Nebula with Laser Beams
Explanation:
Four
laser beams cut across this startling image of the
Orion Nebula, as seen from ESO's Paranal Observatory in
the Atacama desert on
planet Earth.
Not part of an
interstellar conflict,
the lasers are being used for an observation of Orion
by UT4,
one of the observatory's very large telescopes,
in a technical test of an
image-sharpening
adaptive optics system.
This view of the nebula with laser beams was
captured by a small telescope from outside the UT4 enclosure.
The beams are visible from that perspective because in the
first few kilometers above the observatory the Earth's dense
lower atmosphere scatters the laser light.
The four small segments appearing beyond the beams are emission
from an atmospheric layer of sodium atoms excited by the laser light
at higher altitudes of 80-90 kilometers.
Seen from the perspective of the UT4, those segments form bright
spots or artificial guide stars.
Their fluctuations are used in real-time to correct for
atmospheric blurring along the line-of-sight by controlling a
deformable mirror
in the telescope's optical path.
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.
