The amount of space junks floating in Earth\'s orbit has reached a critical level, warned scientists. The future space missions may become too dangerous to fly for a risk of colliding with space junks, said a report released recently by the U.S. National Research Council (NRC). The kinds of space junks range from huge, the report said, there are thousands of discarded satellites and rocket boosters and countless tiny pieces of daily gabages from space missions. The debris are traveling in orbit at 17,500mph, at such a speed even a tiny clash can destroy a spacecraft. The NRC recommended that NASA should launch a plan to clean up the floating debris and called on other major space nations\' cooperation. \"The current space environment is growing increasingly hazardous to spacecraft and astronauts,\" said Kessler, an ex-NASA researcher, \"NASA needs to determine the best path forward for tackling the multifaceted problems caused by meteoroids and orbital debris that put human and robotic space operations at risk.\"