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Webb Telescope in full focus, ready for instrument commissioning

Webb - Telescope alignment evaluation image

While the purpose of this image was to focus on the bright star at the center for alignment evaluation, Webb's optics and NIRCam are so sensitive that the galaxies and stars seen in the background show up. At this stage of Webb's mirror alignment, known as "fine phasing," each of the primary mirror segments have been adjusted to produce one unified image of the same star using only the NIRCam instrument. This image of the star, which is called 2MASS J17554042+6551277, uses a red filter to optimize visual contrast. (Credit: NASA/STScI)

On , assisted by the Canadian Space Agency's Fine Guidance Sensor, the Webb team completed the stage of mirror alignment known as "fine phasing." At this key stage in the commissioning of Webb's Optical Telescope Element, every optical parameter that has been checked and tested is performing at, or above, expectations. The observatory is able to successfully gather light from distant objects and deliver it to its instruments without issue.

Although there are months to go before Webb ultimately delivers its new view of the cosmos, achieving this milestone means the team is confident that Webb's first-of-its-kind optical system is working as well as possible.

With the fine phasing stage of telescope alignment completed, the team has now fully aligned Webb's primary imager, the Near-Infrared Camera, with the observatory's mirrors.

Over the next six weeks, the team will proceed through the next of several remaining alignment steps before final science instrument preparations. The team will further align the telescope to include the Near-Infrared Spectrograph, the Mid-Infrared Instrument, and the Canadian-built Near Infrared Imager and Slitless Spectrograph. In this phase of the process, an algorithm will evaluate the performance of each instrument and then calculate the final corrections needed to achieve a well-aligned telescope across all science instruments. Following this, Webb's final alignment step will begin, and the team will adjust any small, residual positioning errors in the mirror segments.

By late or early , the team is on track to conclude all aspects of Optical Telescope Element alignment and move on to approximately two months of science instrument preparations. Webb's first full-resolution imagery and science data will be released in early to mid-.

Webb is an international program led by NASA with its partners, the European Space Agency and the Canadian Space Agency. Webb's science operations are overseen for NASA by the Space Telescope Science Institute in Baltimore.

Abridged text is reprinted courtesy of NASA

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