quarta-feira, 24 de outubro de 2007

Vídeo do lançamento, ontem, do Space Shuttle Discovery

Esta será provavelmente a missão mais complexa de sempre. Será montado um novo módulo na Estação Espacial Internacional, e o tipo de trabalho que terá de ser feito é bastante intenso e complexo.

Durante a contagem decrescente houve vários problemas, e mesmo dúvidas acerca do lançamento, devido nomeadamente ao tempo que estava a piorar bastante próximo do momento do lançamento, e à detecção de gelo numa das condutas que alimentam o Shuttle de combustível - este problema tendo sido considerado MUITO GRAVE pela NASA. No entanto, a análise feita levou os responsáveis a concluir que não haveria perigo para o Shuttle durante o lançamento.

A missão está a correr bem, não tendo havido quase nenhuma queda de gelo a partir do grande tanque externo (côr de laranja), como infelizmente é costume nestas missões.

É a primeira vez que um Shuttle comandado por uma mulher vai ao encontro de uma Estação Espacial também comandada por uma mulher.

Outra curiosidade é a hora do lançamento ter coincidido exactamente com a hora de lançamento da última missão do Challenger.

Shuttle Discovery launched
02:30 PM, 10/23/07, Update:
(UPDATED at 3 p.m. with post-launch news conference; quotes and details; correcting time of docking)

The shuttle Discovery, carrying seven astronauts and a critical connecting module for the international space station, roared to life and rocketed into orbit today, kicking off a high-stakes five-spacewalk mission considered by many the most complex orbital construction work ever attempted.

"I don't think there's ever been an astronaut who doesn't consider their flight the most dramatic, exciting, complex mission ever," lead spacewalker Scott Parazynski said before launch. "But ours is!"

With its three hydrogen-fueled main engines roaring at full throttle, Discovery's twin solid-fuel boosters ignited with a rush of fire and thunder at 11:38:19 a.m., instantly pushing the huge spacecraft away from pad 39A.

Seconds later, Discovery's flight computers sent commands to the booster steering system, rolling the spacecraft about its vertical axis to put the crew in a heads down orientation as the spaceplane arced out over the Atlantic Ocean on a trajectory paralleling the East Coast of the United States.

NASA managers were worried early today about an ice buildup on an umbilical on the lower section of the shuttle's external fuel tank and by threatening weather. But as the morning wore on, the anticipated cloud development held off, engineers decided the ice would most likely shake off at launch and Discovery was cleared for flight.

"OK, Pambo, on behalf of your KSC family, I'd like to wish you good luck, Godspeed, have a little fun up there," Launch Director Mike Leinbach radioed the crew a few minutes before launch.

"Copy that, Mike," replied Melroy, the second woman to command a space shuttle. "We feel a tremendous amount of pride in the 10A and Discovery team and a lot of gratitude for the hard work to get us here. And we're ready to take Harmony to her new home."

Joining Melroy on Discovery's flight deck were Marine Corps pilot George Zamka, flight engineer Stephanie Wilson and Doug Wheelock, an Army helicopter pilot. Strapped in on the orbiter's lower deck were physician-astronaut Parazynski, Italian astronaut Paolo Nespoli and Dan Tani, a space station crew member hitching a ride to the lab complex aboard Discovery. Tani will replace station engineer Clay Anderson, who will return to Earth aboard the shuttle.

Television views from a camera mounted on Discovery's external fuel tank provided spectacular views of the Florida spaceport dropping away and then the limb of the Earth as the ship headed for orbit. Bill Gerstenmaier, chief of space flight operations for NASA, said a quick look at the video indicated about a half-dozen small pieces of foam insulation fell away from the shuttle's external tank during the climb to space.

But in all cases, Gerstenmaier said, the debris separated after Discovery's solid-fuel boosters were jettisoned and well beyond the regime in which the denser lower atmosphere can slow lightweight foam enough to cause impact damage when the shuttle runs into it at a high relative velocity.

"We took a quick look at the video and we saw probably six instances of foam loss off the tank and they were all after solid rocket booster separation," Gerstenmaier said. "So in that sense, they're not a concern from a damage-to-the-orbiter standpoint. ... We'll see when we get some good pictures of the external tank here later today or tomorrow."

While Gerstenmaier was addressing reporters at a post-launch news conference, astronaut Terry Virts in mission control at the Johnson Space Center in Houston, radioed Melroy with a debris update.

"Pam, there were several events noted during ascent," he said. "They occurred after the critical transport mach number. We will continue to look at it. This is just preliminary only, but it did look like a clean ascent. Also there was some ice on the aft LH2 (liquid hydrogen) lines on the tank, we saw that pre launch and it cleared right at T-0 as expected."

The astronauts photographed the tank shortly after it separated from the shuttle in orbit and Parazynski reported "no visible, at least to the naked eye, loss of big pieces of foam."

