If only there were gas pumps on Mars.
That is the wishful thinking NASA is doing now as it contemplates sending humans to the Red Planet, as directed by President Bush.
NASA is considering proposals submitted last month from a handful of companies for a spacecraft propulsion system that could refuel on Mars and other planets. Some of the companies that submitted bids include Alliant Techsystems Inc. and Northrop Grumman Corp., which both employ hundreds of people in Maryland.
The designs center on an engine fueled by a mix of liquid oxygen and liquid methane, the components of which are found naturally on Mars. The propellants, which NASA dubs "LOX/methane," are nontoxic and safer than those that power the space shuttle. And astronauts would not have to carry heavy fuel for the return trip but could fill up at an outpost in deep space.
"If we go to Mars at some point, it will be a method of living off the land," said Mark D. Klem, project manager for NASA's Propulsion and Cryogenic Advanced Development project, which seeks out technologies that could be developed for future NASA missions.
"It's far off," he said, noting that NASA does not have a timetable for a potential Mars mission. "But like anything, you have to start small."
While NASA has given some of the companies contracts valued at $7 million to $10 million each for development, the businesses are making their own investments.
Alliant Techsystems, which is better known by its ticker symbol ATK, has committed money and employees to the development of such an engine with partner XCOR Aerospace.
Last year, the company successfully test fired a 7,500-pound thrust LOX/methane engine in the Mojave Desert to demonstrate that the technology works.
John "Jack" Cronin, president of ATK's Mission Systems division, based in Canton, believes a LOX/methane engine is "in lock-step with NASA's future."
The company has been working on the technology for a decade, and it will be an important program as ATK shifts more of its focus to space, Cronin said.
ATK recently made two significant acquisitions - Swales Aerospace of Beltsville and the space and radar business of Canada's largest space company, MDA - and aspires to be one of the nation's largest space companies.
"I think [the LOX/methane engine is] critical for both us and NASA," he said.
It is not unusual for big companies to spend their money on research in hopes that it will ultimately yield a lucrative long-term contract, said analyst Marco A. Caceres, senior space analyst with the Teal Group Corp. in Fairfax, Va.
Because the engines are not reusable, he said, NASA would have to order new ones for every mission, providing a steady stream of revenue for the winning manufacturer.
"Most of these companies are looking far into the future," Caceres said. "They believe NASA's vision for Mars exploration will continue well into the next generation."
More immediately, NASA said it would consider the methane technology among others for the Lunar Lander. The Lander will be attached to the next-generation space shuttle, Orion, and ferry astronauts to and from the moon.
Methane or its components are not present on the moon, so the Lander would have to be equipped with its own reserve of LOX/methane. Klem said NASA is considering it anyway for the Lander as a way to test the technology before launching a mission to Mars.
If NASA pursues LOX/methane for the Lander, it likely will solicit bids from ATK and the other companies that submitted last month's proposals.
Though the idea of using "green" propellants has been around a while - the V-2 rockets favored by the Nazis were powered by liquid oxygen and ethanol - the companies acknowledge that the technology is still nascent.
Most NASA rockets, including those found on the space shuttle, are powered by a mix of fuel that includes liquid hydrogen, which must be stored at minus 252.9 degrees Celsius. But liquid methane can be stored at warmer temperatures - a balmier minus 161.6 degrees Celsius - and would not need as much insulation, which would make the vehicle lighter and cheaper to launch, according to NASA.
To produce methane on Mars, astronauts would need to mix carbon dioxide with hydrogen and heat it. Klem said astronauts could gather hydrogen on the red planet by melting Martian ice, and get carbon dioxide from the atmosphere.
Methane is more plentiful on Saturn's moon, Titan. It also is found on Jupiter, Saturn, Uranus, Neptune and Pluto, which could expand space exploration to deep space, Klem said.
The challenge for NASA and the companies designing a LOX/methane engine is how to safely ignite methane in a sub-freezing climate. Unlike other fuel sources that combust when mixed together, methane must be ignited to burn with oxygen.
Aerojet, which submitted a competing bid to NASA, first started working on LOX/methane technology in the 1960s. (Engines made by Aerojet's predecessor were used in the Apollo mission.) But the Sacramento, Calif., company looked at it more seriously two years ago when NASA was considering the technology for Orion's engines traveling back from the moon. That idea was scrapped when the time frame for building Orion was accelerated.
"It takes more energy to go to the moon than the Space Station," said R. Joseph Cassady, director of business development at Aerojet. "So in order to go to Mars, we're going to need better gas mileage."
Northrop Grumman's Space Technology Sector has two contracts with NASA for related technology using "green" propellants. It also submitted a proposal for the LOX/methane engine. The Los Angeles-based company's legacy, which employs more than 10,000 in Maryland, also dates to the Apollo era, and it would relish the chance to send astronauts back to the moon or to Mars.
"This is the initial ticket to the game," said Don Miller, director of advanced space technologies for the sector.
If ATK were successful in getting a NASA contract to develop the engine, some of the work likely would be done in Maryland, where ATK plans to establish the headquarters for its newest division, ATK Space. The company employs more than 2,000 in Maryland.
But regardless of who wins the engine contract, analyst Caceres said the research money the companies have spent on LOX/methane may not be wasted. Like many NASA technologies, from Velcro to the microwave, the work may well spin off technologies that could be used on Earth.
For example, ATK, Aerojet and Northrop Grumman also plan on submitting proposals for a LOX/methane engine to the Air Force, which is exploring new and cheaper propulsion technologies for launching satellites.
"It takes a lot of money to get something off the ground and into space," said Cassady, of Aerojet.