Spacewalking astronauts installed new pumps on a cosmic ray detector outside the International Space Station on Monday in a bid to extend its scientific life.
It was the third spacewalk in nearly three weeks for Italy's Luca Parmitano and NASA's Andrew Morgan. One more spacewalk remains before NASA can declare the Alpha Magnetic Spectrometer successfully repaired.
The $2 billion spectrometer has been up there hunting for antimatter and dark matter for 8 ½ years, longer than anticipated. Without four new pumps for cooling, the device would be crippled and, ultimately, useless.
The Alpha Magnetic Spectrometer has been hunting for antimatter and dark matter for 8 ½ years.
NASA compared the series of four spacewalks " the most complex since the Hubble Space Telescope missions " with heart bypass surgery because they are designed to bypass the old, degraded pumps.
The $2 billion spectrometer was never meant for hands-on repairs like this and was designed to last just three years. If the new plumbing holds, the instrument should last the entire life of the space station, or another five to 10 years.
Given the high stakes, Mission Control urged the spacewalkers to "take good care" of the pumps. Parmitano clutched the 159-kilogram box of pumps, a bulky 107 centimetres by 82 centimetres, with both hands as he headed toward the spectrometer.
Parmitano quickly attached the bundle to the spectrometer, then hooked up power and data cables. He crossed his gloved fingers as best he could " and his booted toes, too, he noted " as flight controllers switched on the power to the instrument. The instrument came alive.