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Atlantis rollover
Space shuttle Atlantis emerges from its processing hangar at dawn February 7 for the short trip to the Vehicle Assembly Building at Kennedy Space Center's Complex 39.

 Leaving hangar | To VAB

Time-lapse movies:
 Pulling in | Sling

Microgravity laboratory
Shuttle Columbia carried the first United States Microgravity Laboratory during its summer 1992 flight to orbit. The Spacelab science expedition was the longest shuttle mission to date, thanks to the new Extended Duration Orbiter equipment flown for the first time. The crew of STS-50 narrate the highlights in this post-flight film.

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Research Project: X-15
The documentary "Research Project: X-15" looks at the rocketplane program that flew to the edge of space in the effort to learn about the human ability to fly at great speeds and aircraft design to sustain such flights.

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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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Planetary scientist says: Focus on Europa
WASHINGTON UNIVERSITY IN ST. LOUIS NEWS RELEASE
Posted: February 14, 2007

Yogi Berra supposedly suggested that when you come to a fork in the road, you are supposed to take it.

That's just what planetary scientists studying the rich data set from the Galileo Mission to the outer solar system are doing now. They're taking the fork.

According to William B. McKinnon, Ph.D., professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, the community suffers from an embarrassment of riches, because each of the moons of Jupiter differs in the way that they can reveal more about planets and how they behave. But he thinks it is Europa that clearly commands the most attention.

There are four large, moons of Jupiter that in their character and behavior are more like planets than Earth's moon: Io, Europa, Ganymede and Callisto. The last three are icy.

Io's volcanic hyperactivity is well known, but there are mysteries about the temperature of its magmas and its spectacular mountains and what they might reveal about the satellite's interior processes. As for the exterior moon Callisto, how did it acquire an ocean yet not be deeply differentiated? Ganymede's liquid iron core is still generating a magnetic field. This was not predicted beforehand, and thus has much to teach planetary scientists on how magnetic fields are generated in the solar system. Then, there is Europa.

"Of the four Galilean moons, Europa is the one that has the best chance to reveal the most about the origin of life, which is the biggest unanswered scientific question we have, bar none," he said. "With its massive body of liquid water, multiple energy sources proposed and different ways to provide carbon and other biogenic elements, the central question must be Europa's potential for life. What greater question can you ask of a planet?"

McKinnon reviewed each of the moons and their unanswered questions in his invited talk, "O Sister, Where Art Thou? The Galilean Satellites After Galileo," presented at the Fall 2006 meeting of the American Geophysical Union held Dec. 10-15, 2006, in San Francisco. All but Ganymede, a young male, are named after female Greek mythological characters. Thus, McKinnon refers to Ganymede as an honorary sister.

"Europa has been recently geologically active, but because Galileo's main antenna did not unfurl, we did not take enough images to catch any active geysering, such as seen on Saturn's itsy bitsy icy moon, Enceladus," McKinnon said. "Europa's surface appears very young and there are lots of interesting ice tectonics, and surface eruptions with weird colors and spectral signatures whose compositional implications everyone just loves to argue about."

'Capped' ocean

All the accumulated evidence points to an ocean under a global shell of ice, an ocean lying no more than 10 to 20 kilometers below Europa's airless surface, McKinnon said.

"That sounds really deep to a person with a pick ax, or even a drilling rig, but in geologic terms it's really pretty close," he said. "It's basically a capped ocean. "

The existence of the ocean is related to the great amount of heat coming up from Europa's interior.

"If you look at the surface and how deformed it is, you can tell the ice shell is relatively thin and really has been active in recent geological time, indeed is probably active today," McKinnon said.

Europa has a few, but not many, impact craters, also indicating its relative youth.

Europa's ocean begs to be studied, McKinnon said, as do the strikingly colored surface materials that Galileo images captured.

"To go into orbit around Europa with high-resolution cameras, spectral imagers and sophisticated, ice-penetrating radars of the sort mapping Mars right now, would allow us to really characterize that ocean and give us clues about the biogenic potential of the surface materials, "McKinnon said. "We'd see to the bottom of the ice shell, I predict. It would be a fantastic proof of concept."

A mission to Europa is feasible, McKinnon said. It would take about 10 years if started today (six of those years being spent in reaching the satellite). And it would be expensive, "about two billion dollars, give or take," he added.

"It would also have to compete for funds with NASA's plans to establish a Moon base," he said. "The Europeans are interested as well, so maybe we could cooperate and share the cost."

NASA has committees exploring a number of options, McKinnon said, and they include returning to Europa or Titan after the conclusion of the Cassini mission or perhaps returning to the little active moon around Saturn, Enceladus.

"It's a tiny moon, but it has an active plume that, because of that moon's very low gravity, extends well out into space, so you can just fly right through it," McKinnon said. "That's a nifty way to go sampling."

Of course, Europa is a much bigger target to explore.

"It has 40 times the surface area of Enceladus ‹ there's a lot more there there," he concluded.