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According to the Union of Concerned Scientists, there are nearly 2,800 working satellites in space. We depend on these devices for technology we use every day, such as video calls, online maps, satellite TV, and weather tracking. Scientists use them to study space and learn more about our planet.
But there are many other satellites in orbit that are no longer working. They’re among the objects cluttering up space. Some of these eventually fall back toward Earth, either landing or burning up in the atmosphere. But much of this space junk circles Earth for decades.
Orbital debris, a type of space junk, is any human-made object that has stopped working but continues to float around the Earth. This includes abandoned satellites and pieces of spacecraft, such as rocket stages.
Space junk also includes fragments of objects. These occur when satellites collide with things. They also result from an object crashing into an old rocket stage that still contains fuel, causing an explosion.
Heather Cowardin works at NASA. She says the United States is tracking more than 23,000 pieces of space debris. These tiny fragments can damage working satellites, which can affect research in space. That’s why cleanup efforts are so important.
(Karena Phan. www.timeforkids.com, 16.10.2020. Adaptado.)
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