George Mason Observatory

Welcome to the George Mason University Observatory

The George Mason Observatory, located on the Fairfax Campus of George Mason University, is a space where research, education, and public service come together under the stars. Operated by the Department of Physics and Astronomy in the College of Science, the observatory provides students and the community with unique opportunities to explore astronomy through hands-on experience with professional-grade equipment.

Observatory dome under clouds with trees

Visit the Observatory

Each week, the observatory opens its doors to the campus and local community. Public tours, group visits, and special events offer immersive experiences that bring the universe closer to home.
We are closed for the summer. We will resume our tours and events in September. Our events schedule will be posted the last week of August

The George Mason University observatory is primarily an outdoor facility. We recommend checking the weather forecast in advance and dressing appropriately for outdoor conditions. For safety, we strongly encourage all visitors to wear closed-toe shoes.

Please note that the observatory dome is not fully accessible. If you have any accessibility needs, contact us at GMUObservatory@gmail.com prior to your visit so that we can provide more detailed information and support your experience.

To maintain optimal viewing conditions, the dome remains as dark as possible during telescope use. We kindly ask that visitors refrain from using white light sources in dark areas. This includes, but is not limited to:

Phone screens
Flashlights
Flast Photography
Light-up shoes

Photography is welcome in and around the facility. However, please avoid using flash in dark areas such as the dome while observing is in progress. We also ask that visitors obtain permission before photographing observatory staff.

Smoking and vaping are not permitted on the observatory roof or within any observatory facilities. Weapons, alcohol, drugs, and motorized vehicles are strictly prohibited.

Children must be accompanied by a parent or guardian at all times.

Please be respectful toward all observatory staff members and fellow visitors.

The observatory is closed for the summer. Our tours will resume in September.
George Mason’s observatory offers free public tours on Wednesdays, Thursdays, and Saturdays throughout the academic year, weather permitting. No registration is required to attend.

When weather conditions are favorable, we offer open-dome tours. During these sessions, guests can view the night sky using our fully operational 32-inch Ritchey–Chrétien telescope, one of the largest on the East Coast accessible to the public.

If poor weather prevents live viewing, we host closed-dome tours, which still provide an educational experience. Visitors can see the telescope up close, learn how it operates, and engage with topics such as astrophotography, observational techniques, and current astronomical research.

Poor weather conditions include humidity over 80 percent, wind speeds over 20 miles per hour, precipitation, heavy cloud cover, or nearby wildfire smoke.

Tours begin promptly, and we recommend arriving a few minutes early. Please meet your guide at the reception area just inside Research Hall, near the building’s main elevators.

Evenings Under the Stars are held on the last Saturday of each school month and include a free 12 to 15-minute planetarium presentation. The event takes place in the atrium of Exploratory Hall (under the prehistoric whale skeleton). Space is limited and advance sign-up is required.

The observatory is closed for the summer. Our events will resume in September

The planetarium environment is kept dark for optimal viewing and may include flashing lights. If you are sensitive to these conditions, we recommend attending a different public event.

This event is not intended for scout groups or large parties. If you would like to schedule a visit for a group, please contact us in advance to arrange a private tour.

Two people standing in front of an inflated dome

We offer free private tours for scout troops, school groups, and community organizations. These visits can include telescope viewings or tailored planetarium shows. Programs are adapted to meet the interests and educational levels of your group. Private tours are available by request through GMUObservatory@gmail.com

We collaborate with local schools and community groups to deliver interactive astronomy experiences. Whether at the observatory for a field trip or off-site at a STEM event, we are excited to help students learn about the cosmos. To request an observatory field trip or planetarium presentation, email GMUObservatory@gmail.com

Quick Facts

1,000+

The observatory allows over 1,000 people every year to view the cosmos and learn from experts

32"

Our primary telescope is 32" in diameter, making it one of the largest campus telescopes on the East Coast!

Our Mission

At George Mason observatories, our mission is to inspire curiosity, foster scientific understanding, and ignite a passion for the wonders of the universe among individuals of all ages and backgrounds. We aim to be a leading public observatory and planetarium dedicated to providing enriching educational experiences, engaging outreach programs, and awe-inspiring opportunities for celestial exploration.

Education and Outreach
We strive to be a hub of astronomical knowledge by providing accessible and engaging educational programs, workshops, and interactive exhibits. Our commitment to diverse learning opportunities ensures that individuals of all ages and abilities can explore the marvels of space and develop a deeper appreciation for the cosmos.

