Space is where our future is—trips to the Moon, Mars and beyond. Most people would think that aside from comets (彗星) and stars, there was little else out there. But, since our space journey started we have left so much trash there that scientists are now concerned that if we don’t clean it up, we may all be in mortal (致命的) danger.
The first piece of space junk was created in 1964, when the American satellite Vanguard 1 stopped operating and lost its connection with the ground center. However, since it kept orbiting around the Earth without any consequences, scientists became increasingly comfortable abandoning things that no longer served any useful purpose in space.
It is estimated that there are now over millions of pieces of man-made trash orbiting the Earth at high speed. The junk varies from tiny pieces of paint chipped off rockets to cameras, huge fuel tanks, and even odd items like the million-dollar tool kit that astronaut Heidemarie Stefanyshyn-Piper lost during a spacewalk.
The major problem with the space trash is that it may hit working satellites and damage traveling spacecraft. Moreover, pieces of junk may collide (碰撞) with each other and break into pieces which fall back to the Earth. To avoid this, scientists have invented several ways of clearing the sky. Ground stations have been built to monitor larger pieces of space trash to prevent them from crashing into working satellites or space shuttles. Future plans include a cooperative effort among many nations to stop littering in space and to clean up the trash already there.
【小题1】What was the first piece of man-made space trash?A.A camera. | B.A tool kit. |
C.A broken satellite. | D.A fuel tank. |
A.It did not cause any problems. |
B.It no longer served any useful purpose. |
C.It was millions of miles away from the Earth. |
D.It was regarded as similar to comets and stars. |
A.It is huge, heavy machines. |
B.It may cause problems for space shuttles. |
C.It floats slowly around the Earth. |
D.It never changes positions. |
A.Ground stations are built to help store the trash properly in space. |
B.Many nations have worked together to stop polluting space. |
C.Larger pieces of space trash are being closely watched. |
D.Scientists have cleaned up most of the trash. |