sábado, 18 de agosto de 2007

A NASA vai fazer regressar o Endeavour mais cedo por causa do furacão 'Dean'

Com a aproximação do furacão 'Dean', e a possibilidade de ter de evacuar o Centro Espacial da NASA em Houston, de onde são controlados os vôos espaciais, foi decidido abreviar a última saída dos astronautas para o exterior da ISS, por forma a possibilitar o fecho das escotilhas que ligam o Shuttle à ISS ainda hoje, por volta das 10:00 da noite, hora de Lisboa. Isto para permitir a separação do Shuttle amanhã, para aterrar na Terça-feira. A hora prevista para a primeira tentativa de aterragem será por volta das 5:30 da tarde, hora de Lisboa.

Na sua última saída para o exterior, os astronautas aproveitaram para tirar uma espetacular foto ao furacão 'Dean' (acima).

Astronauts complete spacewalk
Hurricane Dean prompts NASA to shorten job
The Associated Press
Updated: 3:14 p.m. ET Aug. 18, 2007

HOUSTON - Astronauts hurriedly completed space station maintenance work Saturday in a spacewalk that was shortened to save time in case NASA moved up Endeavour’s departure and ordered the shuttle to land a day early because of Hurricane Dean.

NASA feared the hurricane might veer toward Houston, home of Mission Control, forcing an emergency relocation of flight controllers to Cape Canaveral. The makeshift control center there would not be nearly as good or big as the Houston operation, and that’s why managers were leaning toward bringing Endeavour back to Earth as soon as possible.

In that case, Endeavour would undock from the international space station on Sunday and land Tuesday. As of Saturday afternoon, however, the undocking was still set for Monday, with a touchdown two days later.

Hurricane Dean, a fierce Category 4, was headed toward Mexico’s Yucatan Peninsula and the Gulf of Mexico. It was uncertain whether the storm might strike the Texas coastline late in the week; that uncertainty made NASA’s decision — so many days in advance — all the harder.

Spacewalkers Dave Williams and Clay Anderson could see the eye of the giant hurricane as the shuttle-station complex orbited 214 miles above the Caribbean, exclaiming “oh wow” and “holy smokes.” “Hooo, man, yeah, can’t miss that,” one of them said.

Williams and Anderson tackled only the most important chores that had been planned for the fourth and final spacewalk of Endeavour’s mission. Mission Control cut two hours from the spacewalkers’ to-do list so the hatches between the linked spacecraft could be closed late Saturday afternoon in preparation for a possibly hastened undocking.

The two men attached a stand to the station’s’ exterior for a shuttle inspection boom. The stand won’t be used until next year. They also retrieved two experiments from the outside of the station for return to Earth, and hooked up antenna equipment.

Three hours into the five-hour spacewalk, a fire alarm sounded inside the station, its shrill beeps loud enough to be heard over the radio loops. The station crew rushed to check, but could find no evidence of smoke and Mission Control quickly confirmed it was a false alarm. As it turns out, the same alarm acted up a few weeks ago.

The brief interruption did not affect the spacewalk.

The spacewalkers’ gloves, meanwhile, held up just fine. The previous spacewalk was cut short after one astronaut ripped his glove. As a precaution, Williams and Anderson frequently checked their gloves and stayed clear of sharp edges.

“My gloves look like they just came off the showroom floor,” Anderson said as the spacewalk ended.

NASA’s hurricane deliberations followed almost immediately on the heels of the decision to forgo shuttle repairs.

Late Thursday, mission managers concluded that a deep gouge on Endeavour’s belly posed no Columbia-like threat to the seven crew members during re-entry and also would not lead to lengthy postflight shuttle repairs. For a week, managers had considered sending two astronauts out with black protective paint and untested goo to patch the 3½-inch-long, 2-inch-wide gouge that dug all the way through the thermal tiles.

The gouge was caused by debris that broke off a bracket on Endeavour’s external fuel tank during liftoff Aug. 8. Engineers still do not know whether it was foam insulation, ice or a combination of both. In any case, NASA said it will not launch another shuttle until the longtime troublesome brackets are fixed.

Endeavour’s crew includes teacher-astronaut Barbara Morgan, who was Christa McAuliffe’s backup for Challenger’s tragic 1986 flight.


E da CBS:

Update: Astronauts marvel at Hurricane Dean; wrap up abbreviated spacewalk
2:25 PM, 8/18/07,

Canadian astronaut Dave Williams and space station flight engineer Clay Anderson staged an abbreviated fourth and final spacewalk today, pausing for a moment to take in a spectacular bird's eye view of Hurricane Dean, the storm that prompted NASA managers to make preparations for an earlier-than-planned undocking and landing.

The spacewalk began at 9:17 a.m. and ended at 2:19 p.m. for a duration of five hours and two minutes. Williams, Anderson and shuttle astronaut Rick Mastracchio logged a total of 23 hours and 15 minutes of spacewalk time across four outings during Endeavour's mission. This was the 92nd spacewalk since station construction began in 1998 and the 15th so far this year. Total station assembly EVA time now stands at 567 hours and 59 minutes.

Concerned about the possibility of an evacuation that could force NASA to move mission control from Houston to more limited facilities at the Kennedy Space Center in Florida, NASA managers told the astronauts to shave two hours off today's spacewalk as part of a plan to preserve the option of undocking early Sunday and landing Tuesday, a day ahead of schedule.

By shortening today's spacewalk, the astronauts can make final equipment transfers and close the hatches between Endeavour and the space station around 5 p.m., setting the stage for undocking Sunday. NASA's Mission Management Team planned to review the forecast during an afternoon meeting and make a decision about how to proceed after hatch closure.

Williams and Anderson accomplished three primary objectives during today's spacewalk. They installed clamps on the station's main solar array truss that will be used next year to temporarily hold a shuttle heat shield inspection boom; Anderson retrieved two space exposure experiments while Williams adjusted an antenna gimbal lock assembly. After that, the spacewalkers worked together to install a wireless instrumentation antenna on the Destiny laboratory module. Deferred to a future spacewalk was work to tie down debris shields on Destiny and the multi-hatch Unity connecting module.

As they worked to install the wireless antenna, the space station sailed 214 miles above Hurricane Dean.

"Oh, wow!" one of the astronauts - presumably Williams - exclaimed as he caught sight of the huge storm. "Oooo man, can't miss that!"

"Holy smoke," Anderson said. Television views from the station showed the hurricane in its entirety, sporting a tight, well-defined eye at the heart of of the storm.

"That's impressive," Williams said.

"Can you see the eye?"

"Oh yeah," Williams said. "Definitely."

"Oh yeah, that's wild," Anderson said. "All right, Dave, I'm going to put another tether on there before I hand it to you."

"Copy that," Williams said as the two spacewalkers continued work to install a wireless instrumentation antenna. "Man, that's impressive."

"Very," Anderson agreed, adding: "They're only impressive when they're not coming to you."

"That's true."

Williams, Mastracchio, Endeavour commander Scott Kelly, pilot Charles Hobaugh, Tracy Caldwell, Al Drew and educator-astronaut Barbara Morgan plan to say goodbye to their space station colleagues - Expedition 15 commander Fyodor Yurchikhin, Oleg Kotov and Anderson - during a brief farewell ceremony in the Destiny laboratory module around 4:46 p.m. Hatches between the two spacecraft are expected to be closed about 15 minutes later. Today's mission status briefing is scheduled to begin at roughly the same time and this status report will be updated as soon as possible thereafter.

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