Northrop Grumman delivered to NASA the flight software that will enable the James Webb Space Telescope to communicate with its ground station nearly a million miles away after it passed formal verification testing. The company is leading the telescope's design and development effort for NASA's Goddard Space Flight Center in Greenbelt, Md.

Northrop Grumman engineers verified that the flight software met the Webb mission requirements for ground commands to the spacecraft and science data delivery to the ground station.

Formal verification testing of flight software for launch and deployment is slated for completion by summer 2012, followed by software for attitude and thermal control.

The spacecraft program has also completed critical design reviews that represent substantial progress for the bus design. These include three subassemblies:

+ The primary structure that supports the observatory during launch and operations. This 350 kilogram graphite composite structure is designed to support 6.5 metric tons.

+ The propulsion structure module, which supports the spacecraft propulsion subsystem responsible for orbit insertion and maintenance.

+ The cone assembly, which mates the primary observatory support structure to the Ariane 5 launch vehicle.

"Early completion of flight software verification testing achieved cost savings and significant risk retirement for the program," said Andrew Cohen, Webb spacecraft manager, Northrop Grumman Aerospace Systems.

"With the addition of three spacecraft critical design reviews completed, as well as advancements on our propulsion systems, we are making important progress."

In addition, technical progress continues on several other major components.

A critical design review confirmed a thermal upgrade to 16 monopropellant rocket engine (MRE-1) thrusters which were modified to withstand the high temperatures on the spacecraft generated by both the sun and reflected heat from the sunshield.

The 6-inch long MRE-1 thrusters provide one pound of thrust each to unload momentum and provide precision attitude control on orbit.

Propulsion engineers have also completed building four flight Secondary Combustion Augmented Thrusters, which provide eight pounds of thrust each and supply orbit maintenance after the launch vehicle finishes its burns.

Three more spacecraft subassembly critical design reviews are scheduled for next year: in January a spacecraft-to-telescope vibration isolator; in April a sunshield support structure subassembly; and in June, the support structure for the communications downlink antenna to the Deep Space Network.

Successor to the Hubble Space Telescope, the James Webb Space Telescope is the world's next-generation space observatory. It is the most powerful space telescope ever built.

Webb will observe the most distant objects in the universe, provide images of the very first galaxies ever formed and study planets around distant stars. The Webb Telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency.