Starwatch Newsletter Minnesota Starwatch is a tape-recorded message describing the night sky in the Midwest, which can be called by telelphone number (612) 624-2001 It is updated montly, and is produced by the Department of Astronomy, University of Minnesota 116 Church Street SE, Minneapolis, MN 55455

The biggest news this month may be the appearance of a bright comet in the night sky. Discovered on January 30th of this year by a Japanese comet hunter, Comet Hyakutake (HI-ah-KU-tah-key) will pass through the Minnesota sky during March and into April. On March 26th, this comet will pass within 10 million miles of the earth which may make it so close that it will appear as a diffuse cloud covering a large part of the sky centered on the Little Dipper. For charts of where this comet will appear in the Minnesota sky, check out the Astronomy Department Homepage on Comet Hyakutake on the World Wide Web (http://ast1.spa.umn.edu/Outreach/hyakutake.html).

March 20th, of course, marks the Spring Equinox, when the sun reaches the point where it crosses the equator into the northern celestial hemisphere. From now on the days will grow longer as we approach the warmth and light - almost unimaginable to us winter weary observers now - of the Summer Solstice three months away.

March is a good month to observe the Winter Triangle of three bright stars Sirius, Betelgeuse and Procyon. Sirius, also known as the Dog Star, is the brightest and one of the nearest of all stars. This white star, which forms the central point of the constellation Canis Major, is accompanied by a faint white companion star Sirius B. Astronomers didn't realize the existence of Sirius B until the mid-19th century when telescopes became powerful enough to observe the small dense star in the shadow of its bright companion. Sirius B was the first star to be recognized as a White Dwarf. You'll find Sirious and the other of the Winter Triangle in the South about midway above the horizon in the evening sky.

March is also a good month to reflect upon one of the original purposes of the profession of astronomer - as calendar maker. When Julius Caesar was told to beware the Ides of March, the problem referred to wasn't exactly an astronomical one, but it might as well have been. In ancient times, the Roman month was calculated around three significant days - the Calends occurred at the time of the new moon, the Nones at the First Quarter of the Moon, and Ides or midpoint of the month which was supposed to fall on the Full Moon. Unfortunately, Romans also had the practice of interpolating political holidays, without regard to the lunar limitations of their calendar. By the time Julius Caesar came to power in 63 BC the calendar was almost three months out of coordination with the solar year and the seasons. Caesar's response to the calendar problem was a rather modern one. He appointed the Roman equivalent of a Presidential Science Advisor to study the issue. Sosigenes, an Alexandrian astronomer, was charged with the task of coming up with a new calendar. Unlike many a modern government science advisory panel, Sosigenes devised a solution which was actually implemented. The Julian calendar, as Sosigenes' plan was known, divided the year in the 365, twelve month sequence now familiar to Western civilization. The Julian calendar replicated the solar year within 11 minutes and 14 seconds. That 11-plus minute discrepancy eventually forced a further adjustment of the calendar in the year 1582, when the Gregorian calendar was adopted. By then, though, Sosigenes' plan had lasted over 1500 years, a feat which should impress government science advisors everywhere.

The Astronomy Department at the University of Minnesota offers free telescope sessions on Friday nights from 8:00-9:30pm if the sky is more than half clear. You can call ahead at 626-0034 to check whether a session will be held (if no answer, there will be a session that evening). Come to Room 450 of the Physics Building on the East Bank of the Minneapolis campus. Groups of 10 or more require advance reservations.

At the Minneapolis Planetarium, "Follow the Drinking Gourd" is playing Saturdays and Sundays at 1:00pm and 3:30pm. "Black Holes!" is the Thursday evening feature playing at 7:00pm. "Cosmic Critters" is showing on Saturdays at 11:00am and 2:15pm and on Sundays at 2:15pm. Their monthly Skywatch program of current sky information will be held on Monday, March 4th at noon and on Wednesday, March 6th at 7:00pm. The Planetarium is located in the main branch of the Minneapolis Public Library at 300 Nicollet Mall; for further information, please call 372-6644.

The Minnesota Astronomical Society, the local club of amateur astronomers, meets in the auditorium of the Science Museum of Minnesota in St. Paul on Tuesday, March 5th at 7:30pm. To learn about this month's Astronomical Society activities, call their recorded message at 649-4861.

Minnesota Starwatch as well as other public outreach items are now available on-line! The URL address is http://ast1.spa.umn.edu/Outreach/.

This has been Minnesota Starwatch, produced by the University of Minnesota Astronomy Department in cooperation with the WCCO Weather Center.

Last Updated: Tue Apr 21 16:43:06 1998