A year with JWST

To celebrate JWST’s first year of operation, Jenny Winder takes a look at some of the landmark scientific discoveries it has made over the last 12 months

- Jenny Winder

With a primary mirror measuring 6.6m across made from 18 gold-coated segments, the James Webb Space Telescope (JWST) is a beautiful instrument in its own right. But stunning as this technological marvel might be, it's nothing compared to the remarkable data it has unearthed over the last year.

JWST launched on 25 December 2021, reaching its operational orbit at the second Lagrange point, 1.5 million kilometres from Earth, a month later. After a few more months calibrating its instruments, it was finally ready to turn its gaze on the Universe.

JWST has been tasked with investigating four main science goals: the early Universe and the first galaxies; the growth and evolution of galaxies over time; the lifecycle of stars; and the study of other worlds.

The new telescope is uniquely suited to investigating these goals as it observes infrared wavelengths. This light can pass through clouds of dust and gas, and reveal warm objects that do not shine in visible wavelengths, meaning it can peer into corners of the Universe previously hidden from view.

JWST began returning its first remarkable scientific findings in July 2022. Here we look back at some of the milestones it has achieved during its first year.

The first galaxies in the Universe

JWST’s Advanced Deep Extragalactic Survey spies on galaxies in their infancy

One key part of JWST's mission will be to use its infrared eyes to peer through the dust and gas to the earliest eras of the Universe. Here it will help discover how the first stars and galaxies formed, as well as uncover fresh evidence for dark matter.