Join the Denver Astronomical Society for a special International Observe the Moon Night Open House at Denver University’s historic Chamberlin Observatory.

International Observe the Moon Night is a worldwide celebration of our nearest celestial neighbor. Held each year when the Moon is near First Quarter, the event brings people from around the globe together to observe, learn about, and appreciate the Moon’s role in science, exploration, and human culture. This year, the celebration takes place on Saturday, September 19, 2026, making it a perfect evening to explore the Moon’s mountains, craters, and other fascinating features.

Weather permitting, visitors can view the Moon through Chamberlin Observatory’s historic 20-inch Alvan Clark-Saegmuller refractor telescope. DAS members will also have telescopes set up on the south lawn, providing additional views of the Moon and other celestial sights.

If you recently purchased a telescope and need help learning how to use it, arrive before dark and bring it with you. DAS members will be happy to help you get started. Don’t own a telescope? No problem! This event is designed for everyone, whether you’re a longtime observer or simply curious about the night sky.

No registration is required, but we would like to keep track of a headcount for planning purposes. If you plan to attend, please register at https://www.eventbrite.com/e/open-house-international-observe-the-moon-night-tickets-1998289881829

We look forward to seeing you under the Moonlit sky!

Participating Organizations and Activities

Denver Astronomical Society will host telescope viewing, limited-capacity tours and viewing inside the historical Chamberlin Observatory, and a variety of Moon-themed activities for visitors of all ages. DAS volunteers will be available throughout the evening to answer questions, guide activities, and help visitors explore the night sky.

DarkSky Colorado – DarkSky Colorado will have an outreach table featuring educational brochures, free stickers, and representatives available to chat with attendees about dark sky conservation.

Planetary Science Institute will bring meteorites, “meteorwrongs,” Moon and Mars globes, and information about PSI’s Colorado work and Artemis Participating Scientists. Visitors can also meet PSI scientists, ask questions about planetary science, and enjoy a few space-themed treats.

Space Foundation Discovery Center will join the event as a participating science education partner, helping connect visitors with the broader world of space exploration, discovery, and hands-on learning.

Colorado Parks and Wildlife / Jackson Lake State Park will help visitors explore the nighttime world of Colorado wildlife with nocturnal animal skins and skulls, a full bat skeleton display, and educational materials about the animals that share our dark skies.

DU Society of Physics Students is a community of undergraduate students with a passion for sharing physics and astronomy with the public. They will offer hands-on demonstrations for curious kids of all ages, exploring how the Moon-Earth system works, the colors that make up moonlight, what a spinning planet or moon feels like, and how craters form. They will also have special kid-sized telescopes for easy Moon viewing.

MSU Denver will bring a full slate of hands-on astronomy experiences, including solar and lunar viewing telescopes and interactive stations featuring a scaled Solar System, a gravity-well demonstration, UV and glow-in-the-dark bracelet making, and paper rockets with a small air launcher.

CU Denver will invite visitors to explore the Moon like Artemis astronauts using NASA lunar images, examine touchable Moon rock models from their Physics Projects Lab, and create lunar calendars to predict Moon phases for future dates.

Denver Public Library will bring its Bookmobile stocked with Moon, astronomy, space science, and night-sky books for visitors of all ages. Families can browse and check out books during the event, making it easy to keep exploring the Moon and the universe long after the evening ends.

Wings Over the Rockies will lead a hands-on constellation projector activity, where visitors create pinhole constellations in paper cups and project star patterns onto nearby surfaces. After sunset, the activity will transition to red light to help preserve night vision near the telescope area.

Join us on the lawn south of Chamberlin Observatory at 2930 E. Warren Avenue in Denver and celebrate International Observe the Moon Night with fellow sky enthusiasts from across the Denver area.