                        Astronomy Picture of the Day

    Discover the cosmos! Each day a different image or photograph of our
      fascinating universe is featured, along with a brief explanation
                    written by a professional astronomer.

                                2022 March 19

                           2MASS J17554042+6551277
                      Image Credit : NASA, STScI, JWST

   Explanation: 2MASS J17554042+6551277 doesn't exactly roll off the
   tongue but that's the name, a coordinate-based catalog designation, of
   the star centered in this sharp field of view. Fans of the distant
   universe should get used to its spiky appearance though. The
   diffraction pattern is created by the 18 hexagonal mirror segments of
   the James Webb Space Telescope. After unfolding, the segments have now
   been adjusted to achieve a diffraction limited alignment at infrared
   wavelengths while operating in concert as a single 6.5 meter diameter
   primary mirror. The resulting image taken by Webb's NIRcam demonstrates
   their precise alignment is the best physics will allow. 2MASS
   J17554042+6551277 is about 2,000 light-years away and well within our
   own galaxy. But the galaxies scattered across the background of the
   Webb telescope alignment evaluation image are likely billions of
   light-years distant, far beyond the Milky Way.

                       Tomorrow's picture: day = night
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Phillip Newman Specific rights apply.
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                             & Michigan Tech. U.

