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Supply ship docking
The 18th Progress resupply ship launched to the International Space Station is guided to docking with the Zvezda service module's aft port via manual control from commander Sergei Krikalev. A problem thwarted plans for an automated linkup.

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Shuttle collection
As excitement builds for the first space shuttle launch in over two years, this comprehensive video selection captures the major pre-flight events for Discovery and her seven astronauts.
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House hearing on ISS
The House Science Committee, Subcommittee on Space and Aeronautics, begins its hearing on the International Space Station. (29min 59sec file)
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Phillips testifies
House members question Expedition 11 crew member John Phillips living on the International Space Station. (16min 33sec file)
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Past ISS astronauts
The hearing continues with questioning by House members of former station astronauts Peggy Whitson and Mike Fincke. (31min 33sec file)
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Station update
A status report on the Expedition 11 crew's mission aboard the International Space Station is given during this news conference Monday. (55min 54sec file)

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Tropical Storm Arlene
A camera on the International Space Station captured this view of Tropical Storm Arlene moving into the Gulf of Mexico as the orbiting complex flew above the weather system at 2:33 p.m. EDT on Friday, June 10. (3min 06sec file)
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Whirling atoms dance into physics textbooks
Posted: June 24, 2005

NASA-funded researchers at the Massachusetts Institute of Technology, Cambridge, Mass., have created a new form of superfluid matter. This research may lead to improved superconducting materials, useful for energy-efficient electricity transport and better medical diagnostic tools.

This image shows a rotating superfluid made up of fermionic atoms. Credit: Andre Schirotzek, MIT
The research marks the first time scientists have positively created a friction-free superfluid using a gas of fermionic atoms, atoms with an odd number of electrons, protons and neutrons. The breakthrough happened on the night of April 13.

"It's a night I won't forget. It was overwhelming to watch on our computers as the lithium atoms behaved in a way that no one had ever seen before," said Dr. Wolfgang Ketterle, a Nobel prize-winning physics professor at MIT who led the team of researchers.

To accomplish this experiment, Ketterle's team cooled a gas cloud of lithium atoms to nearly absolute zero (about minus 459 degrees Fahrenheit). They used an infrared laser beam to trap the gas, then a green laser to spin it.

A normal gas simply spins, but a superfluid can rotate only by forming quantum whirlpools. A rotating superfluid looks like Swiss cheese; the holes are the cores of the whirlpools. This is exactly what the MIT physicists observed that night.

In 1995, Ketterle and his team were among the first to create a Bose-Einstein condensate, composed of bosonic atoms that have an even number of electrons, neutrons and protons. In Bose-Einstein condensates, particles act as one big wave, a phenomenon predicted by Albert Einstein in 1925. That discovery earned Ketterle a shared Nobel Prize in Physics in 2001. Bose-Einstein condensates were later shown to be superfluids.

The new frontier became fermions. Fermions must pair up to have an even number of electrons, neutrons and protons, which allows them to form a Bose-Einstein condensate. Breakthroughs at MIT and several other institutions, including Duke University, Durham, North Carolina, produced Bose-Einstein condensation of fermion pairs loosely bound as molecules, but found no concrete evidence of superfluidity.

Over the past two years researchers have been looking for the "smoking gun" for fermionic superfluidity. Despite some hints and indirect evidence, it was not found until this research team's discovery.

Superconductivity is superfluidity for charged particles instead of atoms. High-temperature superconductivity is not fully understood, but the MIT observations open up opportunities to study the microscopic mechanisms behind this phenomenon.

"Pairing electrons in the same way as our fermionic atoms would result in room-temperature superconductors," Ketterle explained. "It is a long way to go, but room-temperature superconductors would find many real-world applications, from medical diagnostics to energy transport." Superfluid Fermi gas might also help scientists test ideas about other Fermi systems, like spinning neutron stars and the primordial soup of the early universe.

The MIT research was supported by the National Science Foundation, the Office of Naval Research, the Army Research Office, and NASA's Fundamental Physics in Exploration Systems Mission Directorate, in support of the Vision for Space Exploration. NASA's Jet Propulsion Laboratory, Pasadena, Calif., Pasadena, manages the Fundamental Physics program.

The research was published in the June 23 issue of Nature. Ketterle's co-authors include MIT grad students Andre Schirotzek, Christian Schunck, and Martin Zwierlein, and former grad student Jamil Abo-Shaeer. They are all members of the NSF-funded MIT-Harvard Center for Ultracold Atoms.