THE SKY THIS OCTOBER: PROBABILITY OF SHOWERS: 50 PERCENT

Meteors come in three basic types. The first kind are random, isolated events which occur a few times per hour and can be seen on any good, dark, clear night. The second kind are called meteor showers. These are associated with comet debris and happen at regular intervals when the Earth crosses the comet's orbit. During such events, observers can expect several meteors per hour. On the evening of Oct. 8 and again on Nov. 17 and 18 we may get a chance to observe the third kind of meteor activity, the meteor storm. During such events observers can expect to see several dozen meteors per second!

In a traditional meteor shower the dust and debris left over from a comet has had enough time to evenly distribute itself throughout the comet's orbit. Meteor storms occur when the Earth crosses the comet orbit shortly after or before the comet returns on its trek around the Sun. In this situation the debris is still very clumpy and thick in a very small region around the comet. On October the 8th the earth will cross the orbit of comet Giacobini-Zinner which was named after the two astronomers who independently discovered the comet.

This will be the 13th time that the comet has been recorded circling the Sun. This comet was responsible for two of the greatest meteor displays this century in 1933 and again in 1946. While this year's orbital crossing is not quite the same as in 1933 and 1946, there are similarities and we could be in for a big surprise.

Not to be outdone, a more reliable meteor shower will return in November. The Leonid shower (produced from comet Tempel-Tuttle) on the morning of November 17th or 18th might reproduce one of its meteor storms as it did in 1966. The actual storms are brief, perhaps only one or two hours. So keep a look out and call the local radio or TV station to share the news if something spectacular happens.

This month sees the return of the planets Jupiter and Saturn. Jupiter is by far the brightest object in the eastern sky at sundown. Even a small pair of binoculars will reveal the planet and four of its brightest moons. Rising an hour or so after sunset is the fainter planet Saturn. While a pair of binoculars will show an elongated image, it may take a small telescope to resolve the rings. Saturn reaches opposition on the 23rd. It is still best, however, to wait for the planet to be high in the south (midnight) for best viewing.

The center of our galaxy, in Sagittarius, is heading under the horizon in the south, while the Big Dipper is getting very close to the northern horizon. Soon we will have to use other pointer stars in order to find the North Star until the Big Dipper reappears in the spring.

The astronomy club will be hosting a monthly movie night starting this month at 6:30 in room 121 Rhodes hall at the university. This month's feature will be 2010, the sequel to 2001 a Space Odyssey. Under consideration is pizza and/or popcorn during the movie and a lively discussion of space, science and the movie following. Still more future plans call for a field trip to St. Louis science center and planetarium. Our regularly scheduled meetings are the third Monday of the month at 7 p.m. Please join us or call (573) 651-2172 for more information.

Dr. Michael Cobb is chairman of the physics department at Southeast Missouri State University.