The Sloan Digital Sky Survey (see www.sdss.org for general information)
will map one-quarter of the entire sky and perform a redshift survey
of galaxies, quasars and stars. The DR3 is the third major data
release and provides images,
imaging catalogs, spectra, and redshifts for download.
About DR3 explains what is new
in DR3, and lists remaining or new caveats and subtleties in the data.
Please refer to the credits
page for our sources of funding, participating institutions, how
to acknowledge the use of SDSS data in your publications. Please also
note how to refer to SDSS sources in
your publications using the proper IAU
nomenclature for SDSS sources.
Imaging
Footprint area |
5282 sq. deg. |
Imaging catalog |
141 million unique objects |
Data volume |
images | 6.0 TB |
catalogs (DAS, fits format) | 1.2 TB |
catalogs (CAS, SQL database) | 2.3 TB |
|
Average wavelengths and magnitude limits
(95% detection repeatability for point sources) |
u |
g |
r |
i |
z |
3551Å |
4686Å |
6165Å |
7481Å |
8931Å |
22.0 |
22.2 |
22.2 |
21.3 |
20.5 |
|
PSF width |
1.4" median in r |
Photometric calibration |
r |
u-g |
g-r |
r-i |
i-z |
2% |
3% |
2% |
2% |
3% |
|
Astrometry |
< 0.1" rms absolute per coordinate |
Spectroscopy
Spectroscopic area |
3732 sq. deg. |
Wavelength coverage |
3800-9200Å |
Resolution |
1800 |
Signal-to-noise |
>4 per pixel at g=20.2 |
Redshift accuracy |
30 km/sec rms for main galaxy sample (from repeat observations) |
Target magnitude limits for main samples |
Galaxies: Petrosian r <17.77
Quasars: PSF i <19.1 |
Spectroscopic catalog |
528,640 spectra, classified into
374,767 Galaxies |
45,260 Quasars (redshift <2.3) |
5,767 Quasars (redshift >2.3) |
50,369 Stars |
20,805 M stars and later |
26,819 Sky spectra |
4,853 Unknown class |
|
Data volume |
calibrated spectra ("2d") | 41 GB |
spectra, redshifts, line measurements ("1d") | 110 GB |
|
Previous data releases
For reference, we provide links to earlier data releases. The
current data release always provides both the largest sky coverage and
the highest-quality data and reductions.
This is version v3_20080930_1856 .
If you are using Netscape 4.x and see oversized fonts, please look at the workaround on the Credits page.
|