Low earth orbit is filled with all kinds of rubbish, which has brought a serious threat to the space missions.
Bolden Charles, an executive at NASA, said on Thursday that more countries will need to be added to the list of space junk, and to invest in space. All kinds of objects are now filled with the earth's orbit, and there is no space shuttle, abandoned, and debris, and they rotate around the earth at a speed of 17500 miles per hour.
The relevant departments of the U.S. Department of defense have been traced to 23000 objects in low earth orbit. NASA officials estimated that about 50 million larger than marbles of space junk is around the earth in moving, and there are likely to be more than 100 million paint spot size of tiny fragments.
The space junk into the earth's atmosphere last Friday was known as WT1190F, experts have predicted that the unknown object will be in the eastern United States to enter the earth's atmosphere at 1:20 a.m.. They predict it will land in the distance Sri Lanka about 62 miles of the Indian Ocean, but its real impact point experts in fact before is uncertain.
Bolden's statement is more about the mission of Mars, his dream is to send the astronauts to the asteroid in the 2020's, and then in the 2030's landing on mars. Although he did not provide any new information, but he is more likely to send people to Mars, rather than the current use of probes to explore the views of mars. He believes that robots can not make a reasonable choice as human beings.