Entry No. 24 — the Charleston file — filed under: observatory
College of Charleston Observatory
A working 24-inch research telescope lives inside a dome on the roof of a downtown college science building, and a few times a semester the Physics & Astronomy department throws the doors open, free, so anyone can climb up onto 'Rita's astronomy deck' and look through it alongside a row of smaller portable scopes.
The story
Most people walking past 58 Coming Street see a standard campus facility—the Rita Liddy Hollings Science Center, which underwent a four-year, $65 million renovation. But up on the roof, housed inside a white dome, sits a 24-inch PlaneWave CDK research telescope, one of the most powerful optical instruments in South Carolina. While physics students use it during the week to study deep-space phenomena, the department opens the rooftop to the public a few times a semester for free.
It is an unadvertised perk in a city far better known for architectural heritage tours than astrophysics. You won't see billboards around town; instead, word spreads via departmental calendar postings. You take the elevator up to the third floor, follow paper signs taped to the walls pointing toward the stairwell, and step out onto 'Rita's astronomy deck,' where faculty and students set up portable 8-inch telescopes alongside the main observatory dome.
What it's like
You will enter through the Coming Street doors and head up to the third floor, where physics students often run hands-on science demos in the lab classrooms before guiding you to the roof. The atmosphere on the observation deck is casual and family-friendly, with small queues forming around portable scopes pointed at Jupiter, Saturn, or the moon. If you want to go inside the dome and peer through the primary 24-inch scope, you must claim a free timed ticket online ahead of time; deck access and smaller scopes require no ticket at all. Closed-toe shoes are strictly required on the observation deck, and severe clouds or rain will cancel the roof viewing.
The move: Grab a free ticket ahead of the open-house date, climb to the roof deck at dusk, and queue for a turn at the 24-inch scope between the smaller telescopes scattered around it.
- 📍 Downtown Charleston (College of Charleston campus)
- 💸 $
- ⚡ Low-key
- 🌗 Outdoors
Where: 58 Coming St, Charleston, SC 29424 (Rita Hollings Science Center rooftop)
Hours: Added 2026-07-20 — confirm current hours before you go.
⚠ Seasonal or scheduled — always check before you go.
Pair it with
- Halsey Institute of Contemporary Art — Located right on campus just 0.1 miles away, this free non-collecting contemporary art museum makes an easy warm-up stop before heading up to the science center roof at dusk.
- Lowcountry Stargazers — Astronomy in the Park — If you want another night under the stars, connect with Charleston's amateur astronomy community at their weekly Wednesday setup along the Ashley River.
- The Charleston Museum — Early Days Gallery — Walk four blocks east to inspect 18th- and 19th-century cabinet-of-curiosity specimens before shifting your perspective to deep space from the campus dome.
Good to know
Is the observatory open house really free?
Yes, admission is completely free. However, if you want to enter the dome to look through the main 24-inch telescope, you must reserve a free ticket online in advance due to strict space limits inside the dome.
What is the dress code for visiting the roof?
Closed-toe shoes are mandatory on the observation deck. You will not be permitted onto the roof in sandals or flip-flops.
How often do public open houses take place?
The Physics & Astronomy department hosts open house nights a few times per semester, typically scheduled around clear moon phases or celestial events.
What happens if weather conditions are bad?
Telescope viewing requires clear skies. Rain, heavy cloud coverage, or campus closures will cancel the rooftop portion, so check the observatory's website or social media pages before heading over.
Plan a visit & invite your people →
Further reading: chartasg.wixsite.com · Facebook · postandcourier.com
last checked: 2026-07-20