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.