The Crossley 36" Reflector, originally constructed by Andrew A. Common
in 1879, was moved to Lick Observatory in 1896. Improvements to the
telescope (to the extent that no original telescope parts remain),
occurred during the late 1800's through about 1910 to bring the
telescope to its current configuration. The f/5.8 primary mirror
yields a plate scale at the prime focus of 38.6 arcseconds per
The Crossley is not a computer controlled telescope and has only
tracking motors, thus the telescope must be slewed by hand. This
poses unique hazards in the dome and when working around the
Lick Observatory does not provide any facility instruments for use at
the Crossley Telescope. A prime focus spider is available for
observers to mount their own instruments. Mounting an observer
provided guide/acquisition camera is also possible. Contact a support
astronomer for information on mounting instruments at the Crossley
before applying for telescope time to make sure that the hardware is
compatible or that proper mounting hardware can be constructed.
Information in this manual is taken nearly verbatim from The
Crossley Telescope, Lick Observatory Technical Reference 5, by Rem
Stone. Thus some information may be out of date, though the bulk of
the material is current.
The Crossley Telescope is available to the University of
California astronomical community by subscription.
Follow these links to: Call for Small Telescope Proposals
Small telescope observing time application forms The Crossley is a user-operated telescope. All new users must be checked out by a resident astronomer on their first night. Please request support on your time application. Please direct questions to a Mount Hamilton support astronomer, firstname.lastname@example.org.