Saying you're going to Mars is one thing. Getting there and paying for it is another thing altogether.
President Bush, who has spoken before in favor of returning to the moon and going on to Mars, got specific in Texas on Friday and set the deadline for 2019. That coincides with NASA planning that has revolved around setting up a base on the moon in 2004-2010, and on Mars 2016-2020.Last year, after the president made a moon-Mars proposal, the space agency put the price tag at $450 billion to $500 billion for going to the moon and establishing operations there, then sending an expedition to Mars.
The $15.2 billion NASA budget that Bush proposed for the next fiscal year includes nearly $1 billion for exploration - $188 million of it for technology and definition studies for an advanced launch system, a probe called Lunar Observer and a satellite called "Lifesat" which studies radiation biology problems.
Coincidental with the president's speech in Kingsville, Texas, the congressional Office of Technology Assessment issued a report that said transportation needs for Bush's "human exploration initiative" would be substantial.
If the United States wants a permanent lunar base, missions to Mars or a space-based defense system, the report said, it should be prepared to spend $10 billion to $20 billion in development costs alone for new launch systems.
"Because the nation cannot afford to invest in all the good ideas proposed for improved or new launch systems, Congress and the administration will have to choose from a wide range of options," the report said. "Some choices must be made in the next two to three years. Others can wait longer."
For the lunar outpost, NASA estimates it would need a launch vehicle capable of lifting 132,000 pounds - a payload 24.7 feet in diameter and 89 feet long.
For Mars, the rocket would have to carry a 308,000 pound payload. That compares with the 52,000 pound limit of the space shuttle. Even the Soviets' Energia booster, the largest in existence, can lift only 220,000 pounds to low Earth orbit.
"This large heavy lift vehicle is about 50 percent larger than any vehicle yet proposed for the Advanced Launch System program and about twice as large as the largest Shuttle-C NASA has contemplated," said OTA. "Building such a vehicle would require a new development effort, including development of high-thrust liquid engines."
Advanced Launch System studies had been paid for by the Air Force, which decided not to pursue them. NASA also is thinking, but has not begun development, of Shuttle-C, in which the astronaut-carrying orbiter would be replaced by a giant cargo canister. Developing Shuttle C is estimated to cost $1.1 billion and each launch would be $400 million, according to the study.
The report also said:
- Congress should decide whether to develop a rescue vehicle for astronauts aboard the space station that will be in orbit late in the decade. It would cost $1 billion to $2 billion.
- Congress should look to developing two new launch systems: a personnel carrier-launch system that would carry little cargo and be launched atop an expendable rocket, and a larger advanced manned launch system using a reusable vehicle.