Hubble Space Telescope

The Hubble Space Telescope, a NASA and ESA mission, was launched on April 24, 1990, by the Space Shuttle Discovery. Its 2.4-meter mirror works in visible, ultraviolet and near-infrared light from low Earth orbit. Five shuttle servicing missions, from December 1993 to May 2009, repaired and upgraded it. Science operations are run by STScI, spacecraft operations by NASA Goddard. More than 22,000 peer-reviewed papers had used Hubble data as of 2025.

Flagship instruments

• WFC3: Wide Field Camera 3, visible and near-infrared.
• ACS: Advanced Camera for Surveys.
• COS and STIS: ultraviolet and visible spectrographs.

Recent results

Hubble’s legacy includes the 1995 Hubble Deep Field, about 3,000 galaxies in a patch of “empty” sky, and the 2022 Cepheid measurement of the Hubble constant, 73.04 km/s/Mpc, which pushed the Hubble tension to 5 sigma. Hubble and Gaia data also showed in 2025 that a Milky Way-Andromeda collision is far from certain.

In 2026, globular-cluster studies revealed the Milky Way’s earliest known merger, about 11.8 billion years ago. Two decades of Hubble positions, refined with Webb, found the first stellar-mass black hole in Omega Centauri. Spectra taken in 1999 yielded niobium pointing to a “second-generation” planet, and Hubble tracked a new ten-sided wave at Saturn’s south pole.

What to watch, 2026-2030

• Since mid-2024 Hubble runs in one-gyro mode, at a cost of about 12% in observing efficiency. NASA officials said in June 2024 that its orbit is fine through the mid-2030s.
• Budgets: Congress rejected the proposed FY2026 cuts to NASA science, but the FY2027 request again proposes cutting the Science Mission Directorate by 47%.

Why scientists are converging here

Time is Hubble’s advantage. Several 2026 results relied on archival data or 20-year baselines that no newer telescope can supply, from stellar motions to the Milky Way’s galaxy history.