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(meteorobs) C/1997 O1 (comet Tilbrook)
Hi guys -
Michael Boschat posted this on our RASC net, thought a number of you would
be interested in it as well.... even though it's comet and not meteor
related (in its present passage! ;)
- Cathy
Great White North
>Date: Thu, 24 Jul 1997 15:07:52 -0300
>From: Michael Boschat <andromed@atm.daldot ca>
>X-Sender: andromed@Sleet
>Subject: RASC List: [vsnet-chat 465] C/1997 O1 (comet Tilbrook) (fwd)
---------- Forwarded message ----------
Date: Wed, 23 Jul 1997 20:35:54 -0300
From: Anthony Beresford <starman@CAMTECHdot net.AU>
To: astro@brickbat12.mindspring.com
Subject: [ASTRO] New Comet
The IAU has just announced(circ 6705) that comet 1997O1 is confirmed.
It was noticed by Justin Tilbrook , a member of my local
astronomy club while doing variable star observations, and
confirmed by Gordon Garrard , who captured it on CCD images.
Justin lives in the Clare valley, a wine-growing district some
120 km north of Adelaide.
The comet is moving 3-4 arc minutes an hour , not 4 degrees/hour
It is mag 10 or so, has a 2 arc minute coma and no tail [in 30
second exposure CCD image on a 0.25 f/4 telescope]
Last position from Gordon was(epoch 2000):-
Time UT July 23.46876
RA 12 20 49.36
Dec -18 04 12.9
Tony Beresford
>---------- Forwarded message ----------
>Date: Thu, 24 Jul 1997 14:56:10 -0300
>From: Fraser Farrell <fraserf@dovedot net.au>
>
>G'day all,
>
>I guess IAUC 6705 makes it official, so I'm going to go slightly off-topic here
>in vsnet-chat and mention "comets found while trying to observe variable
stars".
>
>Justin Tilbrook is not on Internet, but any messages can be passed through me.
>Also photos, CCD images, anything that looks impressive when framed and hung on
>the wall for display :)
>
>On Justin's behalf I thank those vsnetters who tried to confirm this comet and
>those who sent congratulations. Don't expect him to call you this month
because
>I think Kathy will kill him when she sees their next phone bill!! <g>
>
>The English word for this observation is "serendipity". Or in Australian
>"strewth what a lucky b....!". Justin does not search for comets. He just
>happened to be looking in the right direction at the right time, and was
>familiar with the starfield. I think Albert Jones (New Zealand) is the only
>other variable star observer to accidentally discover a comet?
>
>This discovery shows (again) the value of checking the starfields around your
>favourite variables. ** Don't just do the estimate! ** Next time it might be
>_your_ name on a comet, nova, or new variable.
>
>For those readers wondering why Bill Bradfield didn't find it first, I can say
>that the sky over Bill (about 40km from me) has been almost solid cloud all
>month. Bill has recovered from his recent surgery and will resume comet
hunting
>as soon as the sky clears.
>
>Because the weather here is still cloudy, I am including this very approximate
>orbit and ephemeris. I know some vsnetters look at comets, so I hope you will
>email me some observations to help improve these numbers. Please....
>
>------------------------------------------------------------------
>C/1997 O1 (Comet Tilbrook)
>Orbital solution from 9 observations Jul 22-23 UT.
>
>Perihelion 1997 Aug 2.2 period 3.37 years
> a 2.250 peri 0.48
> e 0.569 node 303.44
> i 11.833 q 0.97AU
>
>Approximate magnitude 9.5-10.0v. Diameter ~1' arc.
>
>Although these orbital values are about as reliable as a politician's promises,
>I used them to generate positions for the next few days:
> Jul 26.0UT 12h27.3m -15d30.7'
> 27.0 12 30.0 -14 21.1
> 28.0 12 32.9 -13 05.5
> 29.0 12 35.9 -11 43.3
> 30.0 12 39.0 -10 13.6
> 31.0 12 42.4 -08 35.9
>Moving rapidly north into the Virgo galaxies.
>------------------------------------------------------------------
>
>Incidentally, TV Crv was <13.3 on July 22. Justin didn't neglect his _real_
>duties as an observer :)
>
>cheers,
>Fraser Farrell
>
>http://www.dovedot net.au/~fraserf/ email: fraserf@dovedot net.au
>traditional: PO Box 332, Christies Beach, SA 5165, Australia