Last modified: Tuesday, September 30, 2003
STAR TRAK/October 2003
Mars and Orionid meteors adorn October skies
Mars will still be a dazzling sight during the first two weeks of October, appearing bright orange in the southeast as darkness falls and crossing the southern sky for everyone to see. Enjoy the show while you can, for the red planet's size and brightness will decrease rapidly during the last part of the month as Earth pulls away from it in our faster orbit.
Mars will also serve this month as a brilliant marker for Uranus, one of the huge gas planets so far from the sun that they are usually hard to find without a telescope. Uranus will appear in the same field of view as Mars in 7x50 binoculars. Look to the upper right (north and slightly west) of Mars to find Uranus, though its pale blue-green color may only appear in telescopes. To see a map of the sky showing the two planets, go to http://www.astronomy.com and click on "The Sky Online."
As Mars is descending in the southwest in the early morning hours, bright yellow Saturn will rise in the east along with Castor and Pollux, the two bright stars in the constellation Gemini the Twins. Almost any telescope will show Saturn's rings, tilted toward Earth.
Soon after Mars sets in the west, Jupiter will rise in the east. When Mars begins to fade during the second half of the month, Jupiter will recapture from Mars its status as the second-brightest planet in the sky after Venus.
Mercury will be visible well below Jupiter before dawn during the first week of October. After that, the little planet will quickly sink into the glow of sunrise and remain out of sight for the rest of the month.
Venus will emerge from behind the sun into the evening sky during October, but just barely. At sunset it will be very low in the west-southwest and dropping fast, so it may be hard to spot even with binoculars in the twilight glare.
Locations of current auroral activity can be seen at http://www.sec.noaa.gov/pmap/. Click on "Aurora Viewing" for tips on when an aurora may be visible in your area. Information about solar and other space "weather" is available at http://www.spacew.com/. Aurora sightings are reported at http://www.spacew.com/www/aurora.html.
To watch for auroras when they are most likely to happen, sign up for solar activity alerts by e-mail at http://skyandtelescope.com/observing/proamcollab/astroalert/default.asp.
The Orionid meteor shower will peak on the night of Oct. 21-22. The moon will be a thin crescent and won't even appear until 4 a.m. local time, so observers with a clear dark sky can expect to see about 10 meteors per hour after midnight. The Orionids take their name from the familiar constellation Orion the Hunter, which is where they appear to originate. Orion will rise before midnight in the east-southeast, and the number of meteors will increase as Orion gets farther above the horizon. The meteors are dust particles from Halley's Comet, left behind in the comet's orbit. As Earth crosses Halley's orbit, the particles collide with our atmosphere at high speed and are burned up in an instant by friction with air molecules, creating bright streaks in the sky.
The moon will be at first quarter on Oct. 2, full on Oct. 10 (traditionally called the Hunter's Moon), at third quarter on Oct. 18 and new on Oct. 25.