The crew will carry out a detailed inspection of the shuttle's nose cap and wing leading edge panels using a laser scanner and high-resolution camera on Wednesday while engineers on the ground continue analysis of long-range tracking camera and launch pad footage. In the meantime, NASA managers were thrilled with today 's launching.

"This is a great start to a very challenging mission in front of us," Gerstenmaier said. "If I look at this mission and what's coming up for us, we're combining, effectively, activities we've done on at least four other missions, all into one mission. So this is a pretty exciting mission. We're going to do a solar array deploy, a radiator deploy, a pressurized module addition, just a tremendous series of challenges in front of us.

"I think the teams are ready, really prepared for any eventualilty. ... I can't think of a better start to this mission than what we got today. So again, hats off to the KSC folks and the orbiter folks who gave us a great vehicle and a great ride to start a great mission."

Discovery took off at roughly the moment Earth's rotation carried the launch pad into the plane of the space station's orbit. If all goes well, Melroy will manually guide the shuttle to a linkup with the station around 8:35 a.m. Thursday.

Discovery's docking and the usual welcome aboard ceremony will have an unusual flavor this time around as Expedition 16 commander Peggy Whitson, the station's first female commander, welcomes Melroy, probably the final woman to command a shuttle before the program is retired in 2010. Both women flew together in 2002 when Whitson served as flight engineer of the fifth station expedition and Melroy visited as pilot of the shuttle Atlantis during mission STS-112.

"One of the moments I'm looking forward to the most is when the hatch opens and I see Peggy's face on the other side and we reach through for the traditional handshake," Melroy said in an interview. "That will be a really special moment for me."

Whitson said the timing of their flights was a coincidence, "but I do think it is special, not only special just for Pam and I because, you know, we have flown in space before, but the experience of having two women up there at the same time will hopefully be an inspiration to somebody."

"I was inspired when I was young by the Apollo era astronauts and in particular, I was motivated to become an astronaut when they selected the first female astronauts," she said. "I would hope that we could be a role model like that."

The day after docking, the astronauts will use the station's robot arm to pull the 31,500-pound Harmony module from Discovery's cargo bay as part of the first of the mission's five spacewalks.

Harmony will be temporarily mounted on the left side of the station's central Unity module. After the shuttle departs, Whitson, flight engineer Yuri Malenchenko and Tani will detach the station's main shuttle docking port, known as pressurized mating adapter No. 2, mount it on Harmony and then use the station's robot arm to move both components on the front end of the Destiny laboratory module.

Whitson and Tani plan to stage two spacewalks in November to connect Harmony to the station's cooling system and power grid to clear the way for launch of the European Space Agency's Columbus research lab aboard the shuttle Atlantis in December. Columbus will be attached to Harmony's right-side port while Japan's Kibo lab module will be connected to Harmony's left hatch next year.

"Harmony has six different ports that we can add modules onto to build the station," said Whitson. "So it's, it's our next big connecting piece in our puzzle of putting this huge station together on orbit."

Attaching a new pressurized module would have been the highlight of many past assembly missions. But for Discovery's crew, it is just the beginning. The second major objective of the flight is the disconnection and relocation of a huge set of solar arrays known as P6. Designed as the sixth and final segment of the port, or left, side of the station's main power truss, P6 was mounted at the center of the station in December 2000 to provide power to the U.S. segment during the initial stages of assembly.

Now, with identical solar panels in place on the left and right sides of the main power truss, NASA needs to move P6 to its permanent position on the far left end of the beam. The 35,000-pound segment's huge arrays, stretching 240 feet from tip to tip, were stowed during shuttle missions last December and June. Power and cooling lines were disconnected during an August flight, setting the stage for the massive truss's detachment, relocation and re-extension during Discovery's mission.

The station's robot arm cannot reach far enough on its own to make the move. So the station arm, after handing P6 off to the shuttle's space crane, will be moved by the station's mobile transporter to the far end of the power truss. At that point, the shuttle arm will hand the truss segment back to the station arm and Parazynski and Wheelock, making their third spacewalk by that point, will oversee its attachment to the P5 truss segment.

"Moving the P6 solar array will be a major activity," Melroy said in a NASA interview. "On our second spacewalk - our first spacewalk is all about (Harmony) - we'll be using the robotic arm in one location to actually reach around and pull P6 off ... with the assistance of our spacewalkers.

"Once the P6 has been detached from the space station, then the robotic arm will move it around to the port side of the shuttle, at which point it will be handed off to the shuttle arm. The shuttle robotic arm will take control of the P6 truss while the space station robotic arm is reconfigured and rolled out on the mobile transporter, the mobile platform, all the way to the far end of the port truss. And then, we'll use the station arm to take it back and install it in its final location.

"This is pretty nearly the design-limiting case for the robotic arm of the space station, so it's out at its full extension, trying to get that truss out there," Melroy said. "We'll have the help of the spacewalkers on the third spacewalk to do that. So, all these activities will actually span three days, three full days, two spacewalks with robotics in the middle."

Discovery is scheduled to land back at the Kennedy Space Center on Nov. 6.

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