Space Junk Threatens Earth’s Orbital Environment
19 September 2011
JIM TEDDER: This is SCENCE IN THE NEWS, in VOA Special English. I’m Jim Tedder.
KATHERINE COLE: And I’m Katherine Cole. Today, we tell about an ever increasing number of objects in low Earth orbit. We mark the twentieth anniversary of the launching of the Hubble Space Telescope. We also tell how islands off the coast of North Carolina help to protect the rest of North America from destructive storms.
(MUSIC)
JIM TEDDER: A camera, a glove, a hand tool, even a toothbrush…they are all up there, above the clouds, going around and around the Earth. There are also thousands of pieces of metal and plastic. Some of them are only about the size of a fingernail. Many are much larger. Scientists consider all these objects to be “space junk,” and they are a problem.
Since people first launched rockets into space in the nineteen-fifties, we have been leaving behind all sorts of things. Some of them, like the camera, were lost by astronauts while they did work outside their spacecraft. But much of the space junk is made up of little pieces of things that were once bigger objects, until they struck each other and broke apart.
This computer image of Earth shows orbiting layers of space junk being observed by NASA
KATHERINE COLE: Some things we send into space fall back toward Earth and burn up in the atmosphere. But larger pieces sometimes survive the extreme heat and hit the ground or the ocean at great speeds. So there is always concern that something may fall from the sky and do some harm.
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