Success for NASA's Webb Telescope as its two halves communicate

1 min read

For the first time, the two halves of NASA's James Webb Space Telescope - the spacecraft and the telescope - were connected together using temporary ground wiring that enabled them to "speak" to each other like they will in flight.

Although it was a significant step forward for the program, this test was an optional "risk reduction" test that took advantage of an opportunity to connect the two halves of the observatory together electrically months earlier than planned. If any issues had been found, it would have given engineers more time to fix them and without causing further delays. As a bonus, it also provided a jumpstart for the separate spacecraft and telescope test teams to begin working jointly as they will when the whole observatory is put together in one piece next year.

Scientists anticipate the James Webb telescope’s findings to rewrite textbooks on astronomy by providing revolutionary observations of the cosmos, while engineers and involved technicians forecast that its challenging design will enable and influence future spacecraft architecture for years to come.

"What we did now was make electrical connections between the flight telescope and flight spacecraft to understand all the nuances of the electrical interface. Specifically, in this test the spacecraft commanded mirror motion on the telescope, and the telescope replied back with telemetry confirming it,” said Mike Menzel, Webb's Mission System Engineer.

“Even though we have tested each half with a simulator of the other half during their parallel construction, there is nothing exactly like connecting the real thing to the real thing. While the sunshield was being reassembled to get back into its environmental testing, we took advantage of the time and did a flight-to-flight electrical dry run right now to reduce schedule risk later. The full complement of electrical and software tests will be run next year when the observatory is finally fully assembled for flight."

The James Webb Space Telescope will examine every phase of cosmic history: from the first luminous glows after the big bang to the formation of galaxies, stars, and planets to the evolution of our own solar system. Webb intends to broaden and enrich the discoveries achieved by the great space observatories Hubble, Spitzer, and Chandra.

"This test also afforded us an early chance to ensure that the two teams, who had been working separately over the years building and testing the two separate halves of Webb respectively, were able to operate as a single observatory test team,” added Jeff Kirk, Test Operations Lead. “We are enthused that the early communications and commanding risk reduction test has been successfully executed. The procedure was designed and executed by an integrated set of team members from Goddard Space Flight Center, Northrop Grumman, and Ball Aerospace.”