Explanation:
Beginning with a full view of beautiful spiral
galaxy M81,
follow the insets (left, bottom, then right) to
zoom in
on a real survivor.
Seen at the center of the final field on the right is a star
identified as the survivor of a cosmic cataclysm --
the supernova explosion of its companion star.
Light from the cosmic blast, likely triggered by the
core collapse of a star initially more than 10 times as massive as the Sun,
first reached Earth over 10 years ago and was
cataloged as
supernova SN 1993J.
Though the supernova itself is no longer visible,
light-echoes from
dust in the region can still be seen near the companion, the first
known survivor of a
supernova
in a binary star system.
Astronomers believe that a substantial
transfer of material
to the surviving companion star during the last few hundred years
before the stellar explosion can explain peculiarities seen
in this
supernova.
After supernova SN 1987A in the
Large Magellanic Cloud, SN 1993J
in nearby M81 is the brightest supernova seen in modern times.
