Celestia Forums

Hi, I'm new to the board as well as the program. And for the most part, new to astronomy. I have some coordinates for a star in the constellation Libra that I would like to find in the program. The program doesn't seem to take coordinates I have and I do not know how to convert them to the required coordinates. I hope guys can help me and I thank you in advance. Here's what I got:

Libra RA 15h 43m 11s D-11* 5'

Thanks in advance.

Jay

Jay,

Check out the link to the ESA's Hipparcos site below -
http://www.rssd.esa.int/index.php?project=HIPPARCOS&page=index

On the left side of that page you'll see a section titled "Catalogues".

The first entry, "Overview of the Catalogues", is a section with detailed information (pdf files) about the Hipparcos and Tycho catalogues.

The second entry, "Access the Catalogue Data", is a section with links to the search page... you'll find several different search tools available there.

Another way to locate the star you're interested in is to use the Simbad astronomical database.
Its coordinate query page will help you locate stars which are near those coordinates.

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

There's nothing at those precise coordinates. Where did you get them? Do you know if they are supposed to be J2000 coordinates or B1950 coordinates?

Simbad normally uses ICRS, which is essentially the same as J2000. (The coordinates of stars have changed since 1950 because the Earth's axis precesses (wobbles). Astronomers recently agreed to change to ICRS, a coordinate system that is not tied to the Earth's orientation.)

In ICRS coordinates, the closest star (which happens to be in Celestia) seems to be the variable star SV* ZI 1150, ~552 arc seconds away. It's also cataloged as HIP 76976 and is at
15h 43m 03.0966s -10deg 56m 00.590s

If you have B1950 coordinates, there are no HIP stars within a half-degree of that location.