2009 Annual Report - NASA Airborne Science Program

Figure 34:
SIMPL’s shared optical bench (grey) and off-axis parabola
telescope (blue) maintains alignment between the transmit beams
and the receiver.
The ice cover results, providing an analog for sea
ice, demonstrated the unique capabilities achieved by
SIMPL. Depolarization data at both near-infrared
and visible wavelengths differentiated open water
leads, young translucent ice, older more granular
ice and snow-covered ice, important differentiators
for measuring sea ice free-board (height above
water), which is an indicator of ice thickness. The
high-precision single photon ranging differentiated
smooth ice, roughened ice and compression
ridges related to sea ice formation processes. The
SIMPL demonstration of these capabilities is
particularly important to the ICESat-2 mission
now in formulation. ICESat-2, scheduled for a
2015 launch, will use multi-beam, micropulse single
photon ranging, either at visible or near-infrared
wavelengths. ICESat-2, follow-on to the ICESat
mission, has a focus on monitoring changes in ice
sheet elevation and sea ice freeboard. SIMPL is
serving as a pathfinder for ICESat-2 technology
development.
Figure 35:
SIMPL’s receiver side.
Figure 36:
SIMPL’s transmitter side.
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