We tend to think of the word "observing" as including a telescope, and indeed it usually does. But this fall there is an observable phenomenon that doesn't require any instrument other than your eyes. Take a look at bright Jupiter and fainter Saturn, just 15o to the east of Jupiter. You're now looking out along the plane of the Solar System. Jupiter lies about 390 million miles from Earth, while Saturn is about 794 million miles. Doesn't that prompt you to visualize our position in the Solar System? If the moon happens to be up, there's another celestial body that by contrast is just a stone's throw away at only 239,000 miles.
The November Leonids
The Leonid Meteor Shower is another celestial event that doesn't require a telescope. These meteors are the residue from Comet 55P/Tempel-Tuttle, which passed through perihelion in February 1998. As the comet moves through the Solar System, there is a long trail of debris left behind that has been "refreshed". On the night of the peak, November 17/18, the Earth's orbit carries it through the path of Tempel-Tuttle, 622.5 days after the comet has been through this area. This shower is renowned for producing meteor storms in the past, and many astronomers expect this year to have potentially good prospects for another storm, although North America will not be in the most favored position. However, unknown perturbations can affect the position of a meteor stream. The best time to observe will be after midnight.
In case it's clear on the night of (Wednesday/Thursday) November 17/18, we're making arrangements to watch the Leonids from the shelter E area at the Lakewood Forest Preserve in Wauconda. Contact Tom Mathieson for details.
Here are some other observing sites: The Northwest Suburban Astronomers has invited us to join them at the Marengo Ridge Nature Center on Route 23, a few miles north of the town of Marengo. The grounds of the Yerkes Observatory in Williams Bay, Wisconsin will be open for those who wish to watch the Leonids. A few LCAS members are also planning to go to the Green River Conservation Area south of Dixon, Illinois to watch for the Leonids and do some general observing. Call Jack Kramer if you have questions about these sites.Published in the November 1999 issue of the NightTimes