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2014 June 17
V838 Light Echo: The Movie
Image Credit:
ESA,
NASA,
Hubble Space Telescope;
Music: The Driving Force
(Jingle Punks)
Explanation:
What caused this outburst of V838 Mon?
For reasons unknown, star
V838 Mon
suddenly became one of the brightest stars in the entire
Milky Way Galaxy.
Then, just a few months later, it faded.
A stellar flash like this has never been seen before --
supernovas
and
novas expel a tremendous amount of matter out into space.
Although the
V838 Mon flash appeared to expel some material into space, what is seen in the
above eight-frame movie, interpolated for smoothness, is actually an outwardly moving
light echo of the flash.
The actual time-span of the
above movie
is from 2002, when the flash was first recorded, to 2006.
In a
light echo, light from the flash is
reflected by successively more distant ellipsoids in the complex array of ambient
interstellar dust
that already surrounded the star.
Currently, the
leading model for
V838's
outburst was the orbital decay and subsequent merging of two relatively normal stars.
V838 Mon lies about 20,000
light years away toward the
constellation of
Monoceros, while the largest
light echo above spans about
six light years in diameter.
Tomorrow's picture: big footprint
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Authors & editors:
Robert Nemiroff
(
MTU) &
Jerry Bonnell (
UMCP)
NASA Official: Phillip Newman
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