Photo credit: Pauline Acalin

For Information on observing through the 60-inch Telescope, scroll through the options below:

Notice: The 60-inch and the 100-inch telescope sessions for the year are coming to a close on December 2, 2018. During the winter months, weather conditions often close the roads to the observatory and we use this down time to do maintenance on the telescopes. We will reopen the reservation calendar on Friday, March 1st, 2019.

  Mount Wilson Observatory’s 60-inch telescope was completed in 1908 by Observatory founder George Ellery Hale with funding from Andrew Carnegie. It was the world’s largest operational telescope until Hale went on to complete the Mt. Wilson 100-inch telescope in 1917. For a more detailed history of this revolutionary instrument, which became the model for all large observatory telescopes of the future, see the article "Building the 60-inch Telescope." Among the many important discoveries from the 60-inch telescope was Harlow Shapley’s revelation in 1918 that the accepted view of the time, that our Sun was near the center of the Milky Way Galaxy, was wrong. Shapley used the light gathering power of the 60-inch to show that our solar system is instead half way out toward the edge of our Galaxy. The telescope was a workhorse instrument for astronomy for over half a century and used by astronomical luminaries such as Edwin Hubble, Walter Baade, and Allan Sandage to unravel the secrets of stars and galaxies. Now retired from active scientific service, the 60-inch and the 100-inch telescopes are the largest in the world made exclusively available to the public. With their large light-collecting mirrors and the exquisite skies over Mount Wilson, these historic telescopes provide an unrivaled and unique astronomical experience.

Your Session Director will arrange your visit

  • Meeting Time: Chosen or agreed to by the Session Director, typically around Sunset. For safety and other logistic considerations, planning multiple additional arrival time(s) cannot be accommodated.
  • Parking: We can accommodate up to 10 cars or up to a 30-passenger bus to park at or near the telescope dome. Any greater number of cars or larger size of passenger bus will require special logistics and must be discussed with the Session Director well in advance of the session.
  • National Forest Adventure Pass: Only needed if the Session Director determines that special logistics parking is required. Go to if passes are required.
  • Cancellation: Your session confirmation or cancellation the day of the session may be done only by the Session Director. Weather, telescope/observatory operations and/or external reasons are some factors that may require cancelling the session.
  • Dome logistics and accommodations: Dome lights will be turned down to dim red for observing.
  • No Handicapped Access: The dome was built in 1908 and is not ADA-compliant, offering no access for those who cannot climb stairs and ladders. Visiting is not suggested for those with respiratory or heart problems due to the stairs and the 5700-ft elevation.
  • Chairs: Mount Wilson Observatory provides chairs.
  • Refreshments: We provide hot water, hot chocolate, coffee, tea, cups, and stirrers/spoons.
  • Smoking (including “vapors”) & Alcoholic Beverages are not permitted at Mount Wilson Observatory.
  • Restroom: Located inside the dome, on the ground level.
  • Photography: Non-flash photography through the eyepiece during the observing session will be permitted, with the approval of the Telescope Operator and Session Director. Special and advance approval from the Session Director is required for cameras or other devices to be mounted to the telescope. Before the session starts, feel free to take photographs of the telescope and Observatory grounds.
What to bring with you for the observing session
  • Clothing: Warm layers like sweater, coat, hat, etc. as the dome is not heated and the temperature in the dome can quickly drop. Sturdy closed-toed shoes/boots.
  • Flashlights: White flashlight when leaving the dome; red flashlight duriing the observing time.
  • Refreshments: You may bring your own snacks and non-alcoholic beverages to be consumed on the observing level.
  • Observing list: While the Telescope Operator has a list of appropriate objects for the 60-inch Telescope, please feel free to bring your own observing list. The Telescope Operator’s decision is final on whether a particular object can be observed at a particular time.
The 2018 fee rates are $1,000 per half night and $1,700 per full night for a group of up to 25 people. We are able to schedule a half night of observing for the first half of the night only. Logistical problems preclude us from scheduling two different groups for the first and second halves of the night. We also do not provide a service for matching different groups to share the same reservation. Occasional individually-ticketed nights are announced during the season from this website and from our Facebook Page.

The 60-inch and the 100-inch telescope sessions for the year are coming to a close on December 2, 2018. During the winter months, weather conditions often close the roads to the observatory and we use this down time to do maintenance on the telescopes. We will reopen the reservation calendar on Friday, March 1st, 2019.

Scroll through the calendar to see if the date you want has already been booked. Please note, however, that some unbooked dates may not be available if someone else has already asked for the date and it has not yet been finalized and the calendar updated.
There are no services available for the period you selected.
You must select at least two days
You must select at least [min] days
You must select more than [max] days
You must select at least [min] hour
You must select more than [max] hour
<2018> November
Oct 29
1 available
Oct 30
1 available
Oct 31
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
1 available
Dec 1
Dec 2
Please check the available dates on the previous tab before requesting a specific date. Please be sure to check the boxes in the last section and click the submit button to send Requests are processed in the order that they are received.
60" Telescope Reservation Request

Step 1: Contact Information

Contact Name
Use this format (xxx) xxx-xxxx !
Use this format (xxx) xxx-xxxx !

Step 2: Details

Important: Check the calendar in the previous tab. Select any date you wish to observe that says "Available."
In the event that another party has already requested your first choice and it has not yet been finalized and entered into the calendar, enter an alternative date if possible. Enter "none" if not.
Limited to 25 persons total per visiting group
1 adult is required per 5 minors. Children under 12 are not permitted (NO EXCEPTIONS). The total of adults and minors is limited to 25.
Ex: Private Vehicles, 4 or Bus, 1. Parking is limited to 10 vehicles. Carpooling from the base of the mountain is strongly encouraged. It saves gas too!

Step 3: Terms of Agreement

For telescope users interested in taking photographs, click here for a PDF file with helpful information on how to get the best images at your 60-inch Telescope viewing session.

For current weather conditions on Mt. Wilson, go to Weather Underground.

The 60-inch Telescope was the largest in the world from 1908 to 1917, when Mount Wilson's 100-inch took the title. Photo credit: Heven Renteria
Saturn imaged through the 60-inch telescope in July, 2016. Exceptional sub-arc second seeing combined with the 60-inch's aperture shows remarkable details (without any image processing.) Photo credit: Pauline Acalin
On December 24, 1908, George Willis Ritchey photographed the Great Nebula in Orion, the first exposure made with the 60-inch Telescope. A brilliant optician, he designed the telescope and figured it's large glass mirror, and in the process put astronomy on a new path. In addition to revolutionizing astrophotography with the 60-inch, he later developed the Ritchey-Chrétien optical configuration which is the design of choice for most of today's giant telescopes. Credit: Carnegie Observatories
As twilight approaches and a night of observing begins, a member of the Orange County Astronomers club gets a peak at a low planet through the eyepiece of the 60-inch telescope. Credit: Pauline Acalin
The moon as seen through the 60-inch telescope. The terminator, where sunlight and shadow meet, on a waxing gibbous moon. Credit: Pauline Acalin

A visitor observing with the 60-inch telescope. Photo: Babak A. Tafreshi