Check out the giant robot arm assembling NASA’s Webb Telescope

If you thought NASA would leave the assembly of the James Webb Space Telescope to mere humans, you were wrong.

NASA recruited the help of a giant robotic arm at its Goddard Space Flight Center in Maryland to piece together segments of the telescope’s mirrors.

The team uses a robotic arm called the Primary Mirror Alignment and Integration Fixture to lift and lower each of Webb’s 18 primary flight mirror segments to their locations on the telescope structure. Each of the mirrors is made with beryllium, a strategic choice since it can withstand the super cold temperatures of space. Each segment also has a thin gold coating to reflect infrared light. These mirror segments will function in unison once the telescope is in orbit.

“In order for the combination of mirror segments to function as a single mirror they must be placed within a few millimeters of one another, to fraction-of-a-millimeter accuracy. A human operator cannot place the mirrors that accurately, so we developed a robotic system to do the assembly,” said Eric Smith, NASA’s James Webb Space Telescope Program Director.

In order to install each segment with precision, the robotic arm moved in six directions to maneuver over the telescope structure. While one team of engineers maneuvers the robotic arm, another team of engineers simultaneously takes measurements with lasers to ensure each mirror segment is placed, bolted and glued perfectly before moving to the next.

The NASA team uses a laser tracker to indicate reference points and determine where the mirror segments go. The laser is also used to measure points, similar to that of a measuring tape. Then, the engineers can move the mirror to its precise location.

“Instead of using a measuring tape, a laser is used to measure distance very precisely,” said Matthews. “Based off of those measurements a coordinate system is used to place each of the primary mirror segments. The engineers can move the mirror into its precise location on the telescope structure to within the thickness of a piece of paper.”

The James Webb Space Telescope is predicted to be the most powerful telescope ever built and will replace NASA’s Hubble Space Telescope.