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Apollo 1 service
On the 40th anniversary of the Apollo 1 fire that took the lives of astronauts Gus Grissom, Ed White and Roger Chaffee, a remembrance service was held January 27 at the Kennedy Space Center's memorial Space Mirror.

 Part 1 | Part 2

Technical look at
Project Mercury

This documentary takes a look at the technical aspects of Project Mercury, including development of the capsule and the pioneering first manned flights of America's space program.

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Apollo 15: In the Mountains of the Moon
The voyage of Apollo 15 took man to the Hadley Rille area of the moon. Astronauts Dave Scott and Jim Irwin explored the region using a lunar rover, while Al Worden remained in orbit conducting observations. "Apollo 15: In the Mountains of the Moon" is a NASA film looking back at the 1971 flight.

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Skylab's first 40 days
Skylab, America's first space station, began with crippling problems created by an incident during its May 1973 launch. High temperatures and low power conditions aboard the orbital workshop forced engineers to devise corrective measures quickly. Astronauts Pete Conrad, Paul Weitz and Joe Kerwin flew to the station and implemented the repairs, rescuing the spacecraft's mission. This film tells the story of Skylab's first 40 days in space.

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Jupiter flyby preview
NASA's New Horizons space probe will fly past Jupiter in late February, using the giant planet's gravity as a sling-shot to bend the craft's trajectory and accelerate toward Pluto and the Kuiper Belt. Mission officials describe the science to be collected during the Jupiter encounter during this briefing.

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Supplies arrive at ISS
The 24th Russian Progress resupply ship sent to the International Space Station successfully makes the final approach and docking to the Pirs module of the outpost while running on automated controls.

 Rendezvous | Docking

Interview with teacher Barbara Morgan
Barbara Morgan, the former Idaho school teacher who served as Christa McAuliffe's backup for the Teacher in Space program, sits down for this NASA interview. As NASA's first Educator Astronaut, Morgan will be a mission specialist and robot arm operator during shuttle Endeavour's STS-118 flight to the space station, targeted for launch in June.

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The Flight of Sigma 7
On October 3, 1962, Wally Schirra became the fifth American to rocket into space. This NASA film entitled "The Flight of Sigma 7" explains the 9-hour voyage that gained important knowledge in the Mercury program.

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Spacewalking astronauts make station cooling changes
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: January 31, 2007

Space station commander Mike Lopez-Alegria and Sunita Williams successfully connected one of two critical ammonia coolant loops today during the first of two spacewalks devoted to switching the lab complex to its permanent cooling system.

It took the astronauts nearly three hours to disconnect and re-connect a variety of fluid lines to bypass an interim cooling system and route ammonia from the permanent system, mounted in the station's main solar array truss, to heat exchangers in the Destiny laboratory module.

Because ammonia is toxic, electronic gear in the lab is mounted on cold plates that use circulating water to carry away heat. The warmed water flows through heat exchangers that transfer the heat to ammonia that is pumped through external radiators.

Up until this point in the station's assembly, the heat exchangers were connected to a temporary ammonia cooling system that utilized radiators on the P6 solar array truss extending up from the Unity module.

But during the last shuttle mission in December, astronauts and flight controllers activated the station's permanent electrical system, along with big pumps, radiators and other equipment in the main solar array truss that make up the lab's two independent permanent cooling loops.

The P6 solar wings and radiators providing interim power and cooling up to this point will be moved to the left end of the solar array truss in September where it will become part of the permanent power system. The left wing of the P6 array was retracted in December and the starboard wing will be retracted during a shuttle mission in March.

During today's spacewalk, Lopez-Alegria and Williams, working in a cramped area known as the "rat's nest" between the lab module, Unity and the Z1 truss that supports the P6 solar array, disconnected four fluid lines that had been routing ammonia to the temporary cooling system and reconnected them to loop A of the permanent system.

Flight controllers reported good ammonia flow through Loop A and good temperatures after the reconfiguration "so you guys have been doing really good work," called spacewalk engineer Chris Looper from mission control. "I know it's been hard. It looked to me like access to those was actually tougher than it is in the NBL (spacewalk training pool), which is not really surprising. But I feel for you."

"Well thanks," Lopez-Alegria said. "You're right about that access. It's pretty abysmal."

The astronauts took great care making sure each quick-disconnect fitting was secure and leak free, pushing and pulling on the lines and securing thermal booties as required to maintain the proper temperature.

"OK, I see a good line on your latch," Lopez-Alegria said in a typical exchange.

"And I see a good line on yours," Williams confirmed.

"OK, and then a pull test, right?"

"That's affirmative, Mike," mission control replied. "A pull test and then the final will be to pull the bale aft and then full forward. That'll tell you you've got it on good."

"OK, that's complete."

The astronauts were strictly business as they worked through the long checklist with the only levity coming when Lopez-Alegria joked at one point, "OK, my bootie is open and bootie integrity is bootie-licious."

Because of problems with ammonia leakage during an earlier mission, the astronauts were prepared to carry out extensive spacesuit decontamination procedures to make sure no dangerous levels of ammonia could make it into the station's airlock and into the lab's air supply.

But to everyone's relief, there were no signs of leakage today and with the loop A connections complete, ground controllers geared up to retract one of the three radiators on the P6 array. Lopez-Alegria and Williams will lock the radiator down and install a thermal cover before moving on to a few final items if time allows.

Three hours into the spacewalk, they were about 50 minutes behind schedule.

"We didn't have any ammonia leaks, though," Williams observed.

"Boy, we are thankful for that," Looper replied. "We're confident we're going to finish all our nominal tasks in the time that we have remaining. So everybody's feeling good about it up here."

"Us too, Chris," said Lopez-Alegria. "It was worth it taking our time."