Stargazing

Look through the largest refracting telescope in the world and experience the night sky in a way few people ever do.

Under the Night Sky

As the sun sets, Yerkes shifts. The observatory opens after dark, and the experience becomes quieter, more focused, and centered on the sky above.

Step Into the Dome

Enter the Great Refractor Dome and stand beneath one of the most significant instruments in astronomy.

Look Through the Telescope

When conditions allow, look through the same telescope used by astronomers like Edwin Hubble, Nancy Grace Roman, and Carl Sagan.

Learn as You Go

Guides walk you through what you are seeing, helping connect the experience to the larger story of the night sky.

Stay for the Experience

Each evening unfolds differently depending on the sky, the conditions, and the group, making every visit unique.

Tours & Events

See the Sky at Yerkes

Stargazing experiences are small, limited, and designed to give you time with the telescope and the night sky.

SOLD OUT – Exploring the Night Sky with the 24″ Reflector

This tour is sold out for 2026. This immersive 2-hour experience illuminates the inner-workings of Yerkes after dark.

SOLD OUT – Open Houses

Our Open Houses are sold out for 2026. Check back for more info in 2027! Hands-on discovery for all ages. Interactive demonstrations, themed evenings, and joyful exploration across science, nature, history, and the arts.

SOLD OUT – Exploring the Night Sky

This tour is sold out for 2026. When skies are clear, view the cosmos through the Great Refractor and experience astronomy as it was meant to be.

Astronomy on Tap

Join us at Duesterbeck's Brewing Company (N5543 County Rd O, Elkhorn, WI) on Friday, October 9 at 6 p.m. for this free event.

A One-of-a-Kind Instrument

The Great Refractor

The Great Refractor at Yerkes is the largest refracting telescope ever used for astronomy. At 63 feet long and weighing thousands of pounds, the telescope is so precisely balanced that it can still be moved by hand. Through it, you’ll see light that has traveled millions or even trillions of miles to reach you.

Protect the Night

Discover Why Dark Skies Matter

Dark skies allow us to study the universe, protect the natural rhythms of life, and experience the wonder of the night sky. Learn why natural darkness matters—and how thoughtful choices about outdoor lighting can help preserve it.