From: TerryMosel@aol.com Date: Sat, 16 Nov 2002 21:13:50 EST Subject: LEONIDS - STORM? Hi all, Don't forget that the traditional Leonid maximum is forecast for this Sunday (17th) evening. Rates may have started to drop a little by the time the radiant gets high enough for good viewing (after midnight for most of us), but there should still be some reasonable activity, in spite of the moonlight, say from about 01.00 to dawn. Then there's the first of the predicted additional 'storms' on Tuesday morning (we won't see the second one from GB or Ireland, as it will be at 10.00, in our daylight). Asher & McNaught, and other workers, predict a high sharp peak around 03.55 on Tuesday morning, 19 November. The predicted rates vary from a ZHR of around 1,000 up to about 5,000, or higher. But remember that (1) the actual rates are very hard to predict accurately (whereas the time should be correct to within about 15 minutes or better), and (2) we won't see rates equal to the ZHR! This stands for 'Zenithal Hourly Rate', and it is the number of meteors which would be seen per hour by AN EXPERIENCED OBSERVER, in a TOTALLY DARK SKY (LM = 6m.5), and with the RADIANT IN THE ZENITH. For all of us, two of those three won't apply: because of the moonlight we may see only about 1/3 of the ZHR, and the radiant never reaches the zenith from Ireland, although it will be quite high up at the time of the predicted maximum. So don't expect a 'snowstorm' of meteors. But we might see dozens per minute for a short period, centred around 03.55 on Tuesday morning. If you can't observe from radiant-rise (say around midnight) until dawn, concentrate on the period from 03.00 to 05.00, or if even that's too much, from 03.30 to 04.30. The radiant lies in the 'Sickle of Leo', about a palm-span left of brilliant Jupiter, in the SE sky. Most meteors can be seen when you look about 45 degrees away from the radiant, and about 50 degrees above the horizon - but look anywhere in the sky, at whatever part is darkest, i.e. away from artificial lights and the moon. This is the last chance in our lifetimes to see a Leonid meteor storm from Ireland/GB, so give it your best shot! If you are clouded out, you might like to find out what's happening elsewhere, so check out this site, which will be giving live coverage from around the world: "NASA TV kicks off live coverage of the 2002 Leonid meteor storm on Monday evening, Nov. 18th. The broadcast will feature live reports from meteor watchers around the world, a toll-free telephone number for members of the public, and weird meteor sounds. FULL STORY at The Leonids TV Show -http://science.nasa.gov/headlines/y2002/16nov_leonidstv.htm BTW, Yours truly will be doing a radio interview (barring other major breaking news) on Downtown Radio on Sunday (17th) afternoon, between 2 p.m. and 3 p.m., on the Leonid prospects, but you probably won't learn anything you don't already know. Good Luck, and Clear Skies! Let me know how you fare! Terry Moseley
| Last Revised: 2002 November 18th WWW contact: webmaster@star.arm.ac.uk |
Go to HOME Page  |