[vsnet-alert 4470] (fwd) SN suspect in NGC 5128

[Taichi Kato <tkato>]

   We have received the following report.  Could someone check?
  (Any relation with the previously reported suspected object, =NGC5128 V17?)

From: "Cris Ellis" <mrktg@acromet.com.au>
Date: Mon, 27 Mar 2000 13:38:34 +1000
Subject: Suspect SN

On Friday 10 March 2000, at 9.38pm Eastern Australian Summertime I =
observed a potential SN from our Societies dark sky viewing site located =
to the East of Melbourne, Australia.

The object observed was a singularly outstanding star that I have not =
seen before and is massively brighter than any other star in the host =
galaxy. The suspect SN lies within NGC5128, the Centaurus A galaxy, =
which lies 14 Million light years distant. The star was massively =
brighter than any individual star in the galaxy, and was found in the =
north east corner of the galaxy through the telescope eyepiece (upside =
down through the eyepiece of course).

Centaurus A is well known by myself, as it is a uniform galaxy of stars =
of which no single star is individually outstandingly visible in the =
eyepiece, and the sight of this massively brightened object was =
obviously a surprise to myself. I requested the Vice- President of the =
Society Andrew Thorne to view the object, and he confirmed that it could =
be a SN. He is able to place witness of the details of this email =
transmission.

As both Andrew and myself are long experienced observers, we understand =
what galaxies look like, and are well versed with many of same in the =
eyepiece. This object within Centaurus A was a welcomed surprise to us =
as no member of our society has viewed a SN without knowing that it was =
already in existence.

I apologise for the delay in reporting this object, however have been on =
a business trip and have just returned to Melbourne. Andrew Thorne is =
able to corroborate the evidence of the finding and it=92s date & time =
should you require this additional step to be taken.

I am unable to take the step of photographically recording this event as =
I do not have equipment at my disposal to actualise this step. You will =
appreciate that I am a visual amateur astronomer, and a very serious one =
at that.

Notes on observation: The suspect object appeared clearly to lie within =
the galaxy, with brightening directly conducive to it=92s being a SN. =
The telescope used for observation is an eighteen month old 12.5 inch =
f5.3 1/20 wave Newtonian Dobsonian unit. It is an outstanding telescope =
which I constructed personally by hand. Maximum performance of the =
object was gained with a Takahashi 7.5mm ocular which gave approximately =
250 magnifications.

The star halo of the north and south hemispheres of the elliptical =
galaxy are easily cut by the dust lane of the spiral galaxy that is in =
collision in the stellar object. As Centaurus A is a galactic collision =
of a elliptical & spiral galaxy as I am sure you are aware. The suspect =
SN is located to the lower left portion of the galaxy, well away from =
the collision zone where as David Malin and others photographs indicate =
such extreme stellar birth.

Indeed we checked a photograh by Malin at site in a book at the time of =
viewing in order to check our findings which gave us considerable =
enthusiasm as there lies no bright object at that location on the =
wonderful AAT photograph that Malin took.

I wish to firstly enquire for this to be confirmed as a SN, and secondly =
request whether it has been previously claimed as discovered by other =
astronomers. If my record of this is the first then I would like to =
place personal claim on this object as discoverer.

Thanking you in anticipation of your most valued assistance in this =
matter.

Rgds,

Cris Ellis

President

Astronomical Society of Melbourne Inc

Melbourne,

Australia.

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