Celestial changes

By Dr. Wayne Wooten Pensacola State College
March in this month
By Dr. Wayne Wooten Pensacola State College

March is a month of change – astronomically, chronologically, culturally and spiritually. It is still recognized by many cultures and religions as the beginning of a new year.

In 2011, which began in January, we spring forward to Daylight Savings Time on Sunday, March 13. The Vernal Equinox occurs March 20 at 6:21 p.m.; signaling the Northern Hemisphere’s gradual lean toward the sun and warming weather.

The Full Moon, dubbed Grass Moon, falls on March 19. Because Easter is the Sunday following the Full Moon that follows the Vernal Equinox, this means Easter will fall late in April this year.

While the naked eye, dark adapted by several minutes away from any bright lights, is a wonderful instrument to stare up into deep space, binoculars are better for spotting specific M-81 and M-82 Galaxies. deep sky objects. For a detailed map of northern hemisphere skies, visit the www.skymaps.com web site and download the map for the new month.

March comes in like a Lion, as Leo rises just at sunset. If you take the pointers of the Big Dipper’s bowl to the south, you are guided instead to the head of Leo the Lion rising in the east, looking much like the profile of the famed Sphinx. The bright star at the Lion’s heart is Regulus, the “regal star”.

Jupiter bids us adieu in March, passing into the sun’s glare by month’s end. But on March 15, Mercury and Jupiter appear two degrees apart in western twilight, about 45 minutes after sunset. This is your best chance to see the elusive inner planet this year in the evening sky.

Mercury climbs higher in the sky, leaving Jupiter behind, to reach greatest eastern elongation on March 23, about 18 degrees from the Sun, and setting about an hour after sunset. In March, NASA’s Messenger orbiter enters orbit and should begin an intensive study of Mercury, so by the end of this month, we should have our first global view of Mercury.

By month’s end, Mercury retrogrades between us and the sun, and joins Jupiter in the Sun’s glare. Venus too is heading sunward, moving eastward in the morning sky to vanish in sun’s glare in April for several months. Mars also now is near superior conjunction, behind the Sun.

So who is left?

On April 3, we pass between Saturn and the Sun, so Saturn will rise in the east in Virgo; above the bright star Spica, thus staying up all night. As we are then closest to the ringed wonder, this is the best time to observe the beautiful planet.

When viewed with a telescope, the rings will be even more open than last year, tilted about 11 degrees toward the Earth and Sun. Small scopes will also show its largest moon

Titan. In early April, Saturn will be the only naked eye planet in the sky for several weeks.

To the northeast, look for the bowl of the Big Dipper rising, with the top two stars, the pointers, giving you a line to find Polaris, the Pole Star. Look for Mizar-Alcor, a nice naked eye double star, in the bend of the Big Dipper’s handle, rising by 7 p.m. at the start of March. Above the bowl, in the head of Ursa major, are the colliding galaxies M-81 and M-82, our photo feature for this month, taken by Destin amateur Bob Gaskin with an 8” telescope.

If you follow the handle of the Big Dipper to the south, by 9 p.m. you will be able to “arc to Arcturus”, the brightest star of spring and distinctly orange in color. Arcturus’s color is an indication of its uniqueness. It’s high rate of speed and the direction it’s traveling through the Milky Way suggests it was not formed with our Galaxy.

It’s most likely a recent capture from the Sagittarius Dwarf Galaxy – a smaller satellite galaxy now being assimilated by our huge spiral galaxy. Many of its lost stars, like Arcturus, follow a band across the sky at about a 70-degree angle to our galactic plane.

March goes out like a lamb, not just from Easter tradition, but because Aries the Ram is setting in the west by the end of March. Many of our sayings and traditions have astronomical origins.

For information on the Escambia Amateur Astronomers, visit www.eaaa.net or contact Dr. Wayne Wooten at (850) 484-1152 or wwooten@pensacolastate.edu.