Skip to main content

NASA offers important update on health of James Webb Space Telescope

NASA has delivered good news on the health of the James Webb Space Telescope following a recent incident that could have caused a serious delay to its launch schedule.

The most powerful space telescope ever built suffered a scare earlier this month when a clamp band — used to secure Webb to the launch vehicle adapter — suddenly released as the spacecraft was being attached to the upper stage of the Ariane 5 rocket at the launch site in French Guiana.

The unexpected event caused a vibration to pass through the observatory that engineers feared could have damaged some of its components.

Following thorough checks, NASA reported on Wednesday that the observatory and spacecraft are in good shape, allowing it to stick with the most recently announced launch date of December 22.

“A NASA-led anomaly review board concluded no observatory components were damaged in the incident,” the space agency said in a post on its website. “A ‘consent to fuel’ review was held, and NASA gave approval to begin fueling the observatory. Fueling operations will begin Thursday, November 25, and will take about 10 days.”

The James Webb Space Telescope is the result of an international collaboration between NASA and the European and Canadian space agencies.

Once deployed, it will set about exploring deep space in the hope of learning more about our solar system and beyond.

“Webb will reveal new and unexpected discoveries, and help humanity understand the origins of the universe and our place in it,” NASA said.

The telescope is the successor to the Hubble Space Telescope, which has been exploring the universe since 1990 and beaming back some incredible imagery.

There are a number of key differences between the two observatories. As per NASA: “Webb will primarily look at the universe in the infrared, while Hubble studies it primarily at optical and ultraviolet wavelengths (though it has some infrared capability). Webb also has a much bigger mirror than Hubble. This larger light-collecting area means that Webb can peer farther back into time than Hubble is capable of doing. Hubble is in a very close orbit around the earth, while Webb will be 932,000 miles (1.5 million km) away.”

The video below offers a size comparison of Webb and Hubble’s mirrors. Also check out the enormous sunshield located below Webb’s mirror, said to be the size of a tennis court.

Primary Mirror Size Comparison Between Webb and Hubble

The Webb observatory in its open state is too large to fit into a rocket’s nose cone. The solution was to build a foldable design that will unfurl once it’s in space.

With NASA having delivered good news about the James Webb Space Telescope, we can now look forward to the launch happening in just a few weeks from now. Check back nearer the time for full details on how to watch a livestream of the lift-off.

Trevor Mogg
Contributing Editor
Not so many moons ago, Trevor moved from one tea-loving island nation that drives on the left (Britain) to another (Japan)…
James Webb Space Telescope has gone cold, but that’s good
The James Webb Space Telescope.

Almost four months after launch, the James Webb Space Telescope has just taken a big step toward making its first observations of deep space.

The $10 billion mission -- a joint effort involving NASA, the European Space Agency, and the Canadian Space Agency -- is on a quest to find out more about the origins of the universe while at the same time searching for distant planets that may support life.

Read more
One of James Webb’s first targets is Jupiter. Here’s why
Artist's conception of the James Webb Space Telescope

Astronomers the world over are buzzing with anticipation for the new science that will be possible once the James Webb Space Telescope, the world's most powerful space telescope, completes its commissioning. Since the telescope launched on December 25, 2021, it has unfurled its hardware into its final configuration, reached its final orbit around the sun, and completed aligning its mirrors with its primary camera, but there are still steps like the calibration of its instruments to go before it is ready for scientific use.

As soon as the commissioning phase is complete, which is set to wrap up this summer, the science observations will begin. And this is where things get exciting, as the telescope's high sensitivity and infrared capabilities will enable it to observe extremely distant objects, even fainter than those observed by current space-based telescopes like Hubble. It will usher in a new era of astronomical observations and could help to investigate topics as wide-ranging as how the first galaxies formed and whether planets in other star systems have atmospheres or not.

Read more
James Webb’s MIRI instrument about to face most daunting challenge yet
MIRI is inspected in the giant clean room at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, in 2012.

In the long process of getting ready to take its first scientific observations this summer, the James Webb Space Telescope now has three out of its four instruments aligned to its mirrors. The fourth instrument, MIRI or the mid-infrared instrument, will take a little longer because it uses a different type of sensor which needs to be kept at an extremely low temperature -- and achieving this temperature requires, perhaps surprisingly, both a cooler and a heater. Now, NASA has shared an update on the process of getting MIRI down to temperature and ready for operations.

Webb's three other instruments are already at their chilly operating temperatures of 34 to 39 kelvins, but MIRI needs to get all the way down to 7 kelvins. To achieve that, the instrument has a special cryocooler system. “Over the last couple of weeks, the cryocooler has been circulating cold helium gas past the MIRI optical bench, which will help cool it to about 15 kelvins," cryocooler specialists Konstantin Penanen and Bret Naylor at NASA's Jet Propulsion Laboratory wrote. "Soon, the cryocooler is about to experience the most challenging days of its mission. By operating cryogenic valves, the cryocooler will redirect the circulating helium gas and force it through a flow restriction. As the gas expands when exiting the restriction, it becomes colder, and can then bring the MIRI detectors to their cool operating temperature of below 7 kelvins."

Read more