NASA launched the ICESat-2 satellite, using laser to measure changes in the earths ice.

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 NASA launched the ICESat-2 satellite, using laser to measure changes in the earths ice.


The ICESat-2 satellite will use 6 green laser beams to scan the earths surface to measure glaciers and floating sea ice. By measuring the thickness and mass of ice accurately, NASA scientists will be able to better understand the effects of climate change, the researchers said. Were trying to understand the processes and drivers of climate change to better predict sea level rise, said Tom Wagner, a scientist at NASAs Washington-based Cryosphere Project.

In addition, when the ICESat-2 satellite orbits the Earth from one pole to the other, it can also measure the height of forests, jungles and other terrain. These data will be used to estimate how much carbon is being lost in temperate regions of the Earth and how much is being lost over time.

Engineers spent 10 years designing and building the ICESat-2 satellite, which costs about $1 billion, and will take off on a Delta-2 rocket. The most difficult problem in design is how to make the laser beams work together as a whole and ensure that they are properly aligned to obtain accurate information. In addition, we need to get the location of the satellite through the GPS device and the camera pointing to the outer space.

ICESat-2. The satellite will emit 10,000 laser pulses per second to Earth, capture the returned beams through a 31-inch wide beryllium telescope and send them to an electronic signal detector to calculate the distance to Earth. Six laser beams form a six-kilometer-wide band that measures everything in the area (the laser is harmless to humans, plants and ice).

ICESat-2, weighing 341 pounds (about 155 kg), is a long-awaited replacement for the original ICESat satellite, which ended its single-laser mission in 2009. Since then, during Operation Ice Bridge, researchers have been flying specially equipped P-3B and DC-8 aircraft in the Arctic and Antarctic to fill the pre-launch data gap for ICESat-2. The ICESat-2 satellite is equipped with ATLAS (Advanced Terrain Laser Altimeter System), which emits photons that take 3.3 milliseconds to reach Earth and return. According to NASA, the measurement error of ATLAS can be reduced to 1/1000000000 seconds. Using the laws of physics, scientists can calculate the distance from the satellite to the earths surface, accurate to 4 millimeters.

By comparing this distance with the distance measured at the same place a few days or weeks ago, you can calculate how ice melts (or swells) and how plants grow. Most importantly, the ICESat-2 satellite will measure the elevation changes in Greenland and Antarctica within a year.

NASA says researchers know that Arctic sea ice is shrinking, but little is known about its volume changes. ICESat-2 is the first satellite capable of measuring sea ice thickness. The satellites laser beam reflects from the ice surface and then compares it with the laser reflection from nearby waters to get the height of the ice around the open water.

Wagner of the National Aeronautics and Space Administration (NASA) says the improved ATLAS is a huge leap forward in collecting large amounts of data in areas beyond the reach of planets on Earth. He says the device is particularly useful in areas where we dont know how its changing, such as the depths of Antarctica and some coastal areas. Kelly Brunt, a glaciologist at NASAs Goddard Space Flight Center in Greenbelt, Maryland, says ICESat-2 will help her better understand the intersection of the permanent ice sheet and the surrounding floating ice shelves, known as the grounding zone. We also want to see new science that weve never imagined, because humans are creative and break through the limits of data, she said. (Vicky) the source of this article: NetEase science and technology report editor: Zhang Jie _NT5630

Wagner of the National Aeronautics and Space Administration (NASA) says the improved ATLAS is a huge leap forward in collecting large amounts of data in areas beyond the reach of planets on Earth. He says the device is particularly useful in areas where we dont know how its changing, such as the depths of Antarctica and some coastal areas.

Kelly Brunt, a glaciologist at NASAs Goddard Space Flight Center in Greenbelt, Maryland, says ICESat-2 will help her better understand the intersection of the permanent ice sheet and the surrounding floating ice shelves, known as the grounding zone. We also want to see new science that weve never imagined, because humans are creative and break through the limits of data, she said. (Vicky)