Pick up to 4 telescopes to compare side-by-side. State lives in the URL — share the link and the comparison loads exactly as you left it.
Space telescope data has underpinned 1.5 million+ scientific papers since 1990.
| Attribute | Chandra X-ray Observatory (CXO) NASA · 🇺🇸 Active · Last updated 2026-06-01Trust: Agency-primaryⓘ Last verified Remove × | TESS (Transiting Exoplanet Survey Satellite) NASA · 🇺🇸 Active · Last updated 2026-06-01Trust: Agency-primaryⓘ Last verified Remove × | |
|---|---|---|---|
| Agency | NASA | ESA | NASA |
| Status | Active | Active | Active |
| Wavelength band | x-ray | multi | optical |
| Launch year | 1999 | 2023 | 2018 |
| Orbit | Highly elliptical (perigee 10,000 km / apogee 140,000 km) | Sun-Earth L2 point | High Earth orbit (P/2 lunar resonance orbit) |
| Mirror / aperture | 1.2 mas of [1]Four pairs of nested grazing-incidence mirrors; effective aperture 0.04 m² ↑ Largest | 1.2 mas of [1] ↑ Largest | — |
| Mass | 4,800 kgas of [1]Including HRMA mirror assembly ↑ Heaviest | 2,160 kgas of [1] | 362 kgas of [1] |
| Wavelength range | 0.1–10 keV (soft to medium X-ray) | 0.55–2.02 μm (optical VIS + near-IR NISP) | 0.6–1.0 μm (red optical) |
| Key missions |
|
|
|
| Summary | NASA's flagship X-ray telescope and one of the Great Observatories. Chandra's angular resolution is 100× better than previous X-ray telescopes, enabling detailed imaging of supernovae remnants, galaxy clusters, and the region around supermassive black holes. Still operating after 25+ years despite being designed for a 5-year mission. | ESA's dark energy explorer, launched July 1, 2023. Euclid will map the 3D distribution of ~1.5 billion galaxies across a third of the sky over 6 years, measuring dark energy and dark matter with unprecedented precision. Its first science-quality images, released February 2024, demonstrated exceptional optics. | NASA's all-sky transit photometry survey, successor to Kepler. TESS monitors nearly the entire sky in 27-day sectors using four wide-field cameras, targeting the 200,000 brightest stars nearest to Earth. Its targets are close enough for atmospheric follow-up by ground telescopes and JWST. |
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.