James Webb Telescope Launched
The most powerful space telescope ever built launched from French Guiana
December 25, 2021
The Telescope Worth Waiting For
The James Webb Space Telescope launched on December 25, 2021, after more than 20 years of development and a budget that grew from $500 million to $10 billion. It is the most powerful space telescope ever built — roughly 100 times more sensitive than the Hubble. Webb was designed to see the very first stars and galaxies that formed after the Big Bang, over 13 billion years ago.
Getting Into Position
Webb had to fold itself like origami to fit inside the rocket, then unfold its 18 gold-plated mirror segments and a tennis-court-sized sunshield after launch. It traveled to a point called L2, 1.5 million kilometers from Earth — four times farther than the Moon — where it sits in permanent shadow, kept cold enough to detect faint infrared light from the earliest universe. The unfolding process had over 300 possible single points of failure.
What It Has Shown Us
Webb's first images, released in July 2022, showed galaxies more than 13 billion light-years away in stunning detail. It has detected water vapor in the atmosphere of exoplanets, analyzed the chemical composition of distant worlds, and already challenged some existing theories about how galaxies form. Scientists expect Webb to operate for at least 20 years, reshaping our understanding of the universe more than any instrument before it.