A stopwatch that can measure billionth of a second!

#NASA #space #Topology #Earth #surface #height #physics #science #ICESat-2

I am so fascinated by NASA. Always having something new to show.

We will be able to record the precise height of sea ice, glaciers, forests and other Earth’s surface with the help of a stopwatch timer that NASA scientists developed. The timer can supposedly measure within a fraction of a billionth of a second.

The engineers at NASA built the timer for ICESat-2 (Ice, Cloud and Land Elevation Satellite-2) that is scheduled to launch in 2018. The satellite will use six green laser beams to measure the height.

The laser light will be pulsed to the ground and the time for each photon to return will be recorded. This when combined with the speed of light can tell us the flight distance, combined with the knowledge of exactly where the satellite is in space, the height of Earth’s surface can be measured.

If a stopwatch is highly accurate to a millionth of a second, ICESat-2 could only measure elevation to within 500 feet. But since the clock can calculate to the billionth of a second, the satellite can measure to within 2 inches.

Read the full article here.