Mirrors on NASA’s ‘James Webb Telescope’ Receive Gold Coating

NASA’s next generation Hubble, the James Webb telescope, recently received a high-class coating – 0.12 ounces of gold – on each of six important mirror segments. The microscopic layer of gold will protect the beryllium surface from radiation in space, the extreme cold, and other stresses related to long-term space travel.

The James Webb telescope is set to become a primary tool for scientists looking deep into the cosmos. A system of 21 mirrors works together on the telescope and will allow scientists to observe some of the most distant objects in the universe while the telescope flies in high orbit around Earth. Scientists hope to use the telescope to find images of the first galaxies ever formed and to take a close look at planets around distant stars.

The gold coating was applied by Quantum Coatings, Inc., a Moorestown, NJ, coating company. Quantum used a unique method to create the thin coating layer. The gold was heated up to its liquid point (more than 2,500 degrees Fahrenheit) and was allowed to evaporate onto the telescope’s beryllium mirrors. The coating that resulted was a mere 120 nanometers (about 200 times thinner than human hair) and almost perfectly even.

Now that the six main mirrors have been coated, they’re on the move to Boulder, CO where they’ll be fitted with actuators to allow scientists to adjust the mirrors in orbit. The telescope is the most expensive ever built at $8.7 billion and is a joint project between NASA, the European Space Agency and the Canadian Space Agency. You can read more about the telescope on NASA’s James Webb page.