This week, Virgin Galactic rolled out WhiteKnightTwo, an aircraft designed to help launch space tourists if not humanity into a new age of space travel. WhiteKnightTwo will eventually carry SpaceShipTwo, a six-passenger rocketplane, nestled between its twin fuselages. Upon reaching an altitude of about 50,000 feet, WhiteKnightTwo will release its payload and SpaceShipTwo will rocket in an arcing plume into the dark void of space. The first flights are expected in late 2009 or 2010. Should you pack your bags for a new era in human history?
The vision and largesse of Paul Allen funded the progenitors of the Virgin Galactic fleet, WhiteKnightOne and SpaceShipOne. SpaceShipOne earned the Ansari X Prize in 2004 for being the first privately funded spacecraft to carry humans into space twice in two weeks. Already there was a vision of "space tourism," flights for the more budget-minded at just $200,000, in contrast to the estimated $25 million that Microsoft billionaire Charles Simonyi, to name one rich tourist, paid to fly a Russian Soyuz rocket to the International Space Station. But the grand vision encompasses far more than joy rides for the mass affluent. Space tourism hitches the wagon of rocket science to the star of market forces. In computing, technological advances have increased computing power while reducing cost in a steady, self-reinforcing cycle, a phenomenon known as "Moore's Law." The question is whether the dynamic behind cheap laptops might eventuate in full-blown, interplanetary space travel.Can't get there from here
The answer is: not likely. SpaceShipTwo actually will only barely scrape space, eking out a scant 68 vertical miles before succumbing to the gravitational dominance of Earth. The craft musters only about 1/16 the energy needed to reach even low orbit 100 miles up. The space station, reposing 200 miles from the earth's surface, is completely beyond reach.
Attaining such distances requires enormous energy; thus rockets are very tall and almost all fuel. We are accustomed to thinking that technology advances across a very broad front, often in a revolutionary fashion. For propulsion, however, there has been no next technology. With the V2, Nazi Germany built the first chemical rocket. Although subsequent engines have employed different designs and used different fuels, an exhaustive search for a clever, inexpensive way to escape the planet has come up empty.
Multitudes of chemical permutations have been tried, but even the most potent combination, fluorine and lithium, isn't radically better than the more venerable liquid oxygen and kerosene. Rockets powered by nuclear explosions were once envisioned. Splitting atoms can produce about 10 million times more usable energy than chemical combustion for a given amount of fuel. But even setting aside very significant engineering and environmental obstacles, nuclear bombs are not price competitive with kerosene. A matter-antimatter engine, if one could be built, would be more efficient than even nuclear fission, but only a few nanograms of antimatter have ever been produced, culled from tons of sub-atomic debris in very expensive, miles-long particle accelerators that consume gargantuan amounts of power.
The cost for putting a pound of anything in space essentially hasn't changed since the 1960s. In many respects, the space program is in retrograde motion, using technology broadly similar to that of four decades ago and pursuing goals already attained, such as NASA's plan to return the moon in 2018. Even the recent exploits of SpaceShipOne just recapitulate those of the Air Force X-15 project, which also dates to that golden age of space, the 1960s. Tang, anyone?Boys and their toys
Science fiction-reading software geeks seem particularly susceptible to the siren song of interplanetary travel. There is Allen, the Microsoft co-founder who has also funded the Allen Telescope Array, which cocks an ear for communications from extraterrestrial intelligence. PayPal cofounder Elon Musk has invested a huge part of his fortune searching for a "Moore's Law of space." In rockets, however, that approach produced failure, either pyrotechnical explosion or a sputtering launch short of the target orbit. Musk's company has made reliability their new top priority — and raised prices.
Amazon founder and CEO Jeff Bezos bought 165,000 acres (roughly three times the size of Seattle) in Texas to serve as a spaceport for his Blue Origin project. They are working on "New Shepard," an entrant in the space tourism business which will take off and land vertically. New Shepard is a step toward Bezos' proclaimed goal of an "enduring human presence in space." Google has established a $30 million prize which awaits the privately funded team able to send a robot to the moon. Meanwhile, in 2011 Google co-founder Sergey Brin will board the Soyuz — redoubtable work horse for more than 40 years — to check out space at first hand.
A notable outlier in this pattern is Bill Gates, whose views on space are much more reserved and circumspect. Consequently, when the first Space Shuttle launched in 1981, Paul Allen joined the throngs watching at Kennedy Space Center; Gates remained at work. In 1997, Gates praised the Mars Pathfinder mission as "a fine example of small science ... undertaken on a strict budget [with] limited, achievable goals." He believed space would not be transformative: "Though humanity will do some great things in space in the next 100 years, and there will be enormous benefits, I don't think what goes on in space will fundamentally change the way we live." For Gates, there's not going to be faster-than-light travel, so "as a species we're stuck in this part of the galaxy."Of philanthropy and misanthropy
Gates begins from the same basic premises about the pace and impact of scientific and technological change as Allen and the other would-be spacefarers. Likewise, all of them firmly believe in their ability to radically reshape the very definition of what is possible. Personal bias, however, leads them to different conclusions and actions. The space evangelists seek to transcend the present and this earth in an almost religious fashion. According to their creed, humankind will overcome its imperfections in the heavens, rising above mere terrestrial concerns in themselves paltry and base. Philosophically, the Bill and Melinda Gates Foundation stands in diametric opposition to rocket building. The Gateses seek to make heaven on Earth, directing science, technology, and the market toward more immediate service to humanity, particularly the most wretched of the earth.
If we can put a man on the moon ...