Skip Navigation: Avoid going through Home page links and jump straight to content

Comet Hale-Bopp Update



Sky & Telescope News Bulletin
May 2, 1997


Space scientists from NASA and the European Space Agency predict that the ion tail of Comet Hale-Bopp will be particularly susceptible to the solar wind's influence between April 28th and May 15th. They say the blue- colored tail could show brightness changes, kinks, and perhaps moving structures. Also possible are "disconnection events," when the ion tail breaks off from the comet's coma and reforms a few hours later. Scientists have issued this "tail watch" because the comet is now within 10 degrees of the plane of the solar equator. In this region the outflowing solar wind is gusty and the magnetic field irregular. When the plane is crossed on May 3rd, the direction of the interplanetary magnetic field will change. Amateur astronomers are encouraged to monitor the tail's appearance carefully during this period. Interested observers can access the comet watch home page at


Observers are having an interesting time pinning down the current magnitude of Comet Hale-Bopp. Depending on whom you ask, this celebrated comet has faded to anywhere from magnitude 0.0 to 1.0. However, it's still a cinch to spot after sunset; it should be obvious about 20 degrees above the west-northwestern horizon as soon as it gets dark.


Comet Hale-Bopp is still in view this week, though it has shrunken and faded in the last month. Look low in the west-northwest right at the end of twilight. Bring binoculars!


Today Comet Hale-Bopp passes through the Earth's orbital plane, only about 10 million miles outside the January part of our orbit. Too bad we're not there now, to see the comet from 20 times closer than we did a month ago when it was at its best!


This evening the crescent Moon (now plainly visible) is paired with Comet Hale-Bopp. Just as twilight ends, look low in the west-northwest. The comet is about 4 or 5 degrees (about three finger-widths at arm's length) to the Moon's upper right (as seen from North America). They're partway up the horns of Taurus. Try binoculars.

Copyright 1997 Sky Publishing Corporation. S&T's Weekly News Bulletin is provided as a service to the astronomical community by the editors of SKY & TELESCOPE magazine. Widespread electronic distribution is encouraged as long as this paragraph is included. But the text of the bulletin and calendar may not be published in any other form without permission from Sky Publishing (contact S&T's Weekly News Bulletin and "Sky at a Glance" are available via SKY Online on the World Wide Web ( At present they are not available via electronic mailing list. comethome.gif Comet Hale-Bopp Home Page