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Space telescope data has underpinned 1.5 million+ scientific papers since 1990.
| Attribute | James Webb Space Telescope (JWST) NASA/ESA/CSA · 🇺🇸 Active · Last updated 2026-06-01Trust: Agency-primaryⓘ Last verified Remove × | ||
|---|---|---|---|
| Agency | NASA | NASA | NASA/ESA/CSA |
| Status | Retired | Retired | Active |
| Wavelength band | optical | infrared | infrared |
| Launch year | 2009 – 2018 | 2003 – 2020 | 2021 |
| Orbit | Earth-trailing heliocentric orbit | Earth-trailing heliocentric orbit | Sun-Earth L2 point (~1.5 million km from Earth) |
| Mirror / aperture | 1.4 mas of [1] | 0.85 mas of [1] | 6.5 mas of [1]18 gold-coated beryllium hexagonal segments ↑ Largest |
| Mass | 1,052 kgas of [1] | 950 kgas of [1] | 6,200 kgas of [1]Includes 2,447 kg for the primary mirror assembly ↑ Heaviest |
| Wavelength range | 0.43–0.89 μm (optical) | 3.6–160 μm (mid-to-far infrared) | 0.6–28.5 μm (optical red through mid-IR) |
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| Summary | The mission that proved planets are abundant throughout the galaxy. Kepler monitored 150,000+ stars continuously for 4 years, finding that most stars host planets. A reaction wheel failure in 2013 ended the primary mission; the repurposed K2 mission (2014–2018) found 1,000+ additional planets before fuel ran out. | NASA's infrared Great Observatory, operating 2003–2020. Best known for discovering the TRAPPIST-1 system of 7 Earth-sized planets, including 3 in the habitable zone (with ground telescopes). Ran out of cryogen in 2009 but continued 'warm mission' until retirement in January 2020. | The most powerful space telescope ever launched. Operating at -233°C at the L2 point, JWST can observe the universe's first light from ~100 million years after the Big Bang. Its first full-color images, released July 2022, immediately set records for the most distant galaxies observed. |
All 9 major space telescopes with primary-source citations from NASA, ESA, STScI, and JPL. Pure URL state — bookmark or share the link and the comparison reproduces exactly.