ICESat-2 By the Numbers: 90

The video tutorial explains how the Atlas satellite measures the slope across its laser path using three pairs of beams spaced 90 meters apart. A reference track is established between the beams. On subsequent passes, even if the beams are slightly upslope or downslope, scientists can calculate the elevation change of the key track.

How does Atlas measure the slope across the laser's path?

• Using a single pair of beams

• Using five pairs of beams

• Using three pairs of beams

• Using a single beam

What is the distance between the beams used by Atlas?

• 110 meters

• 50 meters

• 70 meters

• 90 meters

What allows scientists to calculate elevation changes even if the beams are slightly upslope or downslope?

• The change in laser frequency

• The use of multiple satellites

• The reference track between the beams

• The use of a single beam

What happens to the beams on subsequent passes?

• They are always downslope

• They remain in the exact same position

• They are always upslope

• They may be slightly upslope or downslope

Why is it important to have a reference track between the beams?

• To reduce the number of beams needed

• To ensure the beams are always parallel

• To increase the speed of the satellite

• To help calculate elevation changes