The James Webb telescope will soon replace the Hubble Space Telescope in orbit around the Earth, bringing our galaxy into focus. And exploring the origins of the universe. These incredible, huge mirrors will make those images happen.
A joint project of NASA, the European Space Agency, and the Canadian Space Agency, Webb will launch in 2014. A big part of its mission will be to look at objects at the very edges of the universe, in order to gather more data about the Big Bang.
According to NASA:
To see such far-off and faint objects, Webb needs a large mirror. A telescope's sensitivity, or how much detail it can see, is directly related to the size of the mirror area that collects light from the objects being observed. A larger area collects more light, just like a larger bucket collects more water in a rain shower than a small one.
Webb Telescope's scientists and engineers determined that a primary mirror 6.5 meters (21 feet 4 inches) across is what was needed to measure the light from these distant galaxies.
Just as a point of comparison, the Hubble mirrors are 2.4 meters.
The Webb Telescope team decided to make the mirror segments from beryllium, which is both strong and light . . . The Webb Telescope team also decided to build the mirror in segments, on a structure which will fold up, like the leaves of a drop-leaf table, so that it can fit into a rocket. The mirror would then unfold after launch. Each of the 18 hexagonal-shaped mirror segments is 1.3 meters (4.26 feet) in diameter.
You can see some of these hexagonal segments in these images.
Learn more at NASA.