Ever since the last NASA space shuttle mission touched down in Florida on July 21, there has been a spirited debate in articles and blogs across the Internet over the future of humans in space.
Congress has directed NASA to build a super-rocket with the brawny power to hurtle astronauts out of Earth orbit and onto interplanetary destinations.
The largely vague justifications for “boldly going” there emphasize the uniquely American notion of conquering the frontier, “living in space,” and planetary colonization as our manifest destiny.
But I’d like to offer a goal that is more tangible and far overarching. On many different levels, space pioneers could focus on answering, arguably, the most profound question every asked by humans: are we alone in the universe?
The answer to this question is equally profound either way it falls. If we find life elsewhere in the solar system, then life is unequivocally a condition of the universe. Find life once it’s a miracle, twice, it’s a statistic.
Conversely, failure to find the humblest of microbes on other worlds implies that there is something extraordinarily unique about the evolution of Earth that allowed for the emergence of self-replicating matter.
Yes, we have robots exploring the planets for traces of life as we know it, telescopes inventorying planets circling other stars, and SETI astronomers listening for the whispers of an intelligent signal beamed in out direction from across the galaxy.
But human space exploration is ultimately needed to provide solid evidence for life among the planets and stars, writes Ian Crawford of Birkbeck College, the University of London. “Astronauts may be expected to make discoveries that would be overlooked by robots, owing to the uniquely human ability to recognize new observations,” he said.
This pursuit isn’t just about finding Martian bugs, it could yield insights to how life got started on Earth four billion years ago. The clues to matter’s transition from chemical reactions to biological reactions are largely erased on Earth, but they are likely kept in time capsules on the moon and Mars. Uncovering them requires the cunning, skill and perseverance of Indiana Jones searching for lost treasure.
Yes, launching an armada of robot geologists is vastly cheaper that the infrastructure, complexity and freight costs associated with sending humans elsewhere. But the robots’ experiments are one-shot, as in the case of the ambivalent 1970s Viking biology experiments on Mars. Whats more, in situ biology labs can be miniaturized only so far.
Major NASA endeavors like the Apollo moon landings and the repair of the Hubble Space Telescope dramatically demonstrated the agility and adaptability of humans as explorers and off-world problem solvers.
Here is a glimpse of what the next decades could offer if we focus our space resources on answering the ultimate question of a living universe:
An Antarctic-type science lab outpost on the moon hosts teams of astrogeologists to search for samples of Earth’s early atmosphere preserve deep beneath the lunar surface. The moon may also have collected meteorites blasted of the Earth that could contain 4-billon year old microbial fossils of some of the earliest life to appear on our planet. Teams extract ices at the polar caps to sample the first primitive organic material in the solar system.
Large quantities of rocks collected from diverse locations around the Red Planet are carried to a manned Mars base. Mars geologists and paleontologists conduct thorough analysis. The outpost contains a fully equipped lab facility. This largely sidesteps the risks of bringing limited rock samples back to Earth intact for detailed analysis. Heavy duty drilling equipment is erected and operated by astronauts. The machinery digs deep into the Marian past, many hundreds of feet into bedrock to extract core samples covering billions of years of evolution.
Immense space telescopes, with segmented mirror arrays making them hundreds of times more powerful than Hubble, chemically sample the atmospheres of the nearest Earth-like planets at neighboring stars. This allows astronomers to assemble a catalog of inhabited worlds. To justify the investment, these space facilities are cared for like their ground-based telescopic cousins. They are routinely repaired and upgraded by astronaut crews. These international space assets operate for decades.
Far into the next century, scientists develop machines to survey the nearest exoplanets that have been identified as inhabited, and are old enough for the emergence of complex life. Only by having our robotic emissaries visit these worlds can humans witness the diversity of evolving creatures in an alien ecosystem. The irony here is that interstellar exploration will force us to build intelligent machines that will need to explore and make decisions purely on their own.
These starships will require a barely imagined scale of engineering and energy production. Such complex vehicles will have to be assembled in space by humans. Astronauts would not be passengers on the multi-generation missions, but the construction crews. Sorry Captain Kirk, the job’s all Scotty’s.
The costs of such bold long-term methodical program of searching for life is incalculable. But the scientific payoff is immeasurable.
“The problem is we don’t know what we are looking for, we don’t know what its made of, we don’t know where to look, but we’re still going to try,” says astrobiologist Andrew Steele of the Carnegie Institution. “If life doesn’t jump off the microscope slide and shake your hand, you’re going to need more than one observation. There’s no Nobel Prize here. Finding extraterrestrial life is going to take a long series of observations and tests.”
Image credits: Getty (top), NASA