Observing With the 60-inch Telescope



The Mt. Wilson Observatory 60-inch telescope is used by:



Professional Astronomers

The 60-inch is available for scientific research projects. The telescope is presently under-utilized, and time is available. This fine instrument is still very capable, and it would be ideal for use by graduate students for their dissertation research. To cover operating expenses, there must be a charge. To schedule telescope time, contact the Mt. Wilson Institute.



60-inch Nights for MWOA Sustaining Members

The chief benefit of being a sustaining member of MWOA is the opportunity to observe through the Mt. Wilson 60-inch telescope. This historic 1908 instrument, the world's first modern telescope, is George Ritchey's masterpiece. The optics of the 60-inch are diffraction limited, plus the seeing on Mt. Wilson is often excellent (sub-arc-second), especially in the Summer. The inversion layer that traps smog far below also makes good seeing on the mountain top. Although no longer located in a dark-sky site, you can still visually see the central star in the Ring Nebula. The presence of the lights from L.A. may be a nuisance, but they have NOT ruined Mt. Wilson for astronomy. Often the marine layer comes in and low clouds cover L.A. (Mt. Wilson is far above these clouds). At these times, the sky gets quite dark, and this is also when the seeing is the best. The telescope is especially good on planets, and you haven't lived until you have seen M13 and the Orion Nebula through the 60-inch!

You can be a celestial tourist from dusk to dawn, or you can go home whenever you wish. No more than 25 people are allowed on a given night, so there are no crowds. These sessions are mainly for visual viewing. We use the f/16 Cassegrain focus, which is conveniently located. On special occasions when there aren't people waiting to look, limited photography is permitted through the eyepiece.

We usually have cookies, soft drinks, and hot water, but you might wish to bring a sandwich. The Observatory is at 5800 feet elevation, so bring a jacket in Summer and a warm coat in the Spring and Fall. It also helps if you bring a folding chair. Some people even bring a sleeping bag. Because we can choose which objects to look at, you might like bringing a list of some of your favorite objects (with precessed coordinates) to suggest.

See the Directions page for how to get to the Observatory. At regular times around sunset, a docent will come and open the gate to let you in. For the 60-inch nights, you can drive all the way in and park near the dome, and no "Forest Adventure Pass" is required.


For the year 2008, four nights have been scheduled. All are Saturday nights and all are near the New Moon.

MWOA 60-inch 2008 Schedule

Saturday May 3 (reservations open April 5)
Saturday June 7 (reservations open May 10)
Saturday August 2 (reservations open July 5)
Saturday September 27 (reservations open August 30)


New Rules: To solve some problems in scheduling for these events, a new set of rules has had to be adopted by the MWOA Board. Please read carefully:

MWOA reserves four or five nights each year on the 60-inch telescope for Sustaining Members to recognize their contributions to MWOA activities on behalf of the Mount Wilson Observatory. Since there is a limit of 25 persons maximum at any one session, rules for reservations must be established to ensure that as many Sustaining Members as possible may be accommodated in any one calendar year. To encourage others to become Sustaining Members, guests may attend subject to these rules. All reservations are to be made through Don Nicholson by e-mail or phone at (310) 476-4413, or through his designated representative.

  1. No reservation for any session will be taken until four weeks prior to the session.
  2. Except as noted below, reservations will be accepted in the order they are received.
  3. No reservations for Sustaining Members or guests under 12 years of age may be made.
  4. If a total of 25 Sustaining Members and guests are reserved at 48 hours prior to a session (Thursday evening for a Saturday session) the reservations for that session will then be closed.
  5. Should the number of reservations for Sustaining Members and guests reach 25 prior to 48 hours before a session and should an additional Sustaining Member then wish to reserve, guest reservations will be revoked on a last-in, first-out basis. The Sustaining Member’s reservation will then be made subject to the following conditions.
  6. Priority for reservation at any session will be given to those Sustaining Members who have not previously attended a session in the calendar year.
  7. The more sessions a Sustaining Member attends in a calendar year the lower that Sustaining Member’s priority becomes for succeeding sessions.
  8. Non-attendance with failure to cancel the reservation prior to 48 hours before the session will be considered as attendance for the purpose of determining priorities.
  9. Sustaining Members may bring no more than two guests to a session and no person may attend as a guest at more than one session in a calendar year.


60-inch Nights for Other Amateur Observers

Amateur observing through the 60-inch is not restricted to MWOA. Astronomy clubs and other interested groups and individuals can also reserve the telescope for their own functions. There is a per-night charge. Arrangements must be made ahead of time. For more information and a request form, click HERE.