The mirrors of the James Webb Space Telescope are coated with a fine film of vaporized gold to improve reflection of infrared light.
Excess Heat Could Damage Sensitive Instruments
NASA engineers are also tapping on the properties of gold to redirect excess heat from the sensitive instruments of the telescope.
Webb has a structure located behind its primary mirror. It is known as the integrated science instrument module (ISIM) and houses the telescope's four main instruments that will detect light from planets orbiting other stars, distant stars, and galaxies. The unit is like a car's chassis that supports the vehicle's engine and other components.
Excess heat could damage the sensitive instruments, so most of the electronics used for providing power and operating the instruments are placed in a compartment below the ISIM where special baffles can direct the heat away.
The baffles work by acting as mirrors to reflect infrared radiation away in a specific direction.
The gold baffles will direct the heat produced by the instrument electronics away from any cold areas of the infrared telescope and safely into space.
"Gold has a very high reflectivity in the infrared spectrum range, so it is ideal for directing heat," said Matthew Stephens, from NASA's Goddard Space Flight Center.
NASA Engineers Reinstalling Gold Baffles
As NASA scientists and engineers continue to test the observatory, the gold baffles had to be removed, stored in a clean environment and covered by clear plastic sheets to protect them from contamination.
NASA said on Tuesday that engineers are now installing the gold baffles. The space agency said that the engineers need to reinstall the baffles before the telescope's science payload and spacecraft elements are integrated.
If the baffles are installed after the integration, Webb's sunshield will be a blockade to the ISIM electronic compartments, which could make reinstalling the baffles more difficult.
Premier Observatory Of The Next Decade
The James Webb Space Telescope is the scientific successor to the Hubble Space Telescope. Scientists hope that the observatory will shed more light on the history of the universe and the evolution of the solar system.
The Webb, touted as the premier observatory of the next decade, is a collaboration of NASA, the European Space Agency, and the Canadian Space Agency.
May 2020 Launch
The telescope is set for launch in May 2020 on an Ariane 5 rocket from French Guiana. Amid mechanical problems, NASA said that it is 70 percent confident it will meet the launch date.
