[vsolj-alert 31] (fwd) Brightening of variable in front of NGC 5128 (=N5128V0017)

[Taichi Kato <tkato@kusastro.kyoto-u.ac.jp>]

(fwd) Brightening of variable in front of NGC 5128 (=N5128V0017)

　ＮＧＣ５１２８（＝ＣｅｎＡ）の領域に明るい変光天体が報告されています。
　１９９６年にも同じ天体と思われるものが明るくなったことが報告されており、
　長周期の矮新星などが考えられますが、現段階では超新星の可能性も捨てきれ
　ません。確認観測が望まれます。

From owner-vsnet-obs@kusastro.kyoto-u.ac.jp Sat Jan 31 16:57 JST 1998
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Date: Sat, 31 Jan 1998 15:51:03 +0930
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G'day all,

Another brightening of the variable star in front of NGC 5128
(Centaurus A):

1998 Jan 26 15:46UT    mag 12.1
1998 Jan 30 16:24UT    mag 10.3
Chart & sequence from Supernova Search Charts (Thompson & Bryant).


Additional information:

A previous brightening to mag 10.5 was detected on 1996 Feb 24.  That
event lasted for several days and was mistaken for a supernova by many
observers (including me!)  A genuine SNI would peak at ~10.0.

The star's position is 13h25.5m -43d02' (2000); which is ~80" south of
the centre of NGC 5128 and well inside the visible body of this galaxy.
It is shown as a 12th mag star on the Thompson & Bryant chart.

The GCVS volume 5 lists a suspected variable at 13h22m26s -42d45'16"
(1950) with a maximum of 12.2V.  GUIDE 6.0 shows no asteroids brighter
than 15th mag within a degree of NGC 5128.

I suspect this star may be a dwarf nova (or novalike var) of long
period.  Further observations (current and historical) are encouraged.


cheers,
Fraser Farrell

http://vsnet.dove.net.au/~fraserf/  email: fraserf@dove.net.au
traditional: PO Box 332, Christies Beach, SA 5165, Australia

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