The National Aeronautics and Space Administration has cleared space shuttle Discovery to return to Earth next week, deciding against sending astronauts for another spacewalk to repair a torn thermal blanket near a cockpit window.
Mission Control informed the astronauts that shuttle managers had reached the decision on Thursday during a meeting that a fourth spacewalk to deal with a puffed out thermal blanket is unnecessary.
"There is no issue," said Mission Control's Julie Payette, speaking to the crew.
The conclusion was reached after several wind tunnel tests and other engineering experiments determined the blanket did not pose a hazard during re-entry.
Wind tunnel tests overnight at NASA's Ames Research Centre in California showed little chance of any significant debris coming from the blanket at supersonic speeds. Further engineering analysis showed any debris released from the blanket was unlikely to hit structures on Discovery.
The Mission Management Team decision put to rest the work that was being done to assess the health of the thermal protection system. The tiles and reinforced carbon-carbon on Discovery's wings and nose were cleared earlier for entry.
Discovery and International Space Station crew members on Thursday delivered a moving tribute to the Columbia crew, including India-born Kalpana Chawla, and others, astronauts who lost their lives in the human exploration of space.