In recent months, several lines of scientific investigation converged and the result seems to be that humankind has gained the ability to prospect for water on other worlds. Most significantly, the LCROSS lunar impactor shot straight into a crater at 1.5 miles per second. It was literally a bombshell, but its impact on history will be no less great—the colossal smash sent giant chunks of ice from our moon flying into space.

A few weeks before, an analysis of the light bouncing off the moon had indicated that lunar dirt contains trace amounts of water all across its surface. Extracting this water would be more difficult than mining the plentiful ice in the craters, but it could be done.

By the beginning of this year, the Phoenix Mars Lander had already detected—in fact, stepped on—ice near the Martian south pole. But now a camera orbiting Mars has snapped pictures of 99% pure ice near the equator, which has an environment far more hospitable to humans and our technology than the poles do.

If this year’s discovery of additional evidence that Mars was once covered in oceans had been discovered a short while ago, it would again have been interpreted by the green movement as an ominous warning of what was in store for Earth. Instead, in the context of this year’s water discoveries, Mars has become a friendlier place. We now know that we could survive there using today’s technology, if it were important enough to do so.

In the media, and our culture generally, a dearth of imagination has prevented the long-term implications of all this from being noticed, and it’s terribly disheartening to see. The water discoveries should have been celebrated, if not with fanfare, at least with rapturous conversation around every dinner table in the world. “Have you heard? If a global catastrophe makes Earth uninhabitable, there’s a place we can go!” But unless you follow space news, you probably weren’t even aware that these discoveries had fundamentally changed the calculus of our society’s future and even the destiny of our species.

Lunar ice means that large scale colonization of the moon is now possible decades earlier than it would have been had the moon been barren. That saved time could make all the difference in a pinch. Imagine that a few decades after a robust lunar colony is established, an asteroid, epidemic, or nuclear war ravages our home planet. We will have lunar water (and the fact that we knew about it) to thank for the preservation of human culture and knowledge.

Importantly, this increased access to the moon has put it within reach of privately funded excursions. It is now likely that individual and corporate homesteaders could establish and defend lunar property rights before governments mobilize to prevent them, promoting the cause of liberty and spreading Karl Popper’s Open Society into the cosmos.

The transition from an Earth-bound civilization to a space-faring one will start with the moon, making Mars colonization an incremental step rather than a giant leap. Relatively soon after a lunar colony is established, the skills and technologies developed to extract lunar water for drinking, breathing, and fuel-making will be further developed to do the same tasks on Mars. People will become experienced with the four-day journey between Earth and the moon, which will greatly simplify the logistics of moving personnel and cargo to the Red Planet.

Another important discovery was made in 2009 that made Mars more accessible: it became half as far away. Ion engines have already proved themselves on deep space probe missions, but this year a redesigned engine called VASIMIR was announced that greatly extends the thrust and efficiency of ion drives. With these new engines, set to be tested in 2010 aboard the International Space Station, Mars could conceivably be reached in only 39 days—almost exactly half the time it took Columbus to reach the New World.

Stephen Hawking is right when he says that if we don’t colonize other worlds in the near future our species will become extinct sooner rather than later. This year’s discoveries of water on the moon and Mars is a profound gift—one that might extend the longevity of the human species by an order of magnitude. Despite all the headaches and misadventures this year, 2009 may not have been a washout after all.

“You’d swear you could touch the terrain,” HiRISE operations manager Eric Eliason said.

Alas.