91色情片

A US military satellite has traced a cloud of orbiting space dust back to a
Chinese rocket which exploded on 11 March. This is the first time anyone has
managed to trace space dust back to its source, says Nicholas Johnson of NASA鈥檚
Johnson Space Center. About ten times the normal rate of impacts from particles
4 to 15 micrometres across were recorded by the satellite over eight days at the
end of March. The impacts happened as it passed near the orbit previously
occupied by the 1-tonne final stage of China鈥檚 Long March 4 rocket.