XCOR Aerospace

The latest design for XCOR Aerospace's Lynx rocket plane includes an optional pod that can hold experimental payloads.

Researchers have struck million-dollar deals for as many as 17 flights aboard two kinds of private-sector suborbital spaceships, with the prospect of many more in future years. "This is just whetting people’s taste for what is to come," said Alan Stern, a planetary scientist who helped engineer the deals and is due to be one of the first to fly.

Stern, an associate vice president at the Southwest Research Institute, is leading SwRI's suborbital research effort and is also presiding over this week's Next-Generation Suborbital Researchers Conference in Orlando, Fla. The conference is bringing together scientists and space entrepreneurs to develop what Stern calls a "killer app" for spaceflight: zero-G research in rocket-powered suborbital vehicles.

SwRI is involved in both of the deals announced over the past few days: One calls for two researchers to fly on Virgin Galactic's SpaceShipTwo rocket plane, with an option to purchase six more seats for a total value of $1.6 million. The other sets aside six flights on XCOR Aerospace's Lynx rocket plane, with an option for three more flights.

Virgin Galactic has begun glide tests of its first SpaceShipOne craft, dubbed the VSS Enterprise, and expects to start rocket-powered tests by early 2012. XCOR's chief operating officer, Andrew Nelson, said the first Lynx flight tests were slated for early 2012 as well.

"I expect there's a good chance that the first flights could be late next year," Stern told me today. "The majority would be in '13, two years from now."

If all 17 spots are purchased, "this program will put more launches of human beings into space" than any single government agency over the 2012-2014 time period, Stern pointed out. When you lump together all the government-backed astronauts and cosmonauts going to the International Space Station, the total may be bigger, but "if you count just the number of NASA astronauts in those three years, you will find that it's a smaller number," he said.

The cost for the Virgin flights averages out to the standard tourist rate of $200,000 per seat. Virgin Galactic says its SpaceShipTwo flights will reach almost 70 miles in altitude and provide several minutes of zero gravity.

Neither Stern nor Nelson would say how much SwRI would pay for the XCOR Lynx flights, but the tourist rate for the Lynx is $95,000 per seat. Nelson said the first Lynx model to enter service, the Mark I, would rise to at least 38 miles in altitude and yield just under a minute of zero-G — which is enough for SwRI's purposes. The Lynx production model, the Mark II, could fly about twice as high and provide longer stretches of microgravity.

Stern said he would be one of the researchers going into space as part of the deal. Two other SwRI staffers, Dan Durda and Cathy Olkin, have also been trained for spaceflight. SwRI will be paying for all the flights out of its research and development budget.

Three experiments are ready for flight, Stern said: One involves monitoring the researchers' vital signs during zero-G as well as their high-G ascent and descent. Researchers will also make astronomical observations out the windows of the rocket planes using an ultraviolet imager. Durda , meanwhile, has prepared a sample of simulated asteroid-type material that will be studied during the different phases of flight. Such research with fake asteroid stuff could help scientists figure out what to expect if a human mission is sent to land on a real asteroid, as the Obama administration has proposed.

Stern said the SwRI space program was aimed at priming the pump for scientific studies using piloted suborbital spacecraft. Such flights offer a low-cost, quick-turnaround alternative to research on the International Space Station, which generally involves a years-long procedure for approving and executing experments.

"Someone had to break the ice," Stern said. "We're very proud to be the first."

Other companies, including Armadillo Aerospace and Blue Origin, are also working on suborbital spaceships, and Stern said SwRI has been in discussions with those ventures as well for future flights.

"We're building a spaceflight program, and we'll take all comers" Stern said.

Other perspectives on suborbital science:

• Space.com: Virgin signs deal to launch scientists into space
• The Space Review: Suborbital back out of the shadows
• New York Times: One giant leap for researchers

Stern is due to discuss suborbital science initiatives on March 13 on "Virtually Speaking Science" with co-hosts Alan Boyle and Robin Snelson. Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto."