James Webb Space Telescope (NASA/ESA/CSA, 2021)

After 25 years of development and a budget that grew from $500 million to $10 billion, the James Webb Space Telescope launched on December 25, 2021 and unfolded its 6.5-meter golden mirror flawlessly at the L2 Lagrange point, 1.5 million km from Earth. Its first science images, released in July 2022, were the deepest and sharpest infrared images of the universe ever taken. Webb detected galaxy candidates from just 300 million years after the Big Bang — far earlier than models predicted — forcing a revision of galaxy formation theories. Its instruments have characterized exoplanet atmospheres in unprecedented detail, detecting carbon dioxide in the atmosphere of WASP-39 b in 2022. Webb is expected to operate for at least 20 years.