Astronomical Catalogs Query Pages

Hints and Tips for Easier Use

Here are some hints and tips to help you deal with the most common user difficulties with the star catalog interface.

Can't Match String

Some of these catalogs are quite old, and the data were originally formatted using FORTRAN programs writing to punch cards. There may be some odd conventions in the formatting of names; you may find that an object called NGC123 is called NGC-123 in one catalog, NGC<1 space>123 in another, and NGC<3 spaces>123 in yet another. It depends on how the original catalog author interpreted the name string.
The wildcard (%) symbol can be very helpful here. If your search for NGC123 fails, you might want to try NGC%123 -- this may match more data than you wanted, since it will return NGC 1123 as well, but it will ignore any number of intervening spaces. Using the "write your own" entry box at the foot of the page, you can be even more clever and search for Name like 'NGC %123'

Exceeded Limit?

With a complex query it is sometimes easy to get distracted (particularly since you can't see all of your search parameters at once); when you get 0 records returned, be sure to check the SQL statement and verify that all the values you specified are within the expected ranges of values for their respective columns. A typo in the RA field can lead to great frustration.