Space Initiative Puts Researchers in a Spin

In early experiments with human centrifuges, researchers used the devices to try to cure emotionally troubled patients.

The technique didn’t catch on.

But centrifuge technology has since advanced to help pilots and astronauts prepare for missions. The technology could serve other purposes.

Sometime in this century — possibly in the coming decades — human centrifuges may help fulfill some of humanity’s most ambitious dreams of space exploration.

El Segundo-based Wyle Laboratories has spent the past two years developing a human centrifuge for study of the effects of artificial gravity on humans. The research ultimately could make human space missions safer and longer.

Wyle Laboratories is developing the centrifuge for NASA, which is searching for ways to limit damage to astronauts’ health in space.

NASA has held periodic workshops on artificial gravity since the late 1950s, said Bill Paloski, who heads NASA’s human adaptation and countermeasures office at Johnson Space Center in Houston. Paloski said the space agency’s attention to artificial gravity intensified after President Bush announced in January an initiative to send robots and humans to the moon, Mars and beyond.

“The president’s announcement sort of accelerated it,” Paloski said. “Instead of having a nondescript plan or some sort of plan in the future, we have a specific plan in the near future.”

A centrifuge is an apparatus that rotates at a high speed creating enough force to separate chemical substances inside or — in the case of human centrifuges — simulate the conditions of accelerated flight. For example, a washing machine on spin cycle is a type of centrifuge.

In theory, a centrifuge could create artificial gravity to help compensate for the tiny amount of gravity in space known as microgravity. During long human space missions, an astronaut may be able to lie in a spinning centrifuge for a specified length of time each day to help return one’s body to equilibrium.

The need for gravity in space is far more important than simply an issue of astronaut comfort. Long-term exposure to microgravity causes loss of muscle mass and bone density, and weakens the immune system.

Without the addition of artificial gravity, astronauts’ health could deteriorate over time enough to limit their ability to conduct experiments or perform other tasks.

“The Apollo missions were 10 to 11 days. The Mars mission could be two to three years,” said Larry Meeker, Wyle Laboratories’ director of special projects.

Because Earth and Mars follow different paths around the sun, the launch window between the two planets comes only every two years. The window lasts about a week to 10 days. A one-way trip takes about six months.

In addition, once astronauts arrive on Mars, the red planet would provide only a little more than a third of Earth’s gravity.

Yet, there’s no consensus on whether manned missions to Mars would require artificial gravity since NASA already uses “countermeasures” such as exercise and medication that at least partially reduces the harmful effects on bone and muscle tissue, Paloski said.

“The question of whether we should provide gravity on a Mars trip has been there for a long time,” Paloski said. “There’s not a consensus. There’s a community that believes, yes, we need it. There’s a community that says we don’t need it.”

There is consensus, however, that human missions beyond Mars would require artificial gravity, Paloski said.

While each ailment from lack of gravity may have a specific treatment, artificial gravity “has the potential to offset the effects of multiple symptoms at one time,” Paloski said.

In August, Wyle Laboratories shipped its centrifuge to the University of Texas, at Galveston, where NASA will use it in experiments.

The El Segundo-based company is leveraging its expertise in building equipment centrifuges, which test the durability of components before they’re sent into space. The company built a human centrifuge last year for pilot flight tests in Sweden.

Wyle Laboratories also provides millions of dollars a year in medical support and other flight services for NASA.

“This is the beginning of a big deal because it combines the different talents we have in the different divisions,” Wyle Laboratories chairman, president and CEO Gus Yiakas said of the experimental centrifuge.

If NASA determines that the centrifuge tests are positive, researchers in Germany and Russia would each acquire a test model to help conduct further experiments.

Other ideas for making human space travel more tenable include building a large spacecraft that would spin continuously, creating its own perpetual artificial gravity, like in the 1968 science fiction movie “2001: A Space Odyssey.”

“Then it becomes a passive countermeasure, and all day you’re exposed to that just like it is here on Earth,” Paloski said.

But such a spacecraft likely would add to the expense of travel. In addition, once on Mars or another planet or moon, astronauts would again be without enough gravity.

Another solution being considered involves using a more powerful propulsion system to cut a six-month trip to Mars to only one month, Paloski said.

“There are some folks at NASA and other places who are working on novel propulsion systems that would allow us to get there quicker,” Paloski said.

Meeker, a long-time engineer in the space industry, has spent years writing about the potential of artificial gravity. He came out of retirement last year to work on the Wyle Laboratories centrifuge.

Meeker says he’s surprised that humans haven’t traveled outside Earth’s orbit yet.

“I worked on the Gemini program and Apollo,” Meeker said. “If you’d have told me then that I’d be standing here in 2004 and we weren’t doing interplanetary missions, I wouldn’t have believed you.”