Radio Galaxy Zoo Talk

NVSS SDSS

  • 1001G by 1001G

    IF NED SAYS NVSS RADIO SOURCE IS THAT THE RADIO SOURCE OR COULD IT BE A SDSS SOURCE.
    NVSS & SDSS WHAT ARE THEY.

    Posted

  • enno.middelberg by enno.middelberg scientist, translator

    The same physical object, that is, the same conglomerate of matter, emits radiation at different wavelengths, such as in the optical and in the radio. Therefore the same object will appear in catalogs made at different wavelengths (for example in a radio catalog such as NVSS and an optical catalog such as SDSS), and in these catalogs gets a catalog number. There is no "master" catalog which contains an "official", or "final", or "reference" identification. The tedious part is now to cross-identify two catalog entries with one another, to determine if the emission registered at two different wavelengths comes from the same physical object. This is the main goal of radio galaxy zoo - to cross-identify radio sources with optical or infrared sources. Hence the "or" in your question is wrong - it is an "and": the radio source we're seeing here is known as NVSS J132602+031653 and SDSS J132601.88+031637.4. And at each wavelengths several names can peacefully co-exist.

    When you go to NED and search for, say, 3C273, you will get a list of more than 100 names for the same object. They're all just names for the same physical object, and none of them is wrong or right.

    Posted

  • 1001G by 1001G

    Thanks for a very clear reply.

    Posted