Startling Star V838 Mon
Explanation:
Variable star
V838
Monocerotis startled astronomers in January of 2002,
undergoing
a dramatic outburst
like no other variable star known.
Followed closely by
ground-based instruments and the
Hubble Space Telescope
over the following months, it was soon realized that
the quickly evolving dusty nebula surrounding
V838 Mon was in fact made
visible by "light echoes" from
the outburst.
Remarkably, as light from the outburst
plays across
layers of pre-existing circumstellar material, it gives the surrounding
nebulosity the illusion
of expanding "faster than light".
Though the nebula's visible appearence changes dramatically over
a period of months, it is actually at least 6 light years
in diameter.
A good
astrophysical
explanation for V838 Mon's outbursting behavior
is still unknown but astronomers continue to follow the mystery star.
This gorgeous image, based on data recorded on October 21 with
the US Naval Observatory's
1.55 meter telescope,
adopts the color scheme used in
previous Hubble images
for easy comparison.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
