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Eroica
2011-Apr-09, 03:45 PM
HU 1353 is listed in Burnham's Celestial Handbook as a double star in Horologium, but I have been unable to confirm this.

According to Eagle Creek (http://www.eaglecreekobservatory.org/eco/doubles/pf/hor.html), the star in question is HD 20334 (which does match Burnham's coordinates).

Does anyone know if Burnham's information is correct?

Separation: 2.6"
Position Angle: 191 degrees
Year: 1922
Magnitudes: 8.5 and 11 (HD 20334 is 8.27 visual magnitude)
RA and DEC 03124s5615 (= 03 HR 12.4 MIN, South 56 deg 15 mins) for Epoch 1950.0

Thanks

Eroica

StupendousMan
2011-Apr-10, 01:40 AM
Go to SIMBAD

http://simbad.u-strasbg.fr/simbad/

choose "query by identifier", and type "HD 20334" into the search box. Press "submit", and you'll receive a wealth of information about the star. You can click on links near the end of that list to see entries for this star in a number of catalogs.

Tycho shows no evidence for duplicity, nor does 2MASS. Those are two strong reasons to believe that it is not a double star with the given separation and magnitudes, as each of these surveys would have noticed the companion.

The 2MASS image does show a much fainter star about 12 arcsec away at a PA of 13 degrees.

Hungry4info
2011-Apr-10, 03:48 AM
The SIMBAD reference search suggests there have been no references to this star in scientific literature for as long as they have kept count (the year 1850).

Forever alone...

Eroica
2011-Apr-11, 02:08 PM
Go to SIMBAD

Already been there, StupendousMan, but thanks for the input. I've learnt not to be hasty when correcting Burnham - he usually turns out to be right.

StupendousMan
2011-Apr-11, 03:59 PM
Well, as I pointed out, you could look at a 2MASS image and see for yourself, using SIMBAD's Aladin tool. There isn't anything at Burnham's location now ....

Eroica
2011-Apr-12, 11:48 AM
The 2MASS image does show a much fainter star about 12 arcsec away at a PA of 13 degrees.

I don't see that star. The two closest stars to HD 20334 seem to be nearly 60 arcsec away at PA 080 and 280 approximately.

StupendousMan
2011-Apr-12, 12:22 PM
Ah, that star only appears in J, not in H or K, or even the DSS I-band. Perhaps it was an asteroid ... no, probably not at -55 Dec. Hmmm. Mystery.

ngc3314
2011-Apr-12, 01:04 PM
Ah, that star only appears in J, not in H or K, or even the DSS I-band. Perhaps it was an asteroid ... no, probably not at -55 Dec. Hmmm. Mystery.

Main belt, sure, but NEOs can show up anywhere in the sky. Briefly. I have a sequence of one crossing the field of M81. OTOH, something that close would likely trail quickly. On the gripping hand, the time span of all overlapping 2MASS exposures at a single point was only something like 10 seconds, and JHK were done simultaneously (so it would have to be pretty faint to only sneak into the J image).

Eroica
2011-Apr-12, 04:58 PM
Ah, that star only appears in J ....

Ah, yes. I see it now.