For more than a decade, University of Minnesota researcher Bruce Hammer believed a magnetic levitation system that he developed could perfectly simulate the weightless environment of space and its impact on human cells and bones.

Trouble is, he couldn't be certain until someone rocket-fired a few cells into space for comparison.

The long wait ended Monday, when cells cultured and frozen at the U were sent to the International Space Station on the latest SpaceX flight.

Later this year, scientists on the station will thaw and observe the cells. The accelerated loss of bone mass in space has already been established — Hammer said astronauts lose bone at a rate of 1 percent to 3 percent per month in space, while an earthbound elderly person with osteoporosis would lose that much in a year.

But if these experimental cells change in the same way and at the same rate as the cells in the U's magnetic system, it will be a proof of concept that the system is an effective simulation.

"If we can demonstrate that magnetic levitation mimics microgravity, then we have a tool to do space biology on earth," said Hammer, talking shortly after Monday's launch at the Kennedy Space Center in Florida.

That in turn could accelerate the pace of research into the genetic and biological causes of osteoporosis, a disease of bone loss that afflicts 10 million Americans. Getting any one experiment to the space station can take years if not decades, whereas there would be no such time restrictions with the magnetic system at the U.

"It might accelerate the development of drug therapies that could influence the formation of new bone," said Louis Kidder, part of Hammer's research team who also observed the launch.

Just getting the cells to space was a task in and of itself. They needed to be frozen to an inactive state during the launch and flight to the space station; otherwise the heavy gravitational forces and vibrations of the spaceflight could affect them and taint the comparative research results.

But the rapid hot water thawing process that works on earth couldn't be done in the same way in space, where there are no open water taps because the water would then escape and float around the station. So they developed a closed system for thawing the cells.

Scientists on the station have a manual for how to conduct the experiment, but Hammer and Kidder said they are eager to interact with them over the next year and prove the validity of their magnetic system and its ability to expedite research.

"This gives us the opportunity to see what genes are being affected and what proteins are being affected and what metabolites are being affected," Hammer said, "and we can do it in a much quicker time."

Jeremy Olson • 612-673-7744