                        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.

                              2026 September 22
   An image of the Sun is shown with several dark silhouettes superposed.
    On the upper right is an airplane, on the right is the International
   Space Station, and across the Sun are several sunspots. Please see the
                 explanation for more detailed information.

             Chance Triple Alignment: Plane, Space Station, Sun
        Image Credit & Copyright: Petr Horalek / Inst. Physics Opava

   Explanation: This shot captured an unexpected silhouette. Which is it?
   It isn't the sunspots, the small dark regions caused by concentrated
   magnetic fields visible around the Sun's bright disk. Sunspots
   typically last for weeks and were expected, since these spots were seen
   previously. It isn’t the International Space Station (ISS), the small
   dark structure on the middle left.  This is because the featured
   picture was planned with sub-second timing to record the iconic
   structure passing before the Sun. It is the airplane. Just as this
   exposure was taking place in June, from Prasek in the Czech Republic,
   an airplane began its own miniature partial eclipse. The result is this
   triply aligned image of our Sun. The photographer estimates that the
   chance of any random Sun image containing silhouettes of both a space
   station and an airplane, from that location, is about 30 million to
   one.

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                       Tomorrow's picture: open space
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Amber Straughn Specific rights apply.
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                             & Michigan Tech. U.

