A-Train Satellites and Shizuku's Observations

A train of satellites is orbiting Earth right now, flying in a perfect line.

It’s called the A-Train, and one of its members is a Japanese satellite named "Shizuku,"

which means "water drop." From 700 kilometers up, its spinning sensor

uses microwaves to see things our eyes can't. It measures the temperature of the

ocean, the amount of water in clouds, the moisture in the soil,

and even the depth of snow. As it flies, it scans a massive 1,600-kilometer-wide

path on the surface. And because Earth isn't a perfect ball, the data is constantly

corrected for the height of mountains.