For the first time, an experimental treatment made from human embryonic stem cells has shown evidence of helping someone, partly restoring sight to two people suffering from slowly progressing forms of blindness.CAPE CANAVERAL, Fla. – Spacewalking astronauts installed a new coolant pump for the international space station Monday, accomplishing urgent cooling-system repairs after more than two weeks of impaired operations in orbit.
Initial tests showed the ammonia pump was operating well, although flight controllers still have more checks to make.
If everything goes well, NASA expects to have the space station’s disabled cooling loop back in action and everything working normally within a few days.
“We’re going to have a lot cooler station here shortly,” promised Mission Control.
The orbiting lab has been operating on half its normal cooling capability since the pump failed July 31, forcing the six-person crew to shut down science projects and turn off unnecessary equipment to avoid overtaxing the single functioning cooling line. But living conditions never deteriorated.
Douglas Wheelock and Tracy Caldwell Dyson spent nearly 23 hours on emergency spacewalking repairs, conducting three outings in just 10 days.
Unlike the first two spacewalks, Monday’s seven-hour, 20-minute excursion unfolded almost perfectly.
To everyone’s relief, the work went smoothly, with no apparent leakage of the toxic substance. On the first spacewalk, ammonia streamed out and forced NASA to add an extra outing to get the job done.
