Space Telescope Science Institute

The Space Telescope Science Institute (STScI) is a nonprofit astronomical research and science operations center located on the Johns Hopkins University campus in Baltimore, Maryland, founded in 1981 and operated by the Association of Universities for Research in Astronomy (AURA) under contract to NASA. STScI is NASA's primary center for managing the science programs of optical and near-infrared space telescopes — a role that encompasses the Hubble Space Telescope (operational since 1990) and the James Webb Space Telescope (launched December 2021, first science images July 2022).

Hubble's science operations from STScI have produced over 1.5 million observations supporting more than 21,000 peer-reviewed scientific publications — among the most productive instruments in the history of astronomy. Key discoveries include the precise measurement of the Hubble Constant (triggering the Hubble Tension controversy), the acceleration of the universe's expansion (Nobel Prize 2011), characterization of supermassive black hole demographics, and the deep field images revealing the universe at cosmic dawn. STScI manages the annual time allocation competition receiving approximately 1,000 proposals for roughly 100 accepted programs, and maintains the Hubble Legacy Archive.

JWST — sited at the Sun-Earth L2 Lagrange point 1.5 million km away — represents STScI's most complex operational challenge: a $10B observatory performing infrared astronomy at 6K operating temperature with no servicing mission possible. STScI manages proposal selection (oversubscribed 8:1 in early cycles), science data pipeline processing, and the MAST archive (Mikulski Archive for Space Telescopes) hosting Hubble, JWST, Kepler/K2, TESS, GALEX, and High Level Science Products.

The Nancy Grace Roman Space Telescope (planned 2027 launch), with its 0.28 sq degree field of view — 100× Hubble's — is next in STScI's portfolio. Staff of approximately 700 spans astronomers, software engineers, archive specialists, and mission support personnel. Parallel infrared space telescope science operations are managed by IPAC at Caltech (Spitzer, WISE, Euclid).