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From: TerryMoselat signaol.com
Date: 17 February 2007 21:06:12 GMT
Subject: Wonderful Mira, Lecture, Moon occults Pleiades, ECLIPSE

Hi all,

'Mira' means 'the Wonderful', and now we can see why. This star, the prototype of the Mira class, 
also known as Long Period Variables, is exceptionally bright at the moment. Tonight I estimated 
it as between magnitude 2.0 and 2.1 - about as bright as Polaris! Its average brightness at 
maximum is about 3.4, and it's rare for it to get brighter than mag 2.5. In fact, this is the 
brightest I have ever seen it in 42 years of observing! And maximum is not actually expected 
until 14 March! - although that prediction is not precise.
    At minimum, it can get down almost to 10th magnitude. Its average period from maximum to 
maximum is 332 days.
    As soon as the sky gets reasonably dark, compare it with other stars at about the same 
altitude above the horizon. There are none nearby, but you can use Beta Eridani, 
mag 2.76E(near Rigel); Gamma Eridani, mag 2.90; Kappa Orionis (Saiph), mag 2.05; Alpha Ceti, 
mag 2.50; Gamma Peg, 2.83; Alpha Peg, 2.45; Alpha And, 2.04.
2. A reminder that the next IAA public lecture will be on Wednesday 21st February, by 
Prof Tom Millar, Dean of the Faculty of Engineering & Physical Sciences, and Professor of 
Astrophysics, at QUB. Prof Millar's topic will be "Molecules in Space - the origin of life?"
    It will be held in Lecture Theatre 5, Stranmillis College, Stranmillis Road, Belfast, 
at 7.30 p.m. Admission is free, including light refreshments, and all are welcome.
Note your diaries, and get your cameras and videocams ready: On the evening of 23 February, 
the 45% illuminated Moon will occult the N part of the famous Pleiades Star Cluster. Altogether, 
22 stars above 9th magnitude will be occulted for observers in Ireland that evening, although 
not all are members of the cluster.
    The following information applies to Belfast: observers further South will see the Moon 
pass slightly further to the North, and a few of these stars will not be occulted as seen 
from e.g. Cork. Also, the times of the events will differ for observers in different locations 
- these times are just to give you a guide. Stars are known by different designations - 
don't worry if your PC programme or Atlas shows some of them with other Catalogue numbers
STAR               Mag           Time
V 624 Tau          8.2          E22.10
V 1187 Tau         8.3          E22.23
TYC 1803-188     E 8.1          E22.29
16 Tau             5.5           22.44
19 Tau             4.3           22.50
TYC 1799-306     E 8.5          E22.57
TYC 1803-104     E 8.9          E22.59
TYC 1799-184     E 7.2          E23.05
20 Tau             3.9           23.08
21 Tau             5.7           23.09
22 Tau             6.4           23.12
TYC 1804-2081      6.8           23.35
TYC 1800-1908      7.3           23.44E 'Graze' at Belfast
TYC 1804-1961      7.7           23.46
TYC 1804-2051      8.7           23.50
V534 Tau           8.3           00.06  'Graze' at Belfast
TYC 1800-1622      6.8           00.09  'Graze' at Belfast
TYC 1800-1546      8.2           00.24  'Graze' at Belfast
TYC 1800-1601      6.9           00.26  'Graze' to S of Belfast
SAO 76234          7.5           00.39
SAO 76236          6.6           00.44
TYC 1804-163       7.4           01.01
A 'Graze' means that the Moon's N or S limb just 'touches' the apparent position of the star, so 
the times will vary considerable depending on your location, and if you are on the 'wrong' side 
of the line you'll just see a near miss.
   Good quality video recording, with very accurate timing, can provide useful information on 
the shape and motion of the Moon. Contact Tolis Christou at Armagh Observatory 
aacat signarm.ac.uk if you have such equipment and 
are prepared to make the effort to do some proper accurate observing.
  But for 'casual' observing, even a pair of tripod-mounted binoculars will do for the brighter 
stars, and even the Good Ol' Lidl 70mm refractor will be fine for all the rest!
There will be an excellent Total Lunar Eclipse on the evening of Sat 3 March, all of which will 
be visible from Ireland, clouds permitting. The IAA will be holding a public eclipse-watch at 
the lower car park at Cultra, Co Down, with telescopes and binoculars to view not just the 
eclipse, but the beautiful planet Saturn which will lie not too far away, also in Leo. And maybe 
some fainter Deep Sky Objects while the Moon's light is hidden.
  More details later, but keep that evening free!
Clear Skies,
Terry Moseley


Last Revised: 2007 February 19th
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