Explore the Campus

Pluto Discovery Dome

Discover the historic Pluto Astrograph, built to aid in the search for ‘Planet X,’ and eventually used by Clyde Tombaugh to take the photographic plates used to discover Pluto in February of 1930.

Adults

Families

Included with Admission

Great For

Adults
Families

Built in 1928-1929 specifically for the search for “Planet X,” the Pluto Discovery Telescope at Lowell Observatory is one of the most famous telescopes in American astronomical history. This historic instrument, originally designed to confirm Percival Lowell’s hypothesis of a ninth planet, played a pivotal role in the groundbreaking discovery of Pluto in 1930. Today, the telescope stands as a testament to scientific perseverance and exploration.

VIEW A PRICELESS ASTRONOMY ARTIFACT
- Built in 1928-1929 specifically for the search for “Planet X,” the Pluto Discovery Telescope at Lowell Observatory is one of the most famous telescopes in American astronomical history.
HEAR PLUTO’S STORY
- During open house hours, a Lowell educator will be present to answer questions and share details of the process that led to Pluto’s discovery in 1930.
SELF-GUIDED LEARNING
- Explore the very building where groundbreaking astronomy history was made at your own pace.

*Please note, the Pluto Dome has stairs that lead to the Astrograph and is not ADA accessible.

Pluto Discovery Dome

Experiences Here

Whether you're here to learn from us or dive into groundbreaking research, you're in for an unforgettable adventure! From interactive exhibits to awe-inspiring stargazing nights, every corner of the Lowell Observatory is a gateway to discovery.

Open House

Historic Pluto Astrograph Open House

Varies

Included

Pluto Discovery Dome

Step Inside the Room Where Pluto Was Discovered in 1930.

Daily except Tuesdays

Schedule subject to change, check with Visitor Services for current times.

The Search for Planet X

Take a self-guided tour through the dome that houses the 13-inch Lawrence Lowell Astrograph, the historic instrument used by observatory assistant Clyde Tombaugh to discover Pluto in 1930.

Black-and-white photo of Clyde Tombaugh standing in the doorway of the Pluto Discovery Dome at Lowell Observatory. He holds a large glass photographic plate used for capturing images of the night sky, wearing a suit and tie, symbolizing the era of early astronomical discovery.

Historic Astrophotography

See how Tombaugh captured wide-field images using 14″ x 17″ glass photographic plates, ultimately revealing Pluto’s location among distant stars at the edge of our solar system.

Black-and-white photo of astronomer Clyde Tombaugh examining glass photographic plates using a Zeiss blink comparator at Lowell Observatory. He peers through the eyepiece of the machine, hand on the control lever, comparing star fields that led to the discovery of Pluto in 1930.

Pluto Discovery Story

Discover the incredible story of persistence, skill, and groundbreaking science that led to Pluto’s discovery during an informal Q and A session with a Lowell educator.

ChatGPT said: Black-and-white photo of Clyde Tombaugh standing outdoors beside his homemade Newtonian telescope. He rests one hand on the long cylindrical telescope tube, wearing a white shirt, tie, and glasses, gazing thoughtfully at the instrument that helped launch his career in astronomy.

Pluto Discovery Dome

Upcoming Events

Whether you're here to learn from us or dive into groundbreaking research, you're in for an unforgettable adventure! From interactive exhibits to awe-inspiring stargazing nights, every corner of the Lowell Observatory is a gateway to discovery.