Release History for the SuperCOSMOS Science Archive
This page will record the history of SSA releases. Bug fixes, etc, will
first be announced on the SSA_Announce email distribution list -
contact Mike Read (email@example.com) to subscribe to that - and
then subsequently recorded here.
- 2020-02-27: bug report:
- The Modified Julian Date values (column mjd) in table Plate have been found to be systematically in error for a significant fraction
of the rows. Some 113 values are incorrect by exactly 2.0 days; 2800 are off by 1.0 days and 3 are off by 0.26 days.
Consequently column mjd of table Plate should not be employed when precision of better than a few days is required.
For UKSTU plates in the southern hemisphere a fix is being developed and will be reported here when implemented in the online SSA.
- 2013-08-06: bug report:
- It has been brought to our attention that the Source table is seriously incomplete in a small region near
the North Celestial Pole bounded by 220 < RA < 330 and Dec > +86. The Detection table is, however,
unaffected by the problem in this region so complete single-passband catalogues in the area can be made by querying that table
(note however that proper motions, colour-corrected photometry and the recalibrated galaxy magnitudes are
consequently unavailable in the affected area).
- 2008-07-22: Full SSA placed online. The final, full-blown
all-sky version of the SSA is now available. Known features/bugs include:
- POSS-I E field 1038 at 16 hours, -12 degrees is missing from the SSA
so there are no first epoch red parameters in Source or Detection for parts
of SSA fields 655, 656, 727 and 728.
- 2005-10-31: The USNO-B database held in the archive has been found to be
corrupted and will remain unavailable until further notice.
- 2004-12-03: Service switched to new hardware configuration. The
databases comprising the original SSA v1.0 (see below) have been redeployed
on server with a reconfigured disk subsystem (employing hardware RAID
contollers) with the intention of eliminating any unplanned downtime due
to disk subsystem instability (the problem has been traced to Ultra320
connectivity problems). The data are identical to those as originally
released, but the archive now also includes the catalogue products from the
Sloan Digital Sky Survey (SDSS) Data
Release 2 (DR2) along
with a cross-neighbour table (as exists for DR1 and the EDR).
- 2004-04-23: Release of SSA v1.0. This covers the whole southern
hemisphere (Dec < +3.0 degrees) in the photographic BJ, R (at
two epochs) and I bands: for more details see the
Data Overview page. The database includes CrossNeighbour tables
(i.e. listings of sources within 10 arcsec of each SSA source) for the
Sloan Digital Sky Survey (SDSS) Early Data
Release (EDR) and Data
Release 1 (DR1), as well
as the USNO-B1.0
and both the Extended and Point Source Catalogues from the 2 Micron
All Sky Survey (2MASS). The
spatial indexing within the v1.0 SSA is implemented using v1.0 of the
Hierarchical Triangular Mesh (
HTM) code developed at Johns Hopkins University and implemented in the
EDR version of the SDSS SkyServer database.
WFAU, Institute for Astronomy,
Royal Observatory, Blackford Hill
Edinburgh, EH9 3HJ, UK