This is the first star images delivered to Earth by the new James Webb Space Telescope. It looks like 18 stars but it's actually just one captured multiple times as part of the telescope's mirror alignment process that will take three months to complete. Video explainer below.
"Launching Webb to space was of course an exciting event, but for scientists and optical engineers, this is a pinnacle moment, when light from a star is successfully making its way through the system down onto a detector," says Michael McElwain, Webb observatory project scientist, NASA's Goddard Space Flight Center, in a NASA blog post.
What you see above represents great progress for this incredible instrument that will shed light on what happened in our Universe billions of years ago. As NASA explains, the space observatory "will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System." From NASA's James Webb Telescope site:
We are pointing the telescope at a bright, isolated star (HD 84406) to capture a series of images that are then stitched together to form a picture of that part of the sky. We don't have just one mirror looking at this star; we have 18 mirrors, each of which is initially tilted towards a different part of the sky. As a result, we'll actually capture 18 slightly shifted copies of the star – each one out of focus and uniquely distorted. We refer to these initial star-copies as 'segment images.'
One by one, we will move the 18 mirror segments to determine which segment creates which segment image. After matching the mirror segments to their respective images, we can tilt the mirrors to bring all the images near a common point for further analysis. We call this arrangement an 'image array.'
