After our Christmas dinner in 2021, my family and I watched the dramatic launch of NASA’s James Webb Space Telescope. This $10 billion telescope is a huge leap in technology, following the iconic Hubble. The launch was tense, as Webb had to pass through 344 possible failure points. Thankfully, it went even better than expected, and we all sighed in relief.
Fast forward six months, and the first stunning images of distant galaxies came to light. But the team back in Australia had their work cut out for them. We were tasked with using Webb’s advanced high-resolution mode known as the aperture masking interferometer (AMI). This tiny piece of metal goes into the telescope’s camera, helping to sharpen its focus.
Our research has now been published in a couple of papers on arXiv. We shared the telescope’s first successful observations of stars, planets, and even black hole jets.
Working with Webb is unique because it’s a million miles away—so we can’t send astronauts if something goes wrong. Hubble, for comparison, is close enough that it was serviced by astronauts multiple times over its lifetime. Early on, Hubble had issues because its mirror was ground incorrectly. Astronauts had to visit it to correct the problem.
One challenge with Webb is that even the tiniest distortions in its mirrors can blur images. Peter Tuthill, an Australian astronomer, designed AMI to help fix these blurs. It uses a simple pattern of holes to filter light and detect any misalignments in the telescope’s optics.
At one point, we noticed that some images were slightly blurry because of an electronic effect—brighter pixels were leaking into darker ones. This problem was significant enough that it affected Webb’s ability to distinguish distant planets that are thousands of times fainter than their parent stars.
To fix this, we collaborated with University of Sydney PhD student Louis Desdoigts to develop a computer model. This model helped us simultaneously address the distortions in both optics and electronics. After training our model on some test stars, we successfully calculated how to remove the blur from the data.
The results were astonishing. We managed to clarify images of a star hosting a faint planet and the reddest known brown dwarf—objects that were previously out of reach for Webb.
The new corrections also allowed us to capture much higher-quality images of complex targets, like Jupiter’s moon Io with its active volcanoes. We also saw jets from a black hole that were so sharp, they resembled images from much larger telescopes.
Our efforts with AMI provide a blueprint for future advancements. This technology not only enhances Webb’s current capabilities but also paves the way for upcoming missions, such as the Roman Space Telescope. If we can master the art of optical calibration, we may one day discover Earth-like planets lurking far beyond our solar system.
For more information on this research, check out The Conversation’s original article and learn about the groundbreaking work being done with the Webb Telescope.
