[vsnet-chat 2590] CGCS 1045 Addendum

[JG <jgts@jgws.totalserve.co.uk>]

Dear VSNET-Chatterers

I forgot to note in VS-CHAT 2587 that CGCS 1045 = IRAS 05418-3224
is consequently a good and topical candidate for anyone wanting to
find themselves a "new variable", which I'm sure most people have
already realised!

It would have been friendlier of me, though, to include co-ordinates.
So:-

The CGCS gives the following full precision co-ords for 1045 at B1900:

RA 05h 40m 00.4s     DEC -32d 26' 07"

The IRAS_PSC gives the following co-ords for 05418-3224 at B1950:

RA 05h 41m 51.7s     DEC -32d 24' 44"  uncertainty ellipse 17"x5" at PA
92d

which is in very good agreement if the CGCS co-ords are precessed to
B1950.

Precessed to J2000 [feel free to independently check my calculations]
the CGCS 1045 B1900 values become the following J2000 co-ords:

RA 05h 43m 43.1s     DEC -32d 23' 28.6"


which in general lies roughly half a degree nearly due west of the
famous
"runaway star" mu Columbae.


Good luck to anyone interested [I'd have to stand on the roof on tiptoe
to
go for it from this latitude!]  Remember, it'll be red and quite faint
at photographic magnitudes, even if near maximum!  I'll guesstimate V of

approx. 10 if near maximum, with a 450ish day period, based on
considerations re the other stars noted in VS-Chat 2587 etc.


[NB Double checks of the NSV & NSVS revealed no candidate
object at this position.  DSS2 AAO R red plates show an object
at this position a fair bit brighter than an adjacent triplet of stars,
whilst
blue STScI SERC J plates show it to be much fainter than these three,
indeed nearing plate limit.  USNO A2.0 data, via Lowell web site, give
an
object of red mag 16.8, blue mag 20.2, 0.7" from the J2000 co-ords,
whilst
the "triplet" stars each have near equal blue and red magnitudes.
This suggests a relatively low B-V for CGCS 1045 of around 2 and a half,
and
V maybe even as low as 18! but it should be remembered that all the
above are epoch
dependent snapshots, and this could be near minimum]


Cheers

John

John Greaves, UK

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp