Minnesota Starwatch

University of Minnesota

Department of Astronomy

Minnesota Starwatch for October 2004
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Starwatch Newsletter

Minnesota Starwatch is a newsletter describing the night sky in the Midwest.

It is updated monthly, and is produced by the
Department of Astronomy, University of Minnesota
116 Church Street SE, Minneapolis, MN 55455

Minnesota Starwatch for October 2004

Hello, this is Minnesota Starwatch for October 2004.

October starts just days after the full moon on September 28, which, as the full moon closest to the official start of Fall, is known as the Harvest moon. Thus, this month starts with the moon waning and last quarter moon is on the 6th. This is followed by new moon on the 13th, first quarter moon on the 20th, and a full moon on the 27th.

During the full moon on October 27th, weather permitting, Minnesotans will be able to observe a beautiful lunar eclipse. This lunar eclipse is wonderfully timed as it starts in the early evening and is completely done in time to get a good night's sleep. Specifically, the moon first enters the penumbra at 7:06pm DST. The penumbra is the fringe of the earth's shadow, and the moon will start to get dimmer until it enters the umbra, the dark core of the shadow, at 8:14pm. At this point you can see the earth's shadow start to slide across the face of the moon. At 9:23 pm, the moon will be entirely inside the umbra, and thus the total eclipse begins. The total eclipse lasts for an hour and 20 minutes. During the total eclipse, you will still be able to see the moon (weather permitting) because light from the sun that is bent by the earth's atmosphere leaks into the umbra and dimly illuminates the moon. The moon should appear reddish in color. The show begins to end at 10:45pm when the moon starts to re-enter the penumbra, and leaves the umbra completely at 11:54. The moon leaves the penumbra completely at 1:03am and is fully illuminated again.

The eclipse will be visible by the entire western hemisphere, so you can share this experience with your South American friends. One of the fun things to watch for during the entering and exiting phases is the passage of the shadow edge over various craters. A decent pair of binoculars will provide an excellent show.

And where are the bright planets this month? Early risers have the opportunity to view three bright planets this month.

If you're up early on October mornings, Venus can be observed as the bright object in the east up to three hours before sunrise. On the morning of the 3rd you can see Venus and the bright blue star Regulus appear closer together than the diameter of the moon. Saturn rises after midnight this month, and will be the bright object in the southern sky at dawn. Jupiter lies between the Sun and Venus, and thus rises after Venus and before the Sun. As the month progresses, Jupiter and Venus come closer together, and next month's starwatch will be reporting on a very close passage on November 4th. A crescent moon passes close to Jupiter on the 12th.

If this is not enough to satisfy you for October, then be prepared to get up early between October 20th and 26th to watch for shooting stars from the Orionid meteor shower. Meteor showers are always best observed after midnight, but this year the lunar phase makes that even more true as the moon transitions from first quarter to full moon and will be setting in the early morning. The official peak is on the 21st, but with peak counts of 15 meteors per hour, the Orionids are not the most exciting of our meteor showers.

For fun Astronomy Outreach programs check out our Public Outreach link, or if you're interested in how you can help build the new Minnesota Planetarium, please call 612-630-6151 or visit http://www.mplanetarium.org.

Como Planetarium is offering fun family shows about astronomy on a limited basis; please call 651-293-5398 for more info!

This has been a Minnesota Starwatch produced by the University of Minnesota Astronomy Department.