This is the description of the namespace http://docs.g-vo.org/rdf/refframe as of 2019-03-15.
This vocabulary is not yet approved by the IVOA. This means that terms can still disappear without prior notice.
A collection of reference frames in common use in astronomy, organised by top-level categories (equatorial, galactic, etc). Wher no more precise reference are given, http://www.iaufs.org/res.html is often of help.
| Predicate | Label | Description | Parent | Preferred |
|---|---|---|---|---|
| EQUATORIAL | Equatorial | Umbrella term of all equatorial frame. Only use for old, pre-FK4 equatorial coordinates. | ||
| ICRS | ICRS | International Celestial Reference System as defined by 1998AJ....116..516M. | #EQUATORIAL | |
| FK4 | FK4 | Positions based on the 4th Fundamental Katalog. If no equinox is defined with this frame, assume B1950.0. | #EQUATORIAL | |
| FK5 | FK5 | Positions based on the 5th Fundamental Katalog. If no equinox is defined with this frame, assume J2000.0. Applications not requiring extremely high precision can identify FK5 at J2000 with ICRS. | #EQUATORIAL | |
| eq_FK4 | FK4 | Old VOTable COOSYS term for FK4. | #EQUATORIAL | #FK4 |
| eq_FK5 | FK5 | Old VOTable COOSYS term for FK5. | #EQUATORIAL | #FK5 |
| ECLIPTIC | Ecliptic | Ecliptic coordinates; the ecliptic of J2000.0 is assumed. | ||
| ecl_FK4 | Ecliptic (FK4) | Old VOTable COOSYS term ecliptic coordinates for the FK4 ecliptic (of B1950.0). | #ECLIPTIC | |
| ecl_FK5 | Ecliptic (FK5) | Old VOTable COOSYS term ecliptic coordinates for the FK5 ecliptic (of J2000.0). | #ECLIPTIC | #ECLIPTIC |
| GENERIC_GALACTIC | Galactic | Umbrella term for Galactic coordinates. If at all possible, use a more specific term, as historically, many different conventions have been in use. | ||
| GALACTIC_I | Old Galactic | Old, pre-1958, Galactic coordinates. See 1960MNRAS.121..123B for details. | #GENERIC_GALACTIC | |
| GALACTIC | Galactic | Galactic coordinates, modern definition: Pole at precisely FK4 B1950 192.25, 27.4, origin at approximately FK4 B1950 265.55, -28.92. See 1960MNRAS.121..123B for details. | #GENERIC_GALACTIC | |
| galactic | Galactic | Old VOTable COOSYS term for GALACTIC. | #GENERIC_GALACTIC | #GALACTIC |
| SUPER_GALACTIC | Supergalactic | Supergalactic coordinates (pole at GALACTIC 47.37, +6.32, origin at GALACTIC 137.37, 0. | #GENERIC_GALACTIC | |
| supergalactic | Supergalactic | Old VOTable COOSYS term for SUPER_GALACTIC | #GENERIC_GALACTIC | #SUPER_GALACITC |
| AZ_EL | Azimuth/elevation | Local azimuth and elevation. (Ground-based observations; Azimuth from North through East.) | ||
| BODY | Body Coordinates | Generic bodycentric coordinates. Data annotated in this way cannot be automatically combined with any other data. Use or create more specific terms if at all possible. | ||
| UNKNOWN | Unknown reference frame | Unknown reference frame. Only to be used as a last resort or for simulations. Data annotated in this way cannot be automatically combined with any other data. | ||
| xy | Unknown reference frame | Old VOTable COOSYS term for UNKNOWN | #UNKNOWN | |
| barycentric | ? | Old VOTable COOSYS term TO BE CLARIFIED | ||
| geo_app | ? | Old VOTable COOSYS term TO BE CLARIFIED |