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.

What happens to the photons emitted by the Atlas instrument's laser when they hit the Earth's atmosphere?

• They increase in number.

• They disappear completely.

• They scatter in all directions.

• They are absorbed by the atmosphere.

How many photons does the Atlas instrument typically receive back?

• None

• Thousands

• About a dozen

• Hundreds

Why is the number of photons received by Atlas considered minuscule?

• Because they are not emitted at all.

• Because they scatter in all directions.

• Because they are too large to measure.

• Because they are absorbed by the Earth.

What does Atlas measure to help scientists calculate surface elevation?

• The size of the photons

• The time it takes for photons to return

• The speed of the photons

• The color of the photons

How does the accurate measurement of photon return time benefit scientists?

• It helps in predicting weather patterns.

• It changes the color of the photons.

• It increases the number of photons received.

• It allows for precise calculation of surface elevation.