The new James Webb Space Telescope is topped off and one step closer to taking flight.
Mission team members have finished fueling the James Webb Space Telescope at[sic] ahead of its planned Dec. 22 launch from the Guiana Space Center in Kourou, French Guiana, the European Space Agency announced Monday (Dec. 6). The fueling for Webb, which is an international collaborative effort between NASA, ESA and the Canadian Space Agency, took 10 days and was completed on Dec. 3, according to the ESA statement.
After a series of delays since the development of the scope first began in 1996, Webb is still on track to finally launch Dec. 22 atop an Arianespace Ariane 5 rocket from the Guiana Space Center in Kourou, French Guiana.
"Webb's propellant tanks were filled separately with [21 gallons] 79.5 l of dinitrogen tetroxide oxidizer and [42 gallons] 159 l hydrazine," the ESA wrote in the announcement, adding that the oxidizer "improves the burn efficiency of the hydrazine fuel."
Now that Webb is fueled, the mission team will begin "combined operations," according to the statement. In this phase, the teams behind the rocket and the telescope will come together to mount Webb on the Ariane 5 rocket and encapsulate it within the rocket's fairing. The newly joined pair will then be moved to the Final Assembly building for final preparations before liftoff.
In preparation for launch later this month, ground teams have successfully completed the delicate operation of loading the James Webb Space Telescope with the propellant it will use to steer itself while in space.
In order to make critical course corrections shortly after launch, to maintain its prescribed orbit nearly 1 million miles from Earth, and to repoint the observatory and manage its momentum during operations, Webb was built with a total of 12 rocket thrusters. These rocket thrusters use either hydrazine fuel or a special mixture of hydrazine fuel and dinitrogen tetroxide oxidizer.
To safely handle these extremely toxic propellants, Webb was moved to the fueling section of the Ariane payload preparation facility at Europe's Spaceport in French Guiana. Specialists wore Self-Contained Atmospheric Protective Ensemble, or "SCAPE," suits while loading the observatory. The nearly 10-day procedure began Nov. 25.
[...] The next large milestones for the joint teams will be to move Webb to the Bâtiment d'Assemblage Final (BAF), or Final Assembly Building; place it atop its rocket; and encapsulate it inside its protective fairing. With final closeouts complete, the full stack of rocket and payload atop its mobile launch platform will be rolled out of the BAF to the launch pad, two days before its scheduled Dec. 22 launch.
The James Webb Space Telescope is due to launch on Saturday (Dec. 25) during a 32-minute window that opens at 7:20 a.m. EST (1220 GMT). The massive observatory will blast off from Kourou, French Guiana, atop an Ariane 5 rocket operated by European launch provider Arianespace. You can watch launch coverage live at Space.com beginning at 6 a.m. EST (1100 GMT) courtesy of NASA or you can watch directly at the agency's website.
ESA launch kit (PDF).
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