brianb
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« on: September 02, 2008, 07:11:01 pm » |
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T Corona Borealis is normally a 10th magnitude star, within easy reach of small telescopes. On two recorded occasions, in 1866 and 1946, it has undergone short nova-like outbursts to mag. 2 and 3.5. I monitor this star; recently it has begun to fluctuate by a few tenths of a magnitude from night to night, and sometimes it can even be seen to be "flickering" on a time scale of seconds. Perhaps this recurrent nova is about to erupt again. Anyway it's worth keeping an eye out for. The field is very easy to find; downloadable charts are available from the British Astronomical Association http://www.britastro.org/vss/xchartcat/t-cr-b_.htmlIf you see this star brighter than mag. 9 please report immediately!
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martinastro
Martin Mc Kenna
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Maghera, N. Ireland
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« Reply #1 on: September 02, 2008, 09:45:32 pm » |
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Thanks for the alert Brian!!. I have been watching that area for years using binoculars and have always wanted to see this star erupt. It brings to mind the frustration Leslie Peltier had when the Nova flared during his hour of slumber. I will pay extra attention to 'T' now. Let's hope it does something interesting....
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brianb
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« Reply #2 on: September 03, 2008, 09:15:14 am » |
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It brings to mind the frustration Leslie Peltier had when the Nova flared during his hour of slumber. Not exactly like an Iridium flare! On past behaviour, T CrB in outburst will be visible to the naked eye for a few days and above mag 9 for ~ 3 weeks, with a subsidiary rise to ~ 8 after 3 months. Worth a look nightly, even with bins to check for no outburst even if you don't bother making a magnitude estimate. BTW R CrB which is (apparently) not to far away is still lurking around mag. 14 - it's been faint for a couple of years now.
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martinastro
Martin Mc Kenna
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« Reply #3 on: September 03, 2008, 11:33:05 pm » |
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martinastro
Martin Mc Kenna
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« Reply #4 on: September 04, 2008, 02:40:05 pm » |
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Ever since Brian's alert I have been monitoring the T Crb field with binos with more intent. Took a couple of shots last night, not deep enough to catch the old Nova but I have the area anyway.
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Roman White
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« Reply #5 on: September 13, 2008, 10:59:45 am » |
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I had just experienced some inconveniences when searching T CrB in my planetarium software (it uses Tycho-2 catalogue). So I decided to put here some designations of this star taken from Simbad: T CrB GSC 02037-01144 TYC 2037-1144-1 CCDM J15595+2555AB HD 143454 NOVA CrB 1946 ; NOVA CrB 1866 HIP 78322 PPM 104498 SAO 84129 Martin, much thanks for those charts in your message!
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« Last Edit: September 13, 2008, 11:04:29 am by Roman White »
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martinastro
Martin Mc Kenna
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Maghera, N. Ireland
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« Reply #7 on: September 18, 2008, 11:14:52 pm » |
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Many thanks for the link Keith. I will keep an eye on it more closely for now on. Wouldn't it be great to see that star erupt!. Fingers crossed.
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brianb
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« Reply #8 on: September 19, 2008, 08:11:59 am » |
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I've been monitoring this star for about 6 years now, and have seen it fluctuate between magnitudes 10.5-10.0, but it could go at anytime!! Indeed. My estimates in the last six months have varied between 10.8 and 9.8, mostly around 10.0 but on a few occasions the star has been obviously "flickering", varying over a range of 0.2 - 0.3 mags with a time scale of tens of seconds.
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brianb
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« Reply #9 on: September 22, 2008, 10:51:42 am » |
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OK, it hasn't blown (AFAIK), but last night it was brighter than I've ever seen it before - 9.7, a little brighter than comparison star L on the BAA VSS charts.
Other interesting activity by old novae / recurrent novae - RS Oph is at 10.5 which is unusually bright for its minimum phase, and GK Per appears to be in minor outburst, having brightened from its usual 13.2 on Sep 06 and 13.0 on Sep 12 to 12.3 & 12.4 on Sep 20 & 21.
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martinastro
Martin Mc Kenna
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Maghera, N. Ireland
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« Reply #10 on: September 24, 2008, 02:58:10 pm » |
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I really hope at least one of those guys erupts in a big way!. Thanks for the updates Brian on those variables.
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