ICESat-2 Por Los Números: 300 Trillones

The Atlas instrument's laser emits photons that scatter in all directions after bouncing off the Earth. Only a few photons are reflected directly back to the instrument. Despite the small number, Atlas accurately measures the time it takes for these photons to return, enabling precise calculations of surface elevation.

Why is it important for Atlas to measure the time it takes for photons to return?

What can scientists calculate using the data measured by Atlas?