Astronauts begin complex fix for cosmic ray detector
CAPE CANAVERAL — Astronauts opened an extraordinarily complicated series of spacewalks Friday to fix a cosmic ray detector at the International Space Station.
Armed with dozens of dissecting tools, Italian astronaut Luca Parmitano removed a protective shield to gain access to the inside of the Alpha Magnetic Spectrometer. He handed the 4footlong panel to his spacewalking partner, American Andrew Morgan, for tossing overboard.
“OK, 321, release,” Morgan said as he let go of the shield high above the Pacific. This latest piece of space junk poses no danger to the orbiting lab, according to NASA. The 20pound panel should remain in orbit a year or so before reentering the atmosphere and burning up.
NASA considers these spacewalks the most difficult since the Hubble Space Telescope repairs a few decades ago. Unlike Hubble, the spectrometer was never meant to undergo space surgery. After 8½ years in orbit, its cooling system is almost dead.
Parmitano and Morgan will go out at least four times this month and next to revitalize the instrument.
Delivered to orbit by Endeavour in 2011 on the nexttolast space shuttle flight, the $2 billion spectrometer is hunting for elusive antimatter and dark matter. It has already studied more than 148 billion charged cosmic rays. That’s more than what was collected in over a century by highaltitude balloons and small satellites, said lead scientist Samuel Ting, a Nobel laureate at the Massachusetts Institute of Technology.