Entry No. 210 — the Denver file — filed under: after-dark

Sommers-Bausch Observatory Open House Nights

On CU Boulder's main campus next to Fiske Planetarium, this working teaching observatory throws open its rooftop observing deck on clear Friday nights, free of charge. You queue at the eyepiece of two 20-inch PlaneWave telescopes aimed at the Moon, planets, nebulae and galaxies, with live camera feeds on big screens for anyone who can't manage the step ladder. Because they only open under clear skies, they post a go/no-go status on Facebook and Instagram and by phone (303-492-2020) in the hour before start time. Sessions run loose, one to three hours, depending on the weather and the crowd.

The move: Check the clear-sky status, then spend a free Friday night trading turns at the 20-inch telescope on the open rooftop deck.

📍 Before you go Friday-night open houses only happen on clear nights while CU is in session; summer start is 9pm. Call after 7:45pm for status. Free.

• 📍 Boulder
• 💸 $
• ⚡ Low-key
• 🌗 Outdoors

Where: 2010 Colorado Ave, Boulder, CO 80305

Hours: Added 2026-06-23 — confirm current hours before you go.

⚠ Seasonal or scheduled — always check before you go.

Plan a visit & invite your people →

Proof: source 1 · source 2 · source 3

last checked: 2026-06-23