(manual in progress)


The Coude Auxiliary Telescope (CAT) was added at the Shane 3-meter Telescope in 1969 to provide an independent feed for the latter's coude spectrographs. Its 0.6-meter primary has one-twentyfifth the collecting area of the 3-meter but, due to its advantageous plate scale, in practice the CAT is relatively more efficient than would be expected from the ratios of the telescopes' apertures alone. The CAT may be used whenever the 3-meter is configured at prime or cassegrain focus.

The CAT has the same focal ratio (f36) as the Shane's coude focus, and its beam is fed to the spectrographs at the same angle through the same entrance slit. The two telescopes thus appear optically identical to the spectrographs and all instructions pertaining to the latters' use with the 3-meter apply equally well to their use with the CAT.

The CAT is available to the University of California astronomical community by subscription. As with all Lick telescopes, prospective CAT users must complete the appropriate time application form.

The CAT is a user-operated telescope. All new users must be checked out by a resident astronomer on their first night. Please ask for this on your time request.

Please direct questions to Thomas Lowe ( or Support Astronomers (

Thomas Lowe
April / 2010