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STS-1: America's first space shuttle mission
The space shuttle era was born on April 12, 1981 when astronauts John Young and Bob Crippen rode Columbia into Earth orbit from Kennedy Space Center's launch pad 39A. The two-day flight proved the shuttle could get into space as a rocket and return safely with a runway landing. Following the voyage of STS-1, the two astronauts narrated this film of the mission highlights and told some of their personal thoughts on the flight.

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NASA's 2007 budget
NASA Administrator Mike Griffin, along with his science, spaceflight, exploration and aeronautics chiefs, hold this news conference in Washington on February 6 to discuss the agency's proposed budget for Fiscal Year 2007. The budget would give NASA a slight increase in funding over 2006, but it features cuts in some projects to pay for funding shortfalls in the shuttle program.

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Suit tossed overboard
The Expedition 12 crew tosses overboard an old Russian spacesuit loaded with ham radio gear during a spacewalk outside the International Space Station. The eery view of the lifeless suit tumbling into the darkness of space was captured by station cameras.

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STS-95: John Glenn's return to space
The flight of shuttle Discovery in October 1998 captured the public's attention with the triumphant return to space by John Glenn. The legendary astronaut became the first American to orbit the Earth some 36 years earlier. His 9-day shuttle mission focused on science experiments about aging. This post-flight presentation of highlights from the STS-95 mission is narrated by the astronauts.

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STS-71: First Mir docking
Space shuttle Atlantis and a multinational crew flew to the Russian space station Mir in June 1995 for the first in a series of joint docking missions, launching a new era of cooperation in space between the United States and Russia that would pave the way for the International Space Station. This post-flight presentation of highlights from the historic STS-71 mission is narrated by the astronauts.

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Challenger anniversary
On the 20th anniversary of the space shuttle Challenger tragedy, a memorial service was held at the Kennedy Space Center's Space Mirror. Speakers at the tribute to honor the lost Challenger, Columbia and Apollo 1 astronauts included the widow and son of Challenger commander Francis "Dick" Scobee, officials with the Astronauts Memorial Foundation, two local U.S. Representatives, commander of the first shuttle flight after Challenger and the Kennedy Space Center director.

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Future Mars rover
NASA's next mobile rover that will be sent to the Red Planet is Mars Science Laboratory. Roughly the size of a Mini Cooper car and designed to operate on the Martian surface for two Earth years, this large rover is scheduled for launch in 2009. Project manager Richard Cook unveils a model of the rover and talks about the mission in this video clip.

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Mars rover anniversary
The remarkable rovers Spirit and Opportunity remain alive and well on the surface of the Red Planet, far outlasting their planned 90-day missions. On Jan. 24, the second anniversary of Opportunity's landing, project officials and scientists held this celebration event at the Jet Propulsion Laboratory.

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Launch of New Horizons
The New Horizons spacecraft begins a voyage across the solar system to explore Pluto and beyond with its successful launch January 19 aboard a Lockheed Martin Atlas 5 rocket from Cape Canaveral, Florida.

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Stardust comes home
NASA's Stardust spacecraft returns samples of cometary dust to Earth with its safe landing in Utah on January 15.

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NASA administrator
NASA Administrator Mike Griffin and his deputy Shana Dale hold a news conference at Kennedy Space Center in the final hours of the countdown to the New Horizons launch. Questions from reporters ranged from the Pluto-bound mission, the agency's budget and the space shuttle program.

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How to steal a million stars?
Posted: February 11, 2006

Based on observations with European Southern Observatory's Very Large Telescope, a team of Italian astronomers reports that the stellar cluster Messier 12 must have lost to our Milky Way galaxy close to one million low-mass stars.

This photo shows the centre of the globular cluster Messier 12 as observed with the FORS-1 multi-mode instrument on ESO's Very Large Telescope. Credit: ESO
"In the solar neighbourhood and in most stellar clusters, the least massive stars are the most common, and by far", said Guido De Marchi (ESA), lead author of the study. "Our observations with ESO's VLT show this is not the case for Messier 12".

The team, which also includes Luigi Pulone and Francesco Paresce (INAF, Italy), measured the brightness and colours of more than 16,000 stars within the globular cluster Messier 12 with the FORS1 multi-mode instrument attached to one of the Unit Telescopes of ESO's VLT at Cerro Paranal (Chile). The astronomers could study stars that are 40 million times fainter than what the unaided eye can see (magnitude 25).

Messier 12 is one of about 200 globular clusters known in our Galaxy. These are large groupings of 10,000 to more than a million stars that were formed together in the youth of the Milky Way, about 12 to 13 billion years ago. Globular clusters are a key tool for astronomers, because all the stars in a globular cluster share a common history. They were all born together, at the same time and place, and only differ from one another in their mass. By accurately measuring the brightness of the stars, astronomers can determine their relative sizes and stage of evolution precisely. Globular clusters are thus very helpful for testing theories of how stars evolve.

An artist's impression of the orbit of the globular cluster Messier 12 in the Milky Way. Due to gravitational disruption, this cluster continuously loses stars, in particular light ones. This process is enhanced when it passes through the central plane in which most of the Galaxy's stars and nebulae are located. The cluster emerges in a less dense state after such a passage. The stars that are lost move on in orbits similar to that of the cluster and populate the halo of the Milky Way. Credit: ESO
Located at a distance of 23,000 light years in the constellation Ophiuchus (The Serpent-holder), Messier 12 got its name by being the 12th entry in the catalogue of nebulous objects compiled in 1774 by French astronomer and comet chaser Charles Messier. It is also known to astronomers as NGC 6218 and contains about 200 000 stars, most of them having a mass between 20 and 80 percent of the mass of the Sun.

"It is however clear that Messier 12 is surprisingly devoid of low- mass stars", said De Marchi. "For each solar-like star, we would expect roughly four times as many stars with half that mass. Our VLT observations only show an equal number of stars of different masses."

Globular clusters move in extended elliptical orbits that periodically take them through the densely populated regions of our Galaxy, the plane, then high above and below, in the ‘halo'. When venturing too close to the innermost and denser regions of the Milky Way, the ‘bulge', a globular cluster can be perturbed, the smallest stars being ripped away.

"We estimate that Messier 12 lost four times as many stars as it still has", said Francesco Paresce. "That is, roughly one million stars must have been ejected into the halo of our Milky Way".

The total remaining lifetime of Messier 12 is predicted to be about 4.5 billion years, i.e. about a third of its present age. This is very short compared to the typical expected globular cluster's lifetime, which is about 30 billion years.

The same team of astronomers had found in 1999, another example of a globular cluster that lost a large fraction of its original content.

The scientists hope to discover and study many more clusters like these, since catching clusters while being disrupted should clarify the dynamics of the process that shaped the halo of our home galaxy, the Milky Way.



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