WHAT'S UP
© 2002 Vernon Whetstone

For the week of Sept 16-22

If you can’t tell autumn is coming by the weather, you sure can by looking at the stars. The spring stars are below the horizon just after dark, the summer stars of overhead at sunset and the autumn stars are rising higher in the sky each day. In addition, the winter stars can be seen before sunrise.

In fact, Fomalhaut, the autumn star is now visible high in the southeast at 10 pm MST.

The most prominent object in the night sky right now is the Moon. As I write this on Sunday evening, the Moon is a little past nine days old (from New Moon) and is quite gibbous. It makes a good target for binocular or telescopic viewing. Try to look at some of the larger craters, look for the “central peaks” located in the middle of the craters. If you can catch them with they cross the terminator (the line between dark and light) you can sometimes see them as small, bright specks against the dark background of the crater itself.

You can then follow the light as it makes its way across the crater floor. This kind of observing is best done using larger telescopes.

The weather forecast for the coming week is for clear, moderate evenings when the temperatures will be quite nice for stargazing. Sunday evening was very nice and was still shirtsleeve weather, which means you won’t need a coat or sweater. Too bad the Moon will be getting brighter each evening until it reaches the full stage on Saturday, September 21, at 7:59 am MDT and will be known as the Harvest Moon.

Speaking of autumn, the equinox occurs for us here in the Mountain Time Zone at 10:56 pm on Sunday, September 22. Some calendars show the equinox on Monday, however, since the time of the equinox happens so close to midnight the time zones must be taken into account. The time of the equinox is given as Eastern Daylight Time (EDT), so, 12:56 am Sunday in EDT is 10:56 pm MDT where we live.

Until next time, clear skies and happy viewing.

Information used to prepare this article came from one or more of the following sources: Astronomy Magazine Published by Kalmbach Publishing Co.; August Sky Calendar, published by the Abrams Planetarium; Sky & Telescope's Skyline; Sky Watch by Fred Schaaf; United States Navel Observatory; North American Skies from the Denver Astronomical Society; Star Trak by Hal Kibbey of Indiana University; Earth and Sky on National Public Radio; Distant Suns software by Mike Smithwick; Starry Night Backyard software by Siennasoft; Stargazing for Beginners by John Mosley published by Roxbury Park/Lowell House, 365 Starry Nights by Chet Raymo published by Fireside books and Nightwatch by Terrence Dickinson published by Camden House Publishing; Burnham's Celestial Handbook by Robert Burnham, Jr. published by Dover Publications, Inc., New York.


P.S. Don't forget to get your star chart for September at www.skymaps.com. They are free, and easy to
download and print on your own printer.

Previous What's Up