NASA says it’s reviewing its options for repair and corrective action for the multibillion-dollar James Webb Space Telescope after tests shook fastening hardware off the observatory’s sunshield covers.

The issue isn’t expected to force further delays in the Webb Space Telescope’s launch, which was recently postponed to no earlier than May 2020.

Word of the loose hardware surfaced this week when Webb program director Greg Robinson referred to the issue during a presentation to the National Academies’ Space Studies Board, sparking a report in Space News. Robinson was quoted as saying “it’s not terrible news, but it’s not good news, either.”

In today’s follow-up report, NASA said it’s not uncommon for such issues to turn up during pre-launch testing. “This is an example of why space systems are thoroughly and rigorously tested on the ground to uncover imperfections and fix them prior to launch,” Robinson said in the NASA update.

He said “NASA is reviewing options for repair and the next steps in spacecraft element launch environmental testing.”

“The team is reviewing the test data and hardware configuration and is actively working towards corrective action in the near future,” Robinson said. “We expect to get back to the environmental test flow shortly and continue to move safely and methodically toward mission success.”

The telescope’s components are currently at Northrop Grumman Aerospace Systems’ facilities in Redondo Beach, Calif., for tests aimed at simulating the stresses that will be experienced during launch and deployment. The spacecraft element of the telescope — which includes the folded-up sunshield and support platform (also known as the spacecraft bus), but not the optics or scientific instruments — recently underwent two environmental tests.

One test simulated the mechanical shock caused by separation of the telescope’s payload adapter after launch. Another test subjected the spacecraft element to the extreme sound and resulting vibration that are associated with the launch. After the acoustic test, inspectors found that the fasteners designed to hold the sunshield in place during launch had come loose.

Once NASA decides exactly how to proceed, the spacecraft element is due to undergo further testing, including a simulation of the intense shaking it’ll get when it’s launched from French Guiana on an Ariane 5 rocket.

This week’s report could fuel further questions about the Webb telescope’s progress. In March, NASA announced that it was postponing the launch by an additional year, increasing its oversight of Northrop Grumman’s work and launching an independent review of the project. The agency might have to seek still more money from Congress for spacecraft development.