Space Chronicles: Facing the Ultimate Frontier (19 page)

D
isposal of dead weight was a key to their success. If you want to reach orbital speeds—just over seventeen thousand miles an hour—you’d better unladen your rocket at every opportunity. Rocket motors are heavy, fuel tanks are heavy, fuel itself is heavy, and every kilogram of unnecessary mass schlepped into space wastes thousands of kilograms of fuel. The solution? The multistage rocket. When the first-stage fuel tank is spent, throw it away. Run out of fuel in the next stage; throw that away too.

Jupiter-C, the rocket that launched Explorer 1, weighed 64,000 pounds at takeoff, fully loaded. The final stage weighed 80.

Like the R-7 rocket that launched Sputnik 1, the Jupiter-C was a modified weapon. The science was a secondary, even tertiary, outgrowth of military R&D. Cold warriors wanted bigger and more lethal ballistic missiles, with nuclear warheads crammed into the nose cones.

High ground is the military’s best friend, and what ground could be higher than a satellite orbiting no more than forty-five minutes away from a possible target? Thanks to Sputnik 1 and its successors, the USSR held that high ground until 1969, when, courtesy of von Braun and colleagues, the USA’s Saturn V rocket took the Apollo 11 astronauts to the Moon.

Today, whether Americans know it or not, a new space race is under way. This time, America faces not only Russia but also China, the European Union, India, and more. Maybe this time the race will be one between fellow travelers rather than potential adversaries—more about fostering innovations in science and technology than about struggling to rule the high ground.

• • •
CHAPTER SIXTEEN

2001—FACT VS. FICTION
^*

T
he long-awaited year has come and gone. There was no escape from the relentless comparisons between the spacefaring future we saw in Stanley Kubrick’s
2001: A Space Odyssey
and the reality of our measly earthbound life in the real 2001. We don’t yet have a lunar base camp, and we have not yet sent hibernating astronauts to Jupiter in outsize spaceships, but we have nonetheless come a long way in our exploration of space.

Today, the greatest challenge to human exploration of space, apart from money and other political factors, is surviving biologically hostile environments. We need to send into space an improved version of ourselves—doppelgangers who can somehow withstand the extremes of temperature, the high-energy radiation, and the meager air supply, yet still conduct a full round of scientific experiments.

Fortunately, we have already invented such things: they’re space robots. They don’t look humanoid and we don’t refer to them as “who,” but they conduct all of our interplanetary exploration. You don’t have to feed them, they don’t need life support, and they won’t get upset if you don’t bring them home. Our ensemble of space robots includes probes that are monitoring the sun, orbiting Mars, intercepting a comet’s tail, orbiting an asteroid, orbiting Saturn, and heading to Jupiter and Pluto.

Four of our early space probes were launched with enough energy and with the right trajectory to escape the solar system altogether, each one carrying encoded information about humans for the intelligent aliens who might recover the hardware.

Even though humans have not left footprints on Mars or on Jupiter’s moon Europa, our space robots at these worlds have beamed back to us compelling evidence of the presence of water. These discoveries fire our imaginations with the prospect of finding life on future missions.

We also maintain hundreds of communication satellites, as well as a dozen space-based telescopes that see the universe in different bands of light, including infrared and gamma rays. In particular, the microwave band allows us to see the edge of the observable universe, where we find evidence of the Big Bang.

And so, we may have no interplanetary colonies or other unrealized dreamscapes, but our presence in space has been growing exponentially nonetheless. In some ways, space exploration in the real 2001 strongly resembles that of Kubrick’s movie. Apart from our flock of robotic probes, we have a fleet of hardware in the sky. Just as they do in
2001
the movie, we’ve got a space station. It was assembled with parts delivered by reusable, docking space shuttles (which happened to say “NASA” on the side instead of “Pan Am”). And, as in the movie, the space station has zero-G flush toilets, with complicated instructions, and plastic pouches of unappealing astronaut food.

As far as I can tell, the only things Kubrick’s movie has that we don’t have are Johann Strauss’s “Blue Danube” waltz filling the vacuum of space, and a homicidal mainframe named HAL.

