Page 1 of 1

The Strange case of Gliese 563.2

Posted: 06.05.2003, 17:29
by Apollo7
This is one of those Stars that I just can't figure out. In my quest to add stars to Celestia I came upon this one, seemingly ordinary. It carries a HIP number, specifically 72511, but interesttingly enough is not in Celestia. Daring to add it I started checking around. Well as I found Gliese is a binary system, consisting of two components, Gliese 563.2 A &B. Nothing out of the blue there.

I went and checked Oppenheimer's Catalogue and found the entries, however to my surprise the parallax between the two varried by quite a bit. With that so did the RA and Dec. The Data I collected at the outset was:

Gl 563.2 A - RA: 222.385875, Dec:-26.105694, Parallax: 235.24 mas
Gl 563.2 B - RA: 222.38233, Dec: -26.11167, Parallax: 221.80 mas

This data yeilds a distance of 13.864989 Ly for A, and 14.705139 Ly for B, a difference of about .840150 Ly, such a distance would lead me to believe these two stars are not even related. However the intrigue continues:

I checked RECONS, and a couple of other sites dealing with nearby stars and found nothing. Next I tried the internet stellar database and found the entry. HIP 72511, Gl 563.2, but this time with a distance of 68 Light Years, or 21 Parsecs. The Database gives the coordinates as

Gl 563.2 A - RA: 222.385375, Dec: -26.10625
Gl 563.2 B - RA: 221.67, Dec: -25.9

The Database gives the two stars 625 AU of breathing room in their orbit but then reveals nothing more.

Anyway I'm not sure where these two M3 V dwarfs belong, I'm left to wonder who is right (if anyone) and if the stars are related at all (which they might not be), anyone care to offer any insight into this?

Posted: 06.05.2003, 18:44
by HankR
NASA's NStars database identifies this system as NS-1449-2606 A/B and provides the following data (and more):

Code: Select all

                  A                        B

HIP#            72511                    72509
RA              14 49 32.6               14 49 31.8
DEC            -26 06 20.5              -26 06 42.0
APP VMAG        11.86                    12.07
ABS VMAG        10.69                    11.08
DIST (LY)       51.35                    51.35
DIST (PC)       15.753                   15.753
PARALLAX         0.06348                  0.06348
PAR UNCER        0.00757                  0.00757
SPEC TYPE       M1                       M1.5


Here's the url:
http://nstars.arc.nasa.gov/searches/starinfo.cfm?partb=1449m2606&starpage=0

Re NStars (from the website):

"The NASA NStars research project was originated in 1998 and is based at the Ames Research Center in California. Its mission is to be the most current, complete and accurate source of scientific data about all stellar objects within the current study radius of 25 parsecs. At present this includes approximately 2600 stars. The techniques, methods and know how being developed to accomplish this will form the basis to expand this knowledge base further out into our galaxy. NStars provides research grade internet capabilities to astronomers and other scientists, support for NASA deep space missions and basic star information to students and amateur sky observers.

"This database is meant to be more than a compilation of published data regarding stars within 25 pc distance. The goal of the project is that posted data will have been quality-controlled, filtered and regularized to common standards whenever possible. At present this quality vetting applies best to data for stars within 10 pc distance, almost entirely supplied from Todd Henry's personal research RECONS database. Data from the CNS91 catalog and other sources are supplied in some cases when necessary.

"The NStars database is still under construction as of 01 August 2001 (sic). Data and functions are being added daily. At this point we regretfully must say 'caveat emptor'."

- Hank