The Comet is Coming (Maybe)
Mark Pottenger
There is a good chance that we will be able to enjoy a spectacular comet this spring. Comet Austin, discovered as an 11th magnitude object in the constellation Tucana on December 6, 1989 by Rodney R. D. Austin of New Zealand, may be the best comet for viewing since Comet West in 1976. Comet Austin is expected to be a brighter than usual comet because of the distance from the Sun (230 million miles) and Earth at which it was discovered and its magnitude (brightness) when it was discovered. As anyone who remembers the Comet Kohoutek washout knows, predicting the later brightness of a comet based on early observations is iffy, so all early predictions and hopes for Comet Austin could turn out wrong. If the predictions are right, we will be treated to a bright comet well placed for morning sky Northern Hemisphere viewing from mid April through late May.
From perihelion 32 million miles from the Sun on April 9th through closest approach at 23 million miles from Earth on May 25th, Comet Austin will be receding from the Sun and approaching the Earth. It will travel through the constellations of Andromeda, Pegasus, Delphinus and Aquila during this period, and is hoped to be of first or second magnitude through most of the period. The comet will be higher in the sky by the end of morning twilight each day during this time. It is hoped that a tail a dozen or more degrees long will be visible during the period of late April and early May when the Moon's light won't be interfering with viewing. The comet's tail will point at the Great Andromeda Galaxy (M31) on April 19-21, possibly reaching far enough to pass in front of it. The comet passes only 5 degrees from the galaxy on April 24. By the end of April, the comet will be rising around 2 A.M. daylight time. After some interference from the Moon in early to mid May, viewing should again be good starting May 19th. Maximum visible tail length should be some time between May 15 and May 25, with the view of the tail rapidly foreshortening after the 25th because it will be moving almost directly away from us. By the end of May, the comet will rise around 9:30 P.M. daylight time and be high in the sky around 3 A.M. The comet should fade rapidly in June, but should still be easily visible with binoculars when the Moon isn't interfering. It reaches opposition to the Sun on June 7.
If you want to view the comet, get as far from city lights as you can—dark sky is really needed to see comets. For the late April and May viewing period, you want an unobstructed view to the northeast. If it is as bright as is hoped, it will be easily visible with the naked eye, but you might also use binoculars. If you want to look more closely at details, use a telescope. Get the current issue of an astronomy magazine like Sky & Telescope or Astronomy for the most recent predictions and maps of where to look.