24-in Clark Refractor 125th Anniversary

The historic 24” Clark Refractor is turning 125 years old this year, and we’re celebrating in a big way!

From May 15th to December 31st, we’re hosting a series of events that highlight the past, present, and future of Mars Hill’s oldest and most storied telescope. During the celebration, our regular campus tours and telescope viewing sessions will feature extra historical tidbits about the telescopes of Lowell and the Clark’s influence on their designs. Tune in each month for live streams that dive into the Clark’s history and its notable place in pop culture, plus live views of the celestial objects it has been used to study over the years. July 23rd was our First Light Celebration, which featured a live virtual event!

More details and live streams to be announced!

Experience the Clark Refractor

Explore this historic telescope for yourself during one of our guided tours.

Live Streams

Upcoming: October 21 @ 8pm PDT

Clark 125th Anniversary | Neptune and the Outer Solar System

Join us for a Livestream to celebrate the historic Clark Refractor’s 125th anniversary! We will be streaming live from the Clark Dome from 8:00-8:45pm PDT.

  • Lowell Historian Kevin Schindler will discuss the unique structure of the Clark dome, including its original construction in an employee’s back yard, canvas covering, and more.
  • Lowell educators at the Clark Refractor will share live views of the planet Neptune, which Percival Lowell and EC Slipher studied more than a century ago.
  • Lowell Astronomer Dr. Jennifer Hanley will join Schindler to discuss this early research of Neptune and the outer solar system and its relevance to her modern-day studies of Titan and other icy bodies. 

This event was made possible by our Lowell Observatory members and donors. To help our nonprofit continue to create amazing educational opportunities related to science and space, check out our membership offerings.

Watch on YouTube

Streamed Live September 16

Clark 125th Anniversary | Celebrating Saturn

Join us for a Livestream celebration of the 125th anniversary of the historic Clark Refractor! The program starts at 9:30pm and includes:

  • Lowell Historian Kevin Schindler will discuss the evolution of the Clark Refractor’s tracking system, from an old clock drive to Rube Goldberg-like governor to modern stepper motors.
  • Lowell educators at the Clark Refractor will share live views of the planet Saturn, which Percival Lowell and EC Slipher studied more than a century ago.
  • Lowell Astronomer Dr. Amanda Bosh will join Schindler to discuss this historic research of Saturn and how it compares to her modern-day studies.
Watch on YouTube

Streamed Live August 19

Clark 125th Anniversary | Imaging Jupiter

Join us for a Livestream celebration of the 125th anniversary of the historic Clark Refractor! The program runs from 9:30-10:15 pm PDT and includes:

  • Lowell Historian Kevin Schindler will discuss historic instruments used on the Clark for imaging: cameras, spectrograph, comet eyepiece, etc.
  • Lowell educators at the Clark Refractor will share live views of the planet Jupiter, which Percival Lowell and EC Slipher imaged more than a century ago.
  • Lowell Astronomer Dr. Phil Massey will join Schindler to compare these historic techniques to those of today, with special attention on the Lowell Discovery Telescope’s Large Monolithic Imager.
Watch on YouTube

Streamed Live July 23

Clark 125th Anniversary | First Light

On this day in 1896, Lowell Observatory’s 24-inch Clark Refractor saw first light. Thus began the life of one of the world’s most storied telescopes. Join Lowell astronomer Stephen Levine and historian Kevin Schindler as they recount the events leading up to the Clark’s first light and then compare this process to that followed in developing today’s Lowell Discovery Telescope.

Watch on YouTube

Streamed Live July 15

Clark 125th Anniversary | Binary Star Research

Join us for a livestream celebration of the 125th anniversary of the historic Clark Refractor! The program runs from 9:30-10:15 pm PDT and includes:

Lowell Historian Kevin Schindler will share the sometimes quirky observing chairs that astronomers used through the years.

Lowell educators at the Clark Refractor will share live views of colorful Albireo, a double star typical of those studied through the years by the enigmatic TJJ See, Jim Christy, and Otto Franz.

Lowell Astronomer Dr. Lisa Prato will join Schindler to discuss the importance of this early double star work and its relevance to her research today.

Watch on YouTube

Streamed Live June 17

Clark 125th Anniversary | Beta Scorpii

Join us for a live stream celebration of the 125th anniversary of the historic Clark Refractor! The program runs from 9:30-10:15 pm PDT and includes: Lowell Historian Kevin Schindler will discuss ways the Clark dome has been rotated through the years, including on pontoons in a trough of saltwater! Lowell educators at the Clark Refractor will share live views of the star Beta Scorpii, the object that Dr. VM Slipher studied more than a century ago in proving the existence of interstellar gas. Lowell Astronomer Dr. Kyler Kuehn will join Schindler to discuss the relevance of Slipher’s discoveries to modern-day research, particularly Kuehn’s work with the Dark Energy Survey and the Southern Stellar Stream Spectroscopic Survey.

Watch on YouTube

Streamed Live May 15

National Astronomy Day

Join us for a livestream in celebration of National Astronomy Day and the 125th anniversary of the historic Clark Telescope! Starting at 8:30pm PDT, join Lowell educators at the Clark Refractor for live views of the Sombrero Galaxy, the first object that was observed–by Vesto Slipher–to have been redshifted. Lowell astronomer Deidre Hunter will discuss the Sombrero’s importance to Slipher’s research on what we know today as galaxies, her own modern-day galaxy research, and how she got interested in astronomy. You’ll also hear all about the Clark’s fascinating history and its place in popular culture.

Watch on YouTube

Commemorate the Clark Refractor’s 125th anniversary with merch from our Starry Skies Shop