NASA Home Page JPL Home Page Caltech Home Page
NASA - Jet Propulstion Laboratory + View the NASA Portal  
JPL Home JPL - Earth JPL - Solar System JPL - Stars and Galaxies JPL - Technology
Shell image/ Home button Fundamental Physics in Space
Technical Details
Shell image / home button
The Story of our Search
Adventures in Science
Technical Details
Experiments
Gravitational Relativistic Physics (GRP)
LCAP
LTCMP
BP
Library
News
Low Temperature and Condensed Matter Physics
    PRESENT: Ongoing Reseach
    FUTURE: BEST DYNAMX EXACT KISHT MISTE SUE SHE
    PAST: CHEX CVX LPE ZENO

Launch Date: October 1992
Mission Duration: During 9 day Space Shuttle Mission
Principle Investigator: Prof. John Lipa, Stanford University

 

Key Questions We Want to Answer:

The Lambda Point Experiment (LPE) flew aboard the Space Shuttle Columbia (STS-52) in 1992 with the U.S. Microgravity Payload (USMP-1) mission. LPE was a vanguard experiment, taking advantage of the Shuttle's microgravity environment to perform ultra-precise measurements at the superfluid transition of helium.

What We Already Know:

LPE provided the strictest tests to date of theories that apply to cooperative phase transitions. A cooperative phase transition occurs in a material when it passes from a disordered state to an ordered one. The lambda transition of liquid helium, where supercooled helium transforms from a normal fluid into a superfluid, is an example of a cooperative phase transition. The lambda name came from the shape of helium's specific heat curve near the transition point, which is similar to the Greek letter lambda.

What We Hope to Find Out:

The focus of the experiment was testing Kenneth G. Wilson's Renormalization Group Theory, for which Wilson was awarded the Nobel Prize. Renormalization Group Theory postulates the nature of phase transitions, which are common occurrences in nature. A phase transition is as familiar as ice melting, as the water makes the change from a solid state into a liquid state.

How We'll Conduct Our Experiment:

LPE helped to build a wealth of data with wide-ranging implications for the examination of theories of phase transition behaviors. LPE pioneered technologies to make instruments and experiments capable of delivering precise measurements at the low temperatures of the lambda transition. Since this was the first major experiment of this type, it has provided many kinds of information that later experiments can utilize.

The LPE instrument consisted of ultra-precise thermometers and a test apparatus whose temperature could be held very stable. The high-resolution thermometers functioned in conjunction with a superconducting quantum interference device, nicknamed SQUID. The experiment was performed by pulsing heat into the well-isolated liquid helium sample and measuring the change of temperature caused by the heat pulse. By operating very close to the phase transition, the way that the helium's specific heat changes as the transition is neared can be deduced. Additional information:

Additional information:



Last Updated:

link to First Gov NASA logo