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Shuttle status check
Space shuttle program manager Wayne Hale and launch director Mike Leinbach hold this news conference May 31 from Kennedy Space Center to offer a status report on STS-121 mission preparations. The briefing was held at the conclusion of the debris verification review, which examined the external fuel tank and threats to the shuttle from impacts during launch.
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STS-29: Tracking station in the sky
NASA created its Tracking and Data Relay Satellite (TDRS) system to serve as a constellation of orbiting spacecraft that would replace the costly ground tracking stations scattered around the globe for communications with space shuttles and other satellites. Space shuttle Discovery's STS-29 mission in March 1989 launched the massive TDRS-D craft. This post-flight film narrated by the crew shows the deployment, the astronauts running a series of medical tests and the monitoring of a student-developed chicken embryo experiment.
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STS-61C crew film
Space shuttle Columbia began mission STS-61C with a beautiful sunrise launch in January 1986 after several delays. Led by commander Hoot Gibson, the astronauts deployed a commercial communications satellite and tended to numerous experiments with the Materials Science Laboratory, Hitchhiker platform and Getaway Special Canisters in the payload bay. The crew included Congressman Bill Nelson of Florida, the first U.S. Representative to fly in space. Watch this post-flight film narrated by the astronauts.
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Delta 4 launches GOES
The Boeing Delta 4 rocket launches from pad 37B at Cape Canaveral Air Force Station with the GOES-N spacecraft, beginning a new era in weather observing for the Americas.
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Discovery goes to pad
As night fell over Kennedy Space Center on May 19, space shuttle Discovery reached launch pad 39B to complete the slow journey from the Vehicle Assembly Building. Discovery will be traveling much faster in a few weeks when it blasts off to the International Space Station.
Full coverage
STS-61B: Building structures in orbit
The November 1985 flight of space shuttle Atlantis began with a rare nighttime blastoff. The seven-member crew, including a Mexican payload specialist, spent a week in orbit deploying three communications satellites for Australia, Mexico and the U.S. And a pair of high-visibility spacewalks were performed to demonstrate techniques for building large structures in space. The crew narrates the highlights of STS-61B in this post-flight crew film presentation.
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Study: 'Planemos' may spawn planets and moons
UNIVERSITY OF TORONTO NEWS RELEASE Posted: June 5, 2006
Forget our traditional ideas of where a planetary system forms - new research led by a University of Toronto astronomer reveals that planetary nurseries can exist not only around stars but also around objects that are themselves not much heftier than Jupiter. It suggests that miniature versions of the solar system may circle objects that are some 100 times less massive than our sun.
Credit: Art by www.jonlomberg.com
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That's the dramatic conclusion of two studies being presented Monday, June 5
at the American Astronomical Society meeting in Calgary by Professor Ray
Jayawardhana and his colleagues. The new findings show that objects only a
few times more massive than Jupiter are born with disks of dust and gas,
the raw material for planet making. Research done by Jayawardhana's group
and others in recent years had shown that disks are common around failed
stars known as "brown dwarfs". Now, they report, the same appears to be
true for their even punier cousins, sometimes called planetary mass objects or
"planemos." These objects, discovered within the past five years, have
masses similar to those of extra-solar planets, but they are not in orbit
around stars - instead, they float freely through space.
"Now that we've discovered these planetary mass objects with their own
little infant planetary systems, the definition of the word 'planet' has
blurred even more," says Jayawardhana, an associate professor of astronomy
and astrophysics. "In a way, the new discoveries are not too surprising -
after all, Jupiter must have been born with its own disk, out of which
its moons formed."
Unlike Jupiter, however, these planemos are not circling stars. In the
first study, Jayawardhana and Valentin Ivanov of the European Southern
Observatory (ESO) in Chile used two of ESO's telescopes - the 8.2-metre Very
Large Telescope and the 3.5-metre New Technology Telescope - to obtain optical
spectra of six candidates identified recently by researchers at the
University of Texas at Austin. Two of the six turned out to have masses
between five to 10 times that of Jupiter while two others are a tad heftier,
at 10 to 15 times Jupiter's mass. All four of these objects are just a few
million years old and are located in star-forming regions about 450
light-years from Earth. The planemos show infrared emission from dusty disks
that may evolve into miniature planetary systems over time.
In the other study, Jayawardhana and colleagues Subhanjoy Mohanty and Eric
Mamajek of the Harvard-Smithsonian Center for Astrophysics and Nuria Huelamo
of ESO used the Very Large Telescope to obtain infrared images and spectra
of a planetary mass companion discovered two years ago around a young brown
dwarf that is itself about 25 times the mass of Jupiter. The brown dwarf,
dubbed 2M1207 for short and located 170 light-years from Earth, was known to
be surrounded by a disk. Now, this team has found evidence for a disk around
the eight-Jupiter-mass companion as well. Researchers think the pair
probably formed together, just like a binary star system, instead of the
companion forming in a disk around the brown dwarf. Moreover, Jayawardhana
says, it is quite likely that smaller planets or moons could now form
in the disk around each one.
Both sets of discoveries point to objects not much more massive than Jupiter
forming the same way as stars like the sun, and perhaps being accompanied by
their own retinues of small planets. "The diversity of worlds out there is
truly remarkable," Jayawardhana adds. "Nature often seems more prolific than
our imagination."
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