Acceptance testing

Raytheon completed factory acceptance testing of the flight operations system for the James Webb Space Telescope (JWST). With seven times the light-collecting power of its predecessor, the Hubble Space Telescope, this next-generation telescope will gather data and images of dust clouds, stars and galaxies deeper into space.

The James Webb Space Telescope (sometimes called JWST or Webb) will be a large infrared telescope with a 6.5-meter primary mirror
The James Webb Space Telescope (sometimes called JWST or Webb) will be a large infrared telescope with a 6.5-meter primary mirror

Over 800 requirements were successfully verified on the JWST ground control system during the testing conducted at Raytheon’s Aurora, Colorado, facility, bringing NASA’s next space observatory one step closer to the scheduled 2018 launch.

«The JWST flight operations system is our latest generation of mission management and command and control capabilities for satellite operations», said Matt Gilligan, vice president of Raytheon Navigation and Environmental Solutions. «Our ground control system will download data from space and fly the telescope as it penetrates through cosmic dust to unlock the universe’s secrets like never before».

JWST takes observations in the infrared spectrum to penetrate cosmic dust to reveal the universe’s first galaxies, while observing newly forming planetary systems. JWST is expected to make observations for five years, will carry enough fuel for 10 years, and is designed to withstand impacts of space debris as it orbits far beyond the Earth’s Moon.

Raytheon installed the ground control system for JWST on the campus of the Johns Hopkins University in Baltimore, Maryland, under contract to the Space Telescope Science Institute.


Vital Facts

Proposed Launch Date JWST will be launched in October 2018
Launch Vehicle Ariane 5 ECA
Mission Duration 5 – 10 years
Total payload mass Approximately 6,200 kg/13,669 lbs, including observatory, on-orbit consumables and launch vehicle adaptor
Diameter of primary Mirror ~6.5 m/21.3 feet
Clear aperture of primary Mirror 25 m2/269 square feet
Primary mirror material beryllium coated with gold
Mass of primary mirror 705 kg/1,554 lbs
Mass of a single primary mirror segment 20.1 kg/44.3 lbs for a single beryllium mirror, 39.48 kg/87 lbs for one entire Primary Mirror Segment Assembly (PMSA)
Focal length 131.4 m/431.1 feet
Number of primary mirror segments 18
Optical resolution ~0.1 arc-seconds
Wavelength coverage 0.6 – 28.5 microns
Size of sun shield 21.197 × 14.162 m/69.5 × 46.5 feet
Orbit 1.5 million km from Earth orbiting the second Lagrange point
Operating Temperature under 50 K/-370 °F
Gold coating Thickness of gold coating = 100 × 10-9 meters (1000 angstroms). Surface area = 25 m2. Using these numbers plus the density of gold at room temperature (19.3 g/cm3), the coating is calculated to use 48.25 g of gold, about equal to a golf ball (A golf ball has a mass of 45.9 grams)


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