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From: TerryMoselat signaol.com
Date: 24 October 2007 23:48:24 Oct 2007

Hi all,

This is hard to believe, but I've seen it with my own eyes! I've just
come from an IAA Council meeting (bad timing!), but I saw the comet with
binocs in twilight before the meeting, and easily with the unaided eye
afterwards, from Belfast!  Here's the story......

Comet 17P/Holmes is undergoing a major, spectacular eruption.  The
17th-magnitude comet, which is now at 'opposition', has brightened by a
factor of five hundred thousand or more during the past 24 hours
becoming a naked eye object in the evening sky. This may signify a
break-up of the comet's core or a rich vein of ice suddenly exposed to
sunlight - no one knows. Look for a yellow 2.5th-magnitude
starlike fuzzball in Perseus after sunset. ("2.5th magnitude" means a
little dimmer than the stars of the Big Dipper.) At present the comet
looks more like a star than a comet, because only the nucleus has
brightened - it does not have a discernible tail, but it might grow one
as the outburst continues. 

Tonight it lies close to the star 43 Persei, about 5 degrees East of
Alpha Persei. To locate it, take a line from Alpha Persei to Delta
Persei, then left at 90 degrees to that line for about 2/3 of that
distance - you'll see a bright 'star' that should not be there - that's
the comet!!!!

At midnight tonight (24/25 Oct), it's at RA 03h 52m 57.9"; Dec + 50 deg
08m 10.6".

Tomorrow night (24h) it's at RA 03h 52m 05.0"; Dec + 50deg 12m 34.0"

If you have a computer programme, the elements are:

Epoch: 2007 May 20.0 TT. T = 2007 May 4.4995 TT q = 2.053169 (2000.0) n
= 0.1432508 a = 3.617468 e = 0.432429 i = 19.1132 P = 6.88

(Peri = 24.2585; node = 326.8675)

This is an absolutely amazing outburst, and you should see this object
if at all possible - no-one knows what will happen next.

Clear skies,

Terry Moseley

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Last Revised: 2007 October 25th
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