Space Station Experiment Reaches Ultracold Milestone

The International Space Station is formally dwelling to the good experiment in house: NASA’s Cold Atom Laboratory is now producing clouds of ultracold atoms.

The International Space Station is formally dwelling to the good experiment in house.

NASA’s Cold Atom Laboratory (CAL) was put in within the station’s U.S. science lab in late May and is now producing clouds of ultracold atoms often called Bose-Einstein condensates. These “BECs” attain temperatures simply above absolute zero, the purpose at which atoms ought to theoretically cease shifting fully. This is the primary time BECs have ever been produced in orbit.

CAL is a multiuser facility devoted to the examine of basic legal guidelines of nature utilizing ultracold quantum gases in microgravity. Cold atoms are long-lived, exactly managed quantum particles that present a great platform for the examine of quantum phenomena and potential purposes of quantum applied sciences. This NASA facility is the primary of its type in house. It is designed to advance scientists’ skill to make precision measurements of gravity, probing long-standing issues in quantum physics (the examine of the universe on the very smallest scales), and exploring the wavelike nature of matter. 

“Having a BEC experiment operating on the space station is a dream come true,” stated Robert Thompson, CAL challenge scientist and a physicist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “It’s been a long, hard road to get here, but completely worth the struggle, because there’s so much we’re going to be able to do with this facility.”

CAL scientists confirmed final week that the power has produced BECs from atoms of rubidium, with temperatures as little as 100 nanoKelvin, or one ten-millionth of 1 Kelvin above absolute zero. (Absolute zero, or zero Kelvin, is the same as minu 459 levels Fahrenheit, or minus 273 levels Celsius). That’s colder than the typical temperature of house, which is about 3 Kelvin (minus 454 levels Fahrenheit/minus 270 levels Celsius). But the CAL scientists have their sights set even decrease, and anticipate to achieve temperatures colder than what any BEC experiments have achieved on Earth.

At these ultracold temperatures, the atoms in a BEC start to behave not like the rest on Earth. In reality, BECs are characterised as a fifth state of matter, distinct from gases, liquids, solids and plasma. In a BEC, atoms act extra like waves than particles. The wave nature of atoms is often solely observable at microscopic scales, however BECs make this phenomenon macroscopic, and thus a lot simpler to review. The ultracold atoms all assume their lowest vitality state, and tackle the identical wave id, turning into indistinguishable from each other. Together, the atom clouds are like a single “super atom,” as a substitute of particular person atoms.

“CAL is an extremely complicated instrument,” stated Robert Shotwell, chief engineer of JPL‘s astronomy and physics directorate, who has overseen the challenging project since February 2017. “Typically, BEC experiments involve enough equipment to fill a room and require near-constant monitoring by scientists, whereas CAL is about the size of a small refrigerator and can be operated remotely from Earth. It was a struggle and required significant effort to overcome all the hurdles necessary to produce the sophisticated facility that’s working on the house station at this time.”

The first laboratory BECs have been produced in 1995, however the phenomenon was first predicted 71 years earlier by physicists Satyendra Nath Bose and Albert Einstein. Eric Cornell, Carl Wieman and Wolfgang Ketterle shared the 2001 Nobel Prize in Physics for being the primary to create and characterize BECs within the lab. Five science teams, together with teams led by Cornell and Ketterle, will conduct experiments with CAL throughout its first 12 months. Hundreds of BEC experiments have been operated on Earth because the mid-Nineteen Nineties, and some BEC experiments have even made temporary journeys to house aboard sounding rockets. But CAL is the primary facility of its type on the house station, the place scientists can conduct day by day research of BECs over lengthy intervals.

BECs are created in atom traps, or frictionless containers made out of magnetic fields or targeted lasers. On Earth, when these traps are shut off, gravity pulls on the ultracold atoms they usually can solely be studied for fractions of a second. The persistent microgravity of the house station permits scientists to look at particular person BECs for 5 to 10 seconds at a time, with the power to repeat these measurements for as much as six hours per day. As the atom cloud decompresses contained in the atom entice, its temperature naturally drops, and the longer the cloud stays within the entice, the colder it will get. This pure phenomenon ({that a} drop in stress additionally means a drop in temperature) can be the rationale {that a} can of spray paint will get chilly when the paint is sprayed out: the can’s inside stress is dropping. In microgravity, the BECs can decompress to colder temperatures than any earthbound instrument. Day-to-day operations of CAL require no intervention from the astronauts aboard the station.

In addition to the BECs comprised of rubidium atoms, the CAL group is working towards making BECs utilizing two totally different isotopes of potassium atoms.

CAL is at present in a commissioning section, through which the operations group conducts an extended sequence of checks to completely perceive how the CAL facility operates in microgravity.

“There is a globe-spanning team of scientists ready and excited to use this facility,” stated Kamal Oudrhiri, JPL’s mission supervisor for CAL. “The diverse range of experiments they plan to perform means there are many techniques for manipulating and cooling the atoms that we need to adapt for microgravity, before we turn the instrument over to the principal investigators to begin science operations.” The science section is anticipated to start in early September and can final three years.

The Cold Atom Laboratory launched to the house station on May 21, 2018, aboard a Northrop Grumman (previously Orbital ATK) Cygnus spacecraft from NASA’s Wallops Flight Facility in Virginia. Designed and constructed at JPL, CAL is sponsored by the International Space Station Program at NASA’s Johnson Space Center in Houston, and the Space Life and Physical Sciences Research and Applications (SLPSRA) Division of NASA’s Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington.

For extra details about the Cold Atom Lab, go to:

Calla Cofield​
818-393-1821
Jet Propulsion Laboratory, Pasadena, Calif.
calla.e.cofield@jpl.nasa.gov

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