Guide Star and Image Catalogues

Image stabilization and concentration of flux are enabled using wavefront sensors (peripheral, on-instrument and adaptive optics, depending on the circumstance) with suitable guide stars. Preparation of an observation, including selection of guide stars, for example with the Observing Tool is assisted by having an image of the field.

As the guide stars and sky images are so central to the operation of Gemini they are available on-line locally as well as from a number of other sites on the internet. Links to guide star and sky survey catalogues (as well as cursory details) are as follows:

Guide (and other) stars:

• Tycho/Hipparcos - accurate positions, bright (1-10 milli-arcsec uncertainty, V~<11 mag)
• Local
• Pair search
• CADC
• GSC1 (V~<15 mag)
• Local
• CADC - Victoria, Canada
• STScI - Baltimore, USA
• ESO - Garching, Germany
• GSC2 (V~<18 mag)
• Local
• 2-MASS (near-infrared; J<15.8, H<15.1, K<14.3)
• IPAC - initial release of sources in 63 sq degrees

Digital sky survey images:

• DSS1 (1.0-1.7 arcsec pixels)
• Local
• CADC - Victoria, Canada
• STScI - Baltimore, USA
• ESO - Garching, Germany
• DSS2 (1.0 or 1.7 arcsec pixels)
• Local
• CADC - Victoria, Canada
• STScI - Baltimore, USA
• ESO
• 2-MASS (near-infrared)
• IPAC - initial release of 63 sq degrees

Last update August 31, 2000; Marianne Takamiya