US space agency NASA continues to surprise and inspire the next generation of astronomers, scientists, physicists and all other breeds of researchers to continue striving for newer heights through a range of inventions and discoveries and latest such invention joining the list is a stopwatch that can measure billionth of a second.

The space agency hasn’t limited it vision to space and continues to carry out research in a number of topics including climate change, global warming, sea ice levels, physics and a number of other such topics.

NASA’s latest work involves a stopwatch timer that can measure time within a billionth of a second! This will help scientists to record precise height of sea, ice, glaciers, forests and any other surface on Earth. With such incredibly precise measurements, scientists can actually calculate the distance between a satellite and the Earth. Based on these records, they can also measure height and depth of surfaces on Earth.

If this stopwatch kept time even to a highly accurate millionth of a second, ICESat-2 could only measure elevation within 500 feet which roughly amounts to the top of a five-story building from the ground. And when it comes to measuring light, Tom Neumann- ICESat-2’s deputy project scientist said that light moves real quick and if one even desires to measure it amounting to the accuracy to a couple of centimetres, they need a very good clock.

To reach the needed precision to a fraction of a billionth of a second, engineers had to develop and design their own series of clocks on satellite’s instruments – the Advanced Topographic Laser Altimeter System (ATLAS). ATLAS pulses beams of laser light to the ground and later records the time it takes for the photon to return. The recorded time coupled with the speed of light tells researchers the distance the laser has travelled. This flight distance combined with the knowledge of the exact position of the satellite in space, further describes the height of the Earth’s surface below.

There is a GPS receiver which ticks off every second – a coarse clock that tells time for the satellite. This timing clock itself consists of several parts to keep better track of time. The timing accuracy that it responds to allows researchers to measure heights within the range of about two inches.