| March 2004 | |
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 Download this month's star chart! |
A Parade of Planets
Anyone outside on a clear evening shortly after sunset in the last few months has probably noticed a VERY bright star hanging in the western sky. As the weeks passed, it appeared higher and brighter. However, if you were to make a wish on this first star you see tonight, the wish won't come true. You just wished on a planet.
The word "planet" comes from the Greek word for "wandering star" because the planets appear to wander against the background of fixed stars. To avoid confusion, a good rule to remember is that usually stars twinkle; planets don't. If you see a steady, star-like object that is not twinkling or moving, it's probably a planet. In this case, you have been mesmerized by the planet Venus.
While Venus screams for your attention, Mars does not. It appears as a pale orange dot a short distance above Venus. Mars was spectacular last August. Since then, Earth has pulled away, and the distance between the planets has increased significantly. The most exciting thing about Mars right now is the wealth of information coming from the twin rovers Spirit and Opportunity and the three orbiters: Express, Odyssey, and Global Surveyor.
Looking high in the south and eastward, the brilliant stars of winter still dominate the sky. Mighty Orion is easy to locate and serves as a guide to nearby constellations. Start at Rigel, Orion's brighter foot, and draw a line across his body through Betelgeuse, in the opposite shoulder. Follow that line up toward the northeast until you reach a pair of stars of about the same brightness. These two stars, Castor and Pollux, mark the heads of the Gemini twins.
Nestled amongst the legs of Gemini, like a cat demanding to be fed, is another "wandering star", Saturn. When observed through binoculars, Saturn does not show a circular disk like the other planets. It will look like an oval or an egg. This is because average binoculars are not able to separate the rings from the disk of the planet itself.
Farther eastward, just below Leo the Lion, lies Jupiter. Binoculars can reveal as many as four of Jupiter's largest moons in addition to the planet itself. From night to night, the tiny dots adjacent to the planet will change position as they orbit their parent body.
As if four planets in the evening sky wasn't enough, Mercury will enter the scene during the last week of March. While it is fairly small and never appears far from the Sun, Mercury can be surprisingly bright. Look for it below Venus about 30 minutes after sunset. Scanning with binoculars first makes it easier to spot with the unaided eye.
"Wandering Star" Party
To get a closer look at all these planets, join us at the next FREE public observing session at the model airplane field at Edwin Warner Park on Saturday, March 27 from 6:30 to 9:00 PM. Members of the Barnard-Seyfert Astronomical Society (BSAS) will have telescopes available for viewing Mercury, Venus, Mars, Jupiter, Saturn, a pretty crescent Moon, and other celestial sights.
Plan to arrive early to catch Mercury because it will drop below the horizon around 7 PM. Bring binoculars, if you have them, to learn and practice "binocular astronomy". Spring evenings can still be COLD, so be sure to dress warmly. Make reservations by calling the Warner Park Nature Center at 615-352-6299.
Achtung! Astronomy Day!
Madgeburg Hemispheres Experiment Reenactment
Astronomy Day, April 24, 2004, promises to be a unique and exciting day at Adventure Science Center. On that date, representatives from Magdeburg, Germany, will reenact Otto von Guericke's historic hemisphere experiment.
Way back in 1657, von Guericke demonstrated the tremendous force of atmospheric pressure by placing two large hemispheres together, evacuating the air from inside, and hitching a team of horses to each hemisphere. The horses were unable to pull the hemispheres apart. In fact, it took four teams straining on each side to break the vacuum seal.
This dramatic reenactment will celebrate Nashville's strong tie to its sister city of Magdeburg. Throughout the day other activities will highlight current events in astronomy, the Barnard-Seyfert Astronomical Society and the importance of von Guericke's discoveries. Mark your calendar now. Details will be posted on our website by April 1.