SOFIE is being built by the
Space Dynamics Laboratory
The SOFIE PI is Larry
Gordley
of GATS Inc.
Mark Hervig (SOFIE Deputy PI) m.e.hervig@gats-inc.com
SOFIE is one of three instruments onboard the Aeronomy of Ice in the Mesosphere (AIM) satellite. The objective of AIM is to study polar mesospheric clouds (PMCs) and the environment in which they form.
SOFIE uses the technique of solar
occultation to measure solar energy passing
through the limb of the earth's atmosphere as the sun rises or sets
relative to the spacecraft. These
measurements are accomplished using
differential absorption radiometry with eight band
pairs covering wavelengths from 0.29 to 5.26 microns.
Six SOFIE channels are
designed to measure gaseous signals, and two are
dedicated to PMC measurements. Measurements
in two carbon dioxide bands will be used to simultaneously retrieve
profiles of temperature
and carbon dioxide mixing ratio. Each
SOFIE channel uses two
detectors, one that samples a spectral region where the
target gas is strongly absorbing, and one that samples a weakly
absorbing region. Measuring
the difference of these signals allows precise isolation of the target
gas signal and reduces common-mode noise. The measurements allow PMC
extinction retrievals using the gas channel weak bands, so that PMCs
will be measured at a total of 11 wavelengths.
The AIM spacecraft was launched on 25 May 2007.