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Space telescope data has underpinned 1.5 million+ scientific papers since 1990.
| Attribute | Fermi Gamma-ray Space Telescope NASA/DOE/international · 🇺🇸 Active · Last updated 2026-06-01Trust: Agency-primaryⓘ Last verified Remove × | ||
|---|---|---|---|
| Agency | NASA | NASA | NASA/DOE/international |
| Status | Retired | In Development | Active |
| Wavelength band | infrared | infrared | gamma-ray |
| Launch year | 2003 – 2020 | 2027 | 2008 |
| Orbit | Earth-trailing heliocentric orbit | Sun-Earth L2 point | Low Earth Orbit (LEO) ~550 km, 25.6° inclination |
| Mirror / aperture | 0.85 mas of [1] | 2.4 mas of [1]Same aperture as Hubble but 100× wider field of view ↑ Largest | — |
| Mass | 950 kgas of [1] | ~4,200 kgas of [1]Estimated; uses repurposed NRO mirror donated to NASA | 4,303 kgas of [1] ↑ Heaviest |
| Wavelength range | 3.6–160 μm (mid-to-far infrared) | 0.48–2.3 μm (optical + NIR) | 20 MeV – 300 GeV (LAT); 8 keV – 40 MeV (GBM) |
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| Summary | 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. | NASA's next flagship astronomy mission. Roman's 300-megapixel Wide Field Instrument (WFI) has Hubble-equivalent resolution but covers 0.28 square degrees per pointing — 100× wider than Hubble. Its 5-year primary mission will census dark matter, dark energy, and exoplanet populations across the Milky Way. | The most sensitive gamma-ray telescope ever flown. Fermi's Large Area Telescope (LAT) has detected over 6,000 gamma-ray sources — pulsars, blazars, gamma-ray bursts, and potentially dark matter annihilation signals. Its GBM instrument records ~300 gamma-ray bursts per year. |
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.