrise at the beginning of March. By month's end it will be about twice as high. Jupiter's size and brightness will make it easy to spot unless it is blocked by a tree or building.
To Jupiter's lower left will be Mars and Mercury. These two planets will be extremely close in the first few days of the month, but they will be so near the east-southeastern horizon that most observers at mid-northern latitudes will be unable to see them. Viewers farther south will have a better opportunity, but they may need binoculars in the brightening sky. Within just a few days, Mercury will disappear into the glow of morning twilight.
The new Comet Lulin will recede from Earth quickly during March, after making its closest approach last month. The fading blob of light will be well placed in the southeast during the evening and may be visible in binoculars. It will pass close to the Beehive star cluster on March 4.
The sun will cross the celestial equator (an extension of Earth's equator onto the sky) on March 20 at 7:44 a.m. EDT (11:44 Universal Time) heading north. This will mark the start of spring in the Northern Hemisphere and fall in the Southern Hemisphere. For the next six months in the Northern Hemisphere, the days will be longer than the nights.
Day and night are not precisely the same length at the time of the equinox. That happens on different dates for different latitudes. At higher latitudes in the Northern Hemisphere, the date of equal day and night occurs before the March equinox. In the Southern Hemisphere, this happens after the March equinox. Information about the exact time of the equinox at different places on Earth's surface is provided at http://aa.usno.navy.mil/faq/docs/equinoxes.php.
The moon will be at first quarter on March 4, full on March 10, at third quarter on March 18 and new on March 26.