THIS STORY HAS BEEN FORMATTED FOR EASY PRINTING

Astronauts fix 2d failed computer

NASA speculates cosmic radiation caused event

By Marcia Dunn
Associated Press / July 16, 2011

E-mail this article

Invalid E-mail address
Invalid E-mail address

Sending your article

Your article has been sent.

Text size +

CAPE CANAVERAL, Fla. - The pilots on NASA’s last space shuttle flight fixed another main computer yesterday after it failed and set off an alarm that shattered their sleep.

NASA declared all five of Atlantis’ primary computers to be working, pending evaluation of the latest shutdown.

Computer failures such as this are extremely rare in orbit, said lead flight director Kwatsi Alibaruho. The two problems appear to be quite different, he noted. The first was caused by a bad switch throw; the second possibly by cosmic radiation.

“The fact that we did have two computer failures on a same flight on a spacecraft that’s otherwise performing beautifully, that’s not at all lost on me,’’ Alibaruho said.

“I do have a saying that you’re not paranoid if they really are after you, so I am cautiously optimistic that we’ll have a healthy data-processing system’’ for Atlantis’s undocking and return to Earth next week, he added. “But we will be watching closely.’’

Atlantis’s commander, Christopher Ferguson, said the alarm sounded an hour or so after the four astronauts had gone to bed, during the deepest part of their sleep.

“We all woke up and looked at one another, and we were wondering really what was going on,’’ he said in an interview yesterday morning. The astronauts rushed to the flight deck and switched to a backup computer. Within a half-hour they were back in bed.

The first computer failure occurred just before Sunday’s docking by Atlantis to the international space station. New software loads took care of both problems, at least for now.

The five computers are critical for a space shuttle’s return to Earth - so crucial that multiple shutdowns, in certain circumstances, could prompt an early return home. Atlantis is due to make the last landing of the 30-year space shuttle era Thursday.

President Obama made note of the historic journey yesterday in a call from the Oval Office to space. He thanked everyone at NASA and the “thousands who have poured their hearts and souls into America’s shuttle program over the last three decades.’’

Ferguson told the president that the 10 space travelers will mark the occasion right before the hatches close between the two craft early next week. He will hand over a US flag that flew on the first shuttle flight in 1981 - and returned to orbit aboard Atlantis. The flag will remain aboard the outpost until Americans are launched again from US soil by one of the private companies competing to develop a spacecraft to replace the shuttle.