Tuesday, February 24, 2009
By JIM WHITE
It seems that the year has just begun, and we are greeting the month of March. The spring equinox, the Ides of March, and St. Patrick's day, warmer weather, daylight savings, and early spring wildflowers...all here, already.
The night skies herald the month too, as bright winter constellations give way to their relatively dim spring cousins. Orion sinks lower in the west, while Leo the lion and Bootes the herdsman climb in the east. Saturn shines at its brightest in March, and Venus passes from the evening to the morning sky.
As has been the case for a couple of years, Saturn is located in the constellation Leo. The ringed planet takes over 29 years to orbit the Sun, and thus appears in the same area of our sky from one year to the next. On March 8, Saturn will be at "opposition," when it is closest to the Earth. On that day, the Earth will be right between Saturn and the Sun. Therefore, Saturn will be on the "opposite" side of the Earth from the Sun, hence the term. Saturn will rise at sunset, will be at its highest point in the sky at midnight, and will set at sunrise. Saturn's rings will be difficult to pick out this year, as we'll be looking at the ring edges, and they are pretty thin.
The constellation Leo is located along the "ecliptic," the path that planets appear to follow in the sky. Since most of the planets are in about the same orbital plane, they move along this path. In 2012, Mars will be in Leo, followed by Jupiter in 2016. The planets further out take a real long time to orbit the Sun, and visit Leo less often. Look for Uranus to be located in Leo, in 2047 -- if you're around!
A constellation neighbor of Leo's that is on the ecliptic is Cancer, just to Leo's right, between the Lion and the stars Castor and Pollux, the twins of Gemini. The stars of Cancer are dim, but the constellation provides a nice sight if you scan the area with binoculars. You should be able to see a faint cluster of bright stars -- the "Beehive" cluster.
Also known as M44 or the Praesepe, the Beehive is one of the nicest star clusters you can observe with binoculars. See if you can find it. On dark nights, it is faintly visible with the naked eye.
Venus still shines bright in our evening sky in early March. However it will slowly dim, and get lower and lower in the western sky. By the end of the month, it will be lost in the Sun's glare. Take a look low in the east around month's end in the morning, and you'll see that our neighbor has become the "morning star." In April, it will rise higher in the morning sky.
March's Moon will be full on the 11th, and new on the 26th. On March 2, it will pass in front of the Pleiades star cluster, just as it sets late in the evening. It will be located close to the Beehive cluster on March 7, but the bright Moon will "wash out" the nearby star cluster. The Moon will be near Saturn on March 11, and near the bright star Spica on March 13.
Remember that our skies darken an hour later, beginning on March 8, with the advent of daylight savings time. But those later evenings will be warmer, so take advantage of clear nights and enjoy early spring!