The Spectrum of a Meteor
Chasing the brief
flash of a meteor trail across
the sky with a very large telescope is a nearly impossible task.
But on May 12, 2002,
astronomers got lucky,
as a bright meteor chanced across the narrow slit of their
spectrograph at the
Paranal Observatory.
At the time, the spectrograph was being used to
study the light from
a supernova, separating and recording the many
near-infrared emission lines produced by atoms
in the distant stellar explosion.
Below this artistic montage of a meteor streak and
Very Large Telescope units at Paranal,
panel a shows the near-infrared sky background spectrum and the
May 12 meteor combined.
Panel b shows the emission spectrum of the meteor alone, after
subtracting away the background contributions.
The meteor emission is due to colliding oxygen and nitrogen atoms
and molecules in the superheated air along
the glowing trail
at an altitude of about 100 kilometers.