NASA's Earth Resources 2 jet, also known as the ER-2, is a repurposed U-2 spy plane that is now used for scientific research purposes. The ER-2 is able to fly into the lower stratosphere at subsonic speeds, making it useful for studying hurricanes, testing satellite systems, and other scientific research. NASA has used the ER-2 to study everything from global warming to ozone depletion, and it is able to test out sensors that scientists want to use on satellites, which allows them to find and address any bugs in the system without the cost of launching a faulty satellite into space. The ER-2 is also able to fly at high altitudes, making it a useful tool for studying the forces of nature. Science continues to amaze!
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