the James Webb Space Telescope He took his first pictures, including a “selfie”.
The mosaic image containing more than 2 billion pixels helped the Webb team determine that Webb’s Near Infrared Camera (NIRCam) tool can collect light from spiral stars.
The goal was to identify starlight from the same star in each of the telescope’s 18 primary mirror parts.
The result showed 18 randomly organized points of starlight, the product of misaligned Webb mirror segments, all reflecting light from the same star back in the secondary Webb mirror and in NIRCam detectors.
Webb’s team selected a bright, isolated star called HD 84406 and reset Webb to 156 locations around the star’s predicted position, creating 1,560 images using NIRCam’s 10 detectors over a roughly 25-hour period. This represents 54 gigabytes of raw data.
The initial search covered an area roughly the size of a full moon and light was found from all eighteen segments very close to the center.
“This initial research covered an area about the size of a full moon because the cross-section points are likely those spread across the sky,” Marshall Perrin, Webb’s deputy telescope scientist and astronomer at the Space Telescope Science Institute, said. He said in a statement. “Taking a lot of data directly on day one requires that all of Webb’s science operations and data processing systems here on Earth work seamlessly with the observatory in space from the start. And we found light from all 18 very close to the center early in this research! That’s a starting point! Great for mirror alignment.
NASA determined which point corresponds to any mirror clip, including those captured by clips on the wings of the Webb mirror.
“Right now, because Webb is still in focus, you can think of Webb as an 18-eyed creature looking in 18 separate directions. A larger dot indicates that the part is less focused than a smaller one.” The NASA Webb team explained on Twitter that the dot indicates that the part is less focused than the smaller one. The section may be tilted.
Over the next month or so, the team will gradually tweak the mirror clips until they become a single star.
The portrait was created using a custom pupil imaging lens inside the NIRCam it was designed for Rake images of basic mirror segments instead of images of space. NASA said in a blog post that the image gave an early indication of the instrument’s primary mirror alignment.
NIRCam will be used in almost all long months alignment from the telescope’s mirrors, but the agency noted that the instrument operates at a “much higher than ideal temperature” and visible artifacts can be seen in the mosaic.
The impact of these artifacts will be significantly reduced as Webb approaches optimal cryogenic operating temperatures, she said.
Going forward, Webb’s images are expected to become clearer, with more detail as the other three telescope instruments reach their intended cryogenic operating temperatures and begin capturing data.
The first scientific images are expected to appear during the summer.
“Webb’s launch into space was an exciting event, of course, but for scientists and optics engineers, this is a defining moment, when light from a star successfully makes its way through the system all the way to a detector,” Michael McElwain, Web Observatory project scientist, said.