James Webb Space Telescope
The James Webb Space Telescope is a large infrared space telescope launched in 2021, able to study the chemistry of asteroids and comets.
The James Webb Space Telescope is a space observatory launched on 25 December 2021. It has a gold-coated mirror 6.5 metres across, made of 18 hexagonal segments, and it orbits the Sun about 1.5 million kilometres from Earth, shielded from heat by a sunshield the size of a tennis court.
Webb observes mainly in infrared light, which reveals the chemical fingerprints of water, ices, organic molecules and minerals. It has detected water around a main-belt comet, measured the surfaces of distant objects in the Kuiper Belt, observed the DART impact debris and helped size up near-Earth asteroids. In 2025 it observed the asteroid 2024 YR4, confirming its size of roughly 60 metres.
For meteorite science, Webb's infrared spectra of asteroids can be compared with laboratory spectra of meteorites. This helps work out which kinds of asteroid deliver which kinds of meteorite to Earth.
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Level: Explorer Ages 10 and up