JWST integration
The James Webb Space Telescope was installed on top of its Ariane 5 rocket Dec. 11 before the latest problem that postponed the launch. Credit: ESA/M.Pedoussaut

PARIS — A communications problem has delayed the launch of NASA’s James Webb Space Telescope by at least two more days, the agency announced late Dec. 14.

In a brief statement, NASA said that a “communication issue between the observatory and the launch vehicle system” has postponed the launch. The launch, previously scheduled for Dec. 22, is now delayed to no earlier than Dec. 24.

NASA provided no additional information about the problem, saying it would update launch plans no later than Dec. 17. Thomas Zurbuchen, NASA associate administrator for science, told Spaceflight Now that the problem is with a cable 100 meters long, part of ground support equipment, that is suffering intermittent losses of data.

This is the second incident since the arrival of JWST in French Guiana in October to delay the launch. In November, a clamp band that secures the spacecraft to its payload adapter unexpectedly released, imparting vibrations into the spacecraft. Work to test the spacecraft and confirm there was no damage to it pushed back the launch from Dec. 18 to Dec. 22. As with this latest incident, NASA provided few specifics about that issue.

As recently as Dec. 13, Arianespace and European Space Agency officials said the launch remained on schedule for Dec. 22. “The campaign is an outstanding campaign because it is lasting three months as opposed to a normal campaign, which is one month,” said Stéphane Israël, chief executive of Arianespace, during a panel discussion at Euroconsult’s World Satellite Business Week here that day. “This is the mission of the decade and we have been working on it for 20 years. We are focused.”

He added that more than 150 people from NASA are in Kourou to support the launch. “We have given to NASA to maximum visibility into our launcher.”

“I’m really very happy that NASA has entrusted this launch of a generation to ESA,” Josef Aschbacher, director general of ESA, said at the conference earlier in the day. “We’re doing our utmost and our best to be a very strong and good partner to make sure this jewel, a unique telescope that will operate for decades, will be brought safely to space.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...