After nearly a full month in space, the James Webb Space Telescope, also known as JWST or Webb, is nearly at the end of its deployment work.

"Just in from the @NASAWebb team: All 18 primary mirror segments and the secondary mirror are now fully deployed!" NASA Administrator Bill Nelson wrote in a tweet posted on Wednesday (Jan. 19).

Live updates: NASA's James Webb Space Telescope mission.

Related: How the James Webb Space Telescope works in pictures.

JWST's golden primary mirror includes 18 individual hexagonal segments, each controlled by seven actuators that allow precise movements.

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