The Hubble Space Telescope

Astrophysicist Lyman Spitzer published a paper arguing that a telescope above Earth's atmosphere could observe the universe without atmospheric distortion. The idea, dismissed as impractical at the time, became the seed of the eventual Large Space Telescope project four decades later.

Location: USA

After years of lobbying by astronomers, the US Congress approved funding for what became the Hubble Space Telescope, with the European Space Agency joining as a partner. Construction was assigned to Perkin-Elmer for optics and Lockheed for the spacecraft.

Location: Washington, D.C., USA

The Space Shuttle Discovery deployed the Hubble Space Telescope into orbit about 540 kilometers (335 miles) above Earth after years of delays, including the 1986 Challenger disaster. It was named for astronomer Edwin Hubble, whose work established the expansion of the universe.

Location: Kennedy Space Center, Florida, USA

Weeks after launch, engineers found that Hubble's 2.4-meter primary mirror had been ground to the wrong shape — spherical aberration that blurred its images. The flaw became a public controversy over NASA's quality control, and late-night comedy made the telescope a national punchline.

Location: USA

Shuttle Endeavour's STS-61 mission installed corrective optics — the COSTAR system and a new Wide Field camera — in a series of spacewalks. The fix restored the telescope's intended vision, and the first sharp images redeemed the project and NASA's reputation.

Location: Low Earth orbit

Hubble's Deep Field images — long exposures of tiny "empty" patches of sky — revealed thousands of galaxies from the early universe. Combined with distance measurements of variable stars, Hubble data pinned the universe's age at roughly 13.8 billion years and pinned down the expansion rate debate.

Location: Space Telescope Science Institute, Baltimore, USA

Observations from Hubble and ground telescopes of distant supernovae showed that the universe's expansion is accelerating, implying the existence of dark energy. The discovery, which overturned assumptions about cosmic slowing, earned the 2011 Nobel Prize in Physics for the teams' leaders.

Location: USA

Hubble captured the first visible-light image of a planet orbiting another star, Fomalhaut b. Exoplanets had been detected indirectly since 1995, but direct imaging opened a new window on worlds beyond the solar system.

Location: Space Telescope Science Institute, Baltimore, USA

Shuttle Atlantis's STS-125 mission — reinstated after cancellation following the 2003 Columbia disaster — installed the Wide Field Camera 3 and repaired the Advanced Camera for Surveys during five spacewalks. It was the fifth and last servicing mission, leaving Hubble at peak capability for the coming decades.

Location: Low Earth orbit

Hubble marked 30 years in orbit, having made more than a million observations and fueled over 20,000 published papers. Expected to operate into the late 2020s alongside the James Webb Space Telescope, it remained the most productive observatory in the history of astronomy.

Location: Low Earth orbit

In the first coordinated Hubble-Webb study of trans-Neptunian objects, astronomers simultaneously observed a patch of sky in visible and infrared light and characterized 27 newly discovered bodies, including some of the smallest and faintest ever directly detected. The smallest measured about 5 kilometers across, and the survey found fewer tiny objects than some planet-formation models predicted; the similar colors of small and large objects suggested that many surfaces retained primordial compositions rather than being extensively altered by collisions. The result demonstrated how Hubble's visible-light sensitivity and Webb's infrared measurements could jointly probe objects that neither observatory could fully characterize alone.

A peer-reviewed study published September 15 reported that deep Hubble observations of the starburst galaxy Messier 82, or M82, resolved more than 2,000 narrow filaments in its southern galactic wind. A typical filament measured about 31 light-years long and 17 light-years wide. The team found that ultraviolet radiation from the central burst of star formation illuminated the bright filaments, while shocks and other heating processes became more important in the fainter, more diffuse gas. The observations provide a detailed benchmark for models of how gas survives, escapes galaxies, and carries newly formed elements into intergalactic space; the authors cautioned that smaller structures may be destroyed or too faint to detect, so the result constrains rather than settles the underlying physics.

On October 5, 2026, astronomers announced the first candidate second-generation planet ever identified: a Jupiter-sized world that may have formed not from a star's birth material but from the debris ejected when a star died. The study, published in Nature Astronomy, emerged from a reanalysis of Hubble archival observations of the white dwarf HS 0209+0832 first taken in 1999, which contained roughly 100 chemical features that went unidentified for more than a quarter of a century. Lead author Jamie Williams, a doctoral candidate at the University of Warwick, matched many of the mystery spectral lines to the element niobium using an updated chemical database, and the team confirmed the signature with data from NASA's retired FUSE observatory. Because niobium and other elements heavier than iron are forged only in the brief, extreme conditions inside dying stars rather than by ordinary fusion, the abundance points to a planet assembled from a star's cast-off innards rather than its birth disk. NASA's TESS satellite independently recorded periodic brightness variations over four months, indicating a gas giant orbiting about 6 million kilometers from the remnant and slowly losing its atmosphere to the still-hot star. Planets had been detected orbiting white dwarfs before, but the researchers described this as the first candidate bearing the chemical hallmarks of a planet born from stellar death, and cautioned that the interpretation still needs to be tested by further observations.