• • •
CHAPTER SEVENTEEN

LAUNCHING THE RIGHT STUFF
^*

I
n 2003 the space shuttle orbiter Columbia broke into pieces over central Texas. A year later, President George W. Bush announced a long-term program of space exploration that would return humans to the Moon and thereafter send them to Mars and beyond. Over that time, and for years to come, the twin Mars Exploration Rovers, Spirit and Opportunity, wowed scientists and engineers at the rovers’ birthplace—NASA’s Jet Propulsion Laboratory (JPL)—with their skills as robotic field geologists.

The confluence of these and other events resurrects a perennial debate: with two failures out of 135 shuttle missions during the life of the manned space program, and its astronomical expense relative to robotic programs, can sending people into space be justified, or should robots do the job alone? Or, given society’s sociopolitical ailments, is space exploration something we simply cannot afford to pursue? As an astrophysicist, as an educator, and as a citizen, I’m compelled to speak my mind on these issues.

Modern societies have been sending robots into space since 1957, and people since 1961. Fact is, it’s vastly cheaper to send robots—in most cases, a fiftieth the cost of sending people. Robots don’t much care how hot or cold space gets; give them the right lubricants, and they’ll operate in a vast range of temperatures. They don’t need elaborate life-support systems either. Robots can spend long periods of time moving around and among the planets, more or less unfazed by ionizing radiation. They do not lose bone mass from prolonged exposure to weightlessness, because, of course, they are boneless. Nor do they have hygiene needs. You don’t even have to feed them. Best of all, once they’ve finished their jobs, they won’t complain if you don’t bring them home.

So if my only goal in space is to do science, and I’m thinking strictly in terms of the scientific return on my dollar, I can think of no justification for sending a person into space. I’d rather send the fifty robots.

But there’s a flip side to this argument. Unlike even the most talented modern robots, humans are endowed with the ability to make serendipitous discoveries that arise from a lifetime of experience. Until the day arrives when bioneurophysiological computer engineers can do a human-brain download on a robot, the most we can expect of the robot is to look for what it has already been programmed to find. A robot—which is, after all, a machine for embedding human expectations in hardware and software—cannot fully embrace revolutionary scientific discoveries. And those are the ones you don’t want to miss.

I
n the old days, people generally pictured robots as a hunk of hardware with a head, neck, torso, arms, and legs—and maybe some wheels to roll around on. They could be talked to and would talk back (sounding, of course, robotic). The standard robot looked more or less like a person. The fussbudget character C3PO, from the
Star Wars
movies, is a perfect example.

Even when a robot doesn’t look humanoid, its handlers might present it to the public as a quasi-living thing. Each of NASA’s twin Mars rovers, for instance, was described in JPL press packets as having “a body, brains, a ‘neck and head,’ eyes and other ‘senses,’ an arm, ‘legs,’ and antennas for ‘speaking’ and ‘listening.’ ” On February 5, 2004, according to the status reports, “Spirit woke up earlier than normal today . . . in order to prepare for its memory ‘surgery.’ ” On the 19th the rover remotely examined the rim and surrounding soil of a crater dubbed Bonneville, and “after all this work, Spirit took a break with a nap lasting slightly more than an hour.”

In spite of all this anthropomorphism, it’s pretty clear that a robot can have any shape at all: it’s simply an automated piece of machinery that accomplishes a task, either by repeating an action faster or more reliably than the average person can, or by performing an action that a person, relying solely on the five senses, would be unable to accomplish. Robots that paint cars on assembly lines don’t look much like people. The Mars rovers looked a bit like toy flatbed trucks, but they could grind a pit in the surface of a rock, mobilize a combination microscope-camera to examine the freshly exposed surface, and determine the rock’s chemical composition—just as a geologist might do in a laboratory on Earth.

It’s worth noting, by the way, that even a human geologist doesn’t go it alone. Unaided by some kind of equipment, a person cannot grind down the surface of a rock; that’s why a field geologist carries a hammer. To analyze a rock further, the geologