The $10 billion observatory, launched from a European spaceport in French Guiana on Christmas Day, is the most powerful telescope ever sent into space. It boasts a 21-foot mirror with roughly six times the light-gathering area of the Hubble Space Telescope.
The sunshield plays a vital role for the telescope. It blocks solar radiation and helps keep the telescope ultra-cold — cold enough to pick up infrared light coming from the earliest galaxies to form after the Big Bang, too faint even for Hubble to see.
The telescope is en route to its job site, a spot roughly a million miles from Earth, where it will sit in a solar orbit held stable by the gravitational tug of both the Earth and the Sun. Once it’s fully up and running, it will observe early stars and galaxies and search for biosignatures in the atmospheres of distant planets that could be friendly to life.
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