The James Webb Space Telescope: Humanity's Deepest Look Into the Universe

On July 12, 2022, NASA released the first full-color images from the James Webb Space Telescope, and the world gasped. The pictures — showing galaxies billions of light-years away in exquisite detail, glowing nebulae where stars are born, and the atmospheric composition of a distant exoplanet — represented the deepest and sharpest infrared images of the universe ever captured. A new era in astronomy had begun.

25 Years in the Making

The James Webb Space Telescope, often called JWST or simply Webb, had been in development since the late 1990s. Originally projected to cost about $1 billion, its final price tag exceeded $10 billion as engineering challenges pushed back the launch date again and again. The telescope was a collaboration between NASA, the European Space Agency, and the Canadian Space Agency, involving thousands of scientists and engineers across more than a dozen countries.

The Launch

Webb launched on December 25, 2021, aboard an Ariane 5 rocket from French Guiana. Over the following month, it underwent one of the most complex deployment sequences in space history: unfolding its tennis-court-sized sunshield, extending its 21-foot gold-coated primary mirror, and traveling to its orbit point roughly one million miles from Earth at the second Lagrange point. Each step had to work perfectly — there was no possibility of a repair mission, unlike with the Hubble Space Telescope.

The First Images

The initial batch of images exceeded expectations. The deep field image of galaxy cluster SMACS 0723 showed thousands of galaxies, some as they appeared over 13 billion years ago, when the universe was in its infancy. The Carina Nebula image revealed towering cosmic cliffs of gas and dust where new stars were forming. The Southern Ring Nebula showed the death of a star in breathtaking detail. And Webb's spectroscopic analysis of exoplanet WASP-96 b detected water vapor in the atmosphere of a planet more than 1,100 light-years away.

A New Window on the Cosmos

Webb was designed to see farther back in time and in greater detail than any previous telescope. Its infrared capabilities allow it to peer through cosmic dust clouds that obscure visible light, observe the formation of the first galaxies after the Big Bang, and study the atmospheres of exoplanets for signs of habitability. In the months and years following its first images, Webb would go on to challenge existing theories about galaxy formation, discover unexpectedly mature galaxies in the early universe, and bring the search for life beyond Earth closer to reality than ever before. For a species that has always looked up at the stars and wondered, Webb was the most powerful eye we had ever built — and what it showed us was more beautiful and more strange than anyone had imagined.