Explanation:
The star system GK Per is known to be associated
with only two of the three nebulas
pictured.
At 1500
light years distant,
Nova Persei 1901
(GK Persei)
was the second closest
nova yet recorded.
At the very center is a
white dwarf star, the surviving core of a former Sun-like star.
It is surrounded by the circular
Firework nebula, gas that was ejected by a
thermonuclear explosion
on the white dwarf’s surface — a nova — as
recorded in 1901.
The red glowing gas surrounding the Firework nebula
is the atmosphere that used to surround the central star.
This gas was expelled before the
nova and appears as a diffuse
planetary nebula.
The faint gray gas running across is
interstellar cirrus that seems to be
just passing through
coincidently.
In 1901, GK Per’s nova
became brighter than
Betelgeuse.
Similarly, star system
T CrB is expected to
erupt in a nova later this year,
but we don’t know exactly when nor
how bright it will become.