Astronomy's future waits on NASA's next big telescope

The high-profile, high-price tag James Webb Space Telescope is finally moving closer to launch.

Why it matters: The Webb has been in development by NASA for far longer than expected, and while other missions have moved ahead in that time, getting the powerful telescope to space is a top priority.

• The Nancy Grace Roman telescope is on deck after the Webb, and NASA is expected to select a new flagship mission in the coming months that will require a wealth of resources as well.
• The Roman telescope, expected to gather data to help scientists understand dark matter and dark energy, will have a view 100 times larger than the Hubble.

Driving the news: The Webb is now in the final stages of testing in the U.S. before being shipped to French Guiana ahead of its expected launch from there at the end of October.

• Scientists have already doled out the first year of observation time for the telescope.
• "We're going to be able to piece together what the universe's story was in the first billion years after the Big Bang," says Caitlin Casey, an astronomer at the University of Texas at Austin, who co-leads a team that received a large allocation of time with the Webb.

Yes, but: A problem with the Ariane 5, the rocket expected to take the Webb to space, could still delay the mission, according to a SpaceNews report.

• Last week, the U.S. Government Accountability Office released a report detailing 39 risks that still threaten the success of the telescope before and after launch.
• Most of those technical risks — including the telescope's deployment once in space — will need to be managed after launch. The report doesn't offer new recommendations to NASA on how to manage them, saying the space agency instituted fixes for management issues in 2019.

Background: The Webb could transform space science, revealing the light of never-before-seen galaxies and stars. But there have been billions of dollars in budget overruns and delays for the telescope.

• "It's the most complex piece of civil space robotics in all of human history," astronomer Grant Tremblay told me.

The Webb's development has been long and filled with setbacks, but that isn't unprecedented.

• The Hubble Space Telescope’s early years in space were marked by a major problem with a mirror, which eventually forced NASA to launch a crew of astronauts to service it.
• The Webb, however, won't have that option if all doesn't go to plan after launch. The telescope will be about 1 million miles from Earth, too far away for a crewed mission to reach it.

The big picture: Researchers working on telescopes expected to follow Webb in the pipeline have also learned from the errors made during its development.

• Scientists are currently proposing large flagship missions to follow along after the Roman telescope launches, and those potential missions have better budget models, more realistic timelines and development plans than the Webb did at this stage.
• "Everything's just so much more advanced thanks in part to lessons learned from Webb," Tremblay added.