                        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.

                                2020 July 21

                        Iron in the Butterfly Nebula
     Image Credit: NASA, ESA, Hubble; Processing & License: Judy Schmidt

   Explanation: Can stars, like caterpillars, transform themselves into
   butterflies? No, but in the case of the Butterfly Nebula -- it sure
   looks like it. Though its wingspan covers over 3 light-years and its
   estimated surface temperature exceeds 200,000 degrees, C, the dying
   central star of NGC 6302, the featured planetary nebula, has become
   exceptionally hot, shining brightly in visible and ultraviolet light
   but hidden from direct view by a dense torus of dust. This sharp
   close-up was recorded by the Hubble Space Telescope and is reprocessed
   here to show off the remarkable details of the complex planetary
   nebula, highlighting in particular light emitted by iron, shown in red.
   NGC 6302 lies about 4,000 light-years away in the arachnologically
   correct constellation of the Scorpion (Scorpius). Planetary nebulas
   evolve from outer atmospheres of stars like our Sun, but usually fade
   in about 20,000 years.

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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Phillip Newman Specific rights apply.
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