Sizes refer to diameter of lens or mirror

Princeton University Archives

Professor Stephen Alexander observes solar eclipses with Munich-made telescope, second-largest in United States.

Observatory of Instruction
Observatory of Instruction
Princeton University Archives

Professor Charles Young teaches with telescope (right, refurbished and now hanging in Peyton Hall) in Observatory of Instruction (on site of today’s Robertson Hall).

Halsted Observatory
Halsted Observatory
Princeton University Archives

Halsted Observatory (on site of today’s Joline Hall) has largest ­telescope in the hemisphere, except for U.S. Naval Observatory. Cast in Paris, the lenses were exhibited at the Centennial Exhibition, Philadelphia.

FitzRandolph Observatory
FitzRandolph Observatory
Frank Wojciechowski

Halsted Observatory demolished, replaced by FitzRandolph Observatory near Palmer Stadium; telescope rebuilt using the 1882 lenses.

Lyman Spitzer *38, left, and Martin Schwarzschild
Lyman Spitzer *38, left, and Martin Schwarzschild
Princeton University Archives
Professors Lyman Spitzer *38 and Martin Schwarzschild make regular trips to use this huge California ­telescope.
Model of Stratoscope II, left; Stratoscope I and NASA balloon
Model of Stratoscope II, left; Stratoscope I and NASA balloon
Smithsonian NASM (left); U.S. Navy

Professor Martin Schwarzschild’s ­telescope floats beneath giant NASA ­balloon; Perkin-Elmer quartz mirror can distinguish one toadstool from two at 1,000 miles.  Model is on display at the National Air and Space Museum in Washington, D.C.

Goddard Space Flight Center
Professor Lyman Spitzer *38 and his Princeton team design ultraviolet telescope on NASA satellite, a ­precursor to Hubble.
Physics professor David Wilkinson plays key role in NASA satellite that maps microwave radiation from the Big Bang.
NASA
Multibillion-dollar NASA project fulfills Lyman Spitzer’s 1946 vision of “extra-terrestrial ­observatories.”
Apache Point Observatory
Apache Point Observatory
Fermilab

Professor James Gunn designs a telescope at Apache Point in New Mexico that creates the most elaborate map in history.

David Spergel ’82, left, and Lyman Page
David Spergel ’82, left, and Lyman Page
Courtesy Lou Tucciarone ’79
Professors David Spergel ’82, left, and Lyman Page create NASA satellite that follows up on COBE. It maps microwave background fully and revolutionizes cosmology.
Subaru Telescope domes on the summit of Mauna Kea.
Subaru Telescope domes on the summit of Mauna Kea.
© Subaru Telescope/National Astronomical Observatory of Japan
Princeton begins 10-year partnership with National Astronomical Observatory of Japan to use one of the world’s largest telescopes, at the Mauna Kea volcano in Hawaii.