WASHINGTON — A $52 million physics experiment NASA plans to send to the international space station in 2016 is scheduled for a critical design review — the last milestone before hardware construction begins — in January.

“We just went through preliminary design, and we’re marching to critical design review in January of next year, a few months from now [with] launch in September 2016,” Mark Lee, fundamental physics science lead at NASA headquarters in Washington, told the National Research Council’s committee on biological and physical sciences in space Oct. 7.

The Cold Atom Lab is being built by NASA’s Jet Propulsion Laboratory in Pasadena, California, and will be carried to the ISS aboard a Space Exploration Technologies Corp. Dragon capsule. Once it is unpacked, astronauts will install the science payload inside one of the space station’s standardized Express experiment racks.

The Cold Atom Lab is designed to be operated remotely from Pasadena. The experiment, slated to run at least one and as many as five years, will take advantage of microgravity to cool atoms to temperatures impossible to reach in Earth gravity, Lee said.

“In space, you can have a very stable, stationary atom. With that, this atom is very cold. When an atom becomes very cold, it becomes a quantum system. It’s not a regular atom. By doing that in the microgravity, we really can probe very deep into the atom, and other fundamental physics,” Lee said.

Cold atom physics is the type of research for which former U.S. Secretary of Energy Steven Chu won a one-third share of the 1997 Nobel Prize in physics. NASA’s contribution to the field will be funded by the agency’s Human Exploration and Operations Mission Directorate, Lee told the NRC panel.

In January, NASA spread $12.7 million among seven Cold Atom Lab science investigations under the Research Opportunities in Fundamental Physics program, and the agency is already looking ahead toward building the next Cold Atom Lab.

However, the first discussions about Cold Atom Lab 2 will not begin until December 2015, Lee said, when NASA has notionally scheduled a science definition workshop for the follow-on physics project.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.