NASA's James Webb Space Telescope completely aligned and fully focused

Scientists working on NASA's James Webb Telescope have reached an important milestone, completely aligning the space observatory's massive mirrors. The achievement means the team can now move ahead with configuring the onboard instruments and prepare them to begin capturing sharp and in-focus images of the cosmos.

Back in January, the James Webb Space Telescope (JWST) finished deploying its set of 18 mirrors, which it will use to direct light from cosmic objects onto its instruments to capture images. But to do so, the mirrors had to be precisely aligned over a three-month period in order to focus that light correctly.

In March, the mirrors were brought into alignment with the telescope's primary imaging instrument, the Near-Infrared Camera, enabling it to focus and snap a crystal-clear image of a bright star. The team then continued aligning the mirrors with the JWST's remaining instruments, the Near-Infrared Spectrograph, Mid-Infrared Instrument, and Near Infrared Imager and Slitless Spectrograph – a task that is now complete.

The team confirmed the mirrors were aligned and directing light onto the JWST's four instruments by capturing a set of test images covering the telescope's full-field of view, seen below. The scientists say the optical performance of the telescope continues to exceed even their most optimistic expectations.

“These remarkable test images from a successfully aligned telescope demonstrate what people across countries and continents can achieve when there is a bold scientific vision to explore the universe,” said Lee Feinberg, Webb optical telescope element manager at NASA’s Goddard Space Flight Center.

With the mirrors now in position (save for some slight periodic adjustments here and there), the scientists are now turning their attention to commissioning of the science instruments. The unique lenses, masks, filters and other gear that make these highly sophisticated instruments tick will need to be precisely configured over the next two months, to ready the telescope for the start of its science operations in the middle of the year.

“With the completion of telescope alignment and half a lifetime’s worth of effort, my role on the James Webb Space Telescope mission has come to an end,” said Scott Acton, Webb wavefront sensing and controls scientist, Ball Aerospace. “These images have profoundly changed the way I see the universe. We are surrounded by a symphony of creation; there are galaxies everywhere! It is my hope that everyone in the world can see them.”

The video below provides an overview of the achievement.

Source: NASA