Stargazing and Observations
As a premier university observatory, we offer advanced telescopes and equipment that enable visitors to observe celestial events, planets, stars, and other astronomical phenomena with clarity and precision. Our team members guide guests through stargazing experiences that foster a meaningful connection between humanity and the universe.

Planetarium Shows and Immersive Experiences
The observatory’s digital planetarium presents immersive shows that transport audiences to the far reaches of the universe. Through the use of storytelling and cutting-edge technology, we offer memorable experiences that bring astronomical concepts to life and inspire curiosity and exploration.

Scientific Research and Discovery
We are committed to advancing astronomical research and contributing to the global scientific community. Our collaborations with astronomers and academic institutions support innovative research and ensure that our programs reflect the latest developments in space science and exploration.

Community Engagement
We engage with both local and global communities to promote inclusivity and diversity across all programs. The observatory is a welcoming and inclusive space where people from all backgrounds are invited to celebrate and explore the cosmos together.

Conservation of Dark Skies
We recognize the importance of preserving natural nightscapes and reducing light pollution. Through educational initiatives and public programs, we raise awareness about the effects of light pollution on both astronomy and the environment and advocate for sustainable lighting practices.

Conservation of Earth’s Orbital Environment
We acknowledge the increasing risks posed by orbital debris and the expanding commercial satellite industry to both ground-based astronomy and life on Earth. The observatory supports efforts to raise public awareness, promote technical solutions, and encourage responsible policy that protects Earth’s orbital environment.

Support our observatory!

The Mason Observatory is financially supported by the Department of Physics and Astronomy, and donations from people like you! Donations, in particular, help us to purchase everything from imaging equipment for professional-grade research to the shows we play in our planetarium. That is why even a few dollars can make an impact.

Make a contribution

About Our Facility

Many people are unaware that George Mason University had two previous observatories. The first of these observatories officially opened on October 6, 1975, with construction beginning in 1972. Though informally known as the Herschel Observatory by the Department of Physics, this name was never officially adopted. The observatory was built by students John Whalan, Chipper Peterson, and Bob Veenstra, under the supervision of Bill Lankford.

In the fall of 1975, Menas Kafatos took over supervision of the Herschel Observatory. Located in a pig shed adjacent to the Mallory House, across Route 123 from the main campus, the observatory was eventually dismantled to make way for the Field House. A second observatory was then constructed on the athletic fields but was ultimately demolished by 1980 due to vandalism.

For decades, there were plans to establish a new observatory at George Mason, with proposed sites including the rooftops of Science and Technology I (Planetary Hall), Science and Technology II (Exploratory Hall), and Academic IV (Innovation Hall). In 1982, a petition circulated by Harold Geller was received by then-President Johnson, highlighting the need for a new observatory. Despite strong support from faculty like Lankford, Kafatos, Lieb, Ellsworth, Ehrlich, Becker, Wallin, Geller, and Dworzecka, as well as administrators such as Provost Stearns, Vice-Provost Hill, Dean Struppa, and Dean Kafatos, financial constraints continually halted progress.

Today, George Mason University proudly hosts its observatory atop Research Hall on Fairfax Campus. The Research Hall observatory features an impressive collection of telescopes, including a 32-inch Ritchey-Chrétien Cassigrain reflector. Like its predecessor, the modern observatory is heavily utilized for public outreach events. As Kafatos predicted in a 1978 interview with Mason’s Broadside, the observatory serves as a valuable resource for the community.

White building with sign reading "GMU Herschel Observatory"

John Whalan, Herschel Observatory, 1970s

Telescopes and Equipment

The George Mason Observatory houses one of the largest university-operated telescopes in the region, a 32-inch Ritchey-Chrétien reflector. This telescope allows for both visual observation and digital imaging.

Mason student looking through a telescope

In addition to our primary telescope, we operate a range of portable telescopes and observing tools, including:

8-inch and 12-inch Schmidt-Cassegrain telescopes
152-millimeter hydrogen-alpha solar telescope
16-inch Dobsonian telescope
SBIG STX-16803 CCD

Objects Captured by Students Using Our Equipment

All images of objects above were captured using our SBIG STX-16803 CCD with the appropriate filters. All images are property of Mason, please contact us for usage permissions.