For Charles A. "Karl" Hibbitts and 11 other scientists who hope to fly into space with their experiments someday, the path out of the Earth's atmosphere starts in Philadelphia.
Hibbitts, a research scientist at the Johns Hopkins University's Applied Physics Lab near Laurel, and his fellow space cadets spent two days last week at a private space training center near Philly getting a taste of the rigors and risks of a quick shot, 350,000 feet up to the edge of space and back.
One passed out briefly in a hypobaric chamber that simulated aircraft depressurization at 18,000 feet. Hibbitts confessed to some nausea as he spun in a centrifuge that duplicated the six-fold pressure of gravity they'll experience while re-entering the Earth's atmosphere.
It "was like an elephant sitting on me," he wrote afterward in his blog. "It was tougher than I thought. ... If you have any health problems, no, you wouldn't qualify. But a normal, healthy person off the street truly would."
Brief, suborbital jaunts into space aboard small, commercial rocket-planes will - perhaps in the next year or two, the scientists say - become a realistic, affordable alternative for those who need to get their experiments above the Earth's atmosphere.
"It's not an ideal platform; we will have to learn how to use these vehicles," Hibbitts said. "But ... it does get us to the edge of space, and ... $200,000 is inexpensive compared to a sounding [unmanned, suborbital] rocket or a balloon."
The $3,000 training session at the private National AeroSpace Training and Research Center was a first for space scientists. It was organized by Alan Stern, a planetary scientist and former NASA assistant administrator. He long advocated that NASA support human suborbital missions, without success.
Stern is now a consultant to airline magnate Richard Branson's Virgin Galactic. The company's two-stage SpaceShipTwo, with room for six passengers, is said to be the front-runner among vehicles under development by five private companies racing to open a commercial spaceflight market for tourists and scientists. Stern also heads a committee for the industry's Commercial Spaceflight Federation.
For scientists, Stern said, the new vehicles are "a breakthrough in terms of price point and the frequency of flights."
Where NASA flies perhaps 20 unmanned sounding rockets each year, he said, "these guys are going to be flying hundreds. That means we will have the ability to do things we've never done before. We can do an experiment one day, then change the conditions and do it again the next day."
Hibbitts, 42, is a geophysicist, a former U.S. Marine air traffic controller and artillery officer. His research at APL focuses on studying the composition and history of airless bodies in our solar systems, including Earth's moon, the asteroids, and certain moons of Jupiter and Saturn.
He especially wants to observe the moon in the infrared wavelengths he believes will reveal more information about the water that's been detected there. But to do that he needs to get his instruments above the water in the Earth's atmosphere.
NASA's suborbital rockets and balloons don't do planetary work. And space telescopes like the Hubble or Spitzer either lack the right instruments or are oversubscribed, Hibbitts said.
Manned suborbital flights would offer scientists only two to five minutes of observation time. "We will not have time to look out the window," he said. "It's over in a moment, and the scientist will be totally occupied."
But with a human along, "you can take an instrument that operates manually. You don't have to develop a rigorous, foolproof automated system," Hibbitts said. And it doesn't have to radio its data to Earth. "It's a huge cost savings."
One hitch is the risk to human life, however brief. But plenty seem willing to trust the new technology.
In Hibbitts' inaugural class this week, there were would-be suborbital astronauts from APL, Boston University, the Denver Museum of Natural Sciences, the Massachusetts Institute of Technology, the University of Central Florida and the University Space Research Association.
The first day included classroom training in the physiology of high-altitude flight. That was followed by a hypobaric chamber "ride" to 18,000 feet, to show scientists how to respond to sudden depressurization of their spacecraft.
"Mostly it gives you a visceral understanding of what it's like to be hypoxic. You're tingly and not thinking very clearly, and not realizing you're not thinking very clearly," he said. "One person actually passed out."
Hypoxia "can be very serious. We got a true understanding of how little time you have to recover and put on an oxygen mask."
The second day included two sessions aboard the spinning capsule of the centrifuge. One exposed them to four 30-second runs at two to three "Gs" - two to three times the force of gravity - directed from the head down through the body. "It's quite a kick in the seat of your pants. It feels like we're really launching," Hibbitts said.
The G forces drive blood from the brain, so the students had to learn to strain their legs and bodies to squeeze the blood, and oxygen, back to their craniums. "It's fatiguing," Hibbitts said. "The main thing is my legs are tired. "
The second session drove up to six Gs against the students' chests, simulating the deceleration of re-entry into the Earth's atmosphere.
Because the centrifuge is spinning around a central axis, it doesn't exactly duplicate the real sensations of flight. Turn your head to look around as Hibbitts did, and you can get dizzy and nauseous.
Stern compares this first venture into manned suborbital science to the introduction of personal computers in the 1970s. "The real applications are probably ones we haven't thought of yet," he said. But he offered a few guesses.
"In 10 years, grad students will be doing experiments on suborbital vehicles," he said. "In 20 years, Boy Scout merit badges may include spaceflight. The future is coming."