On February 3, NASA announced the first particles of light have made their way through the entire James Webb Space telescope. This was confirmed by the Near Infrared Camera, one of the science instruments onboard. First Light’ is an important milestone for any telescope. However no image to show yet. ‘This is the very beginning of the process, but so far the initial results match expectations and simulations,’ NASA explained. Webb’s mirrors will progressively focus in on HD 84406, a star similar in size and brightness to our Sun that makes up the Big Dipper constellation. For the time being, the 18 hexagonal elements of the primary mirror are working as 18 separate telescopes. To bring each segment into the right position to work together perfectly, the team need to tweak their individual position. Each mirror’s direction can be adjusted in the very tiniest of increments, each equal to a ten-thousandth of the width of a human hair.
The full alignment of telescope’s mirrors will take about three months. Webb needs to be very cold. In about five more months, after cooling, Webb will begin an ambitious science program covering all aspects of astrophysics. The first images expected from the JWST will likely be blurry as engineers gradually fine tune the telescope. Webb will be able to peer deep into dust clouds where exoplanets are forming. Webb may also be able to assist with dating stars in globular clusters. That would help astronomers with understanding stellar ages and the evolution of the universe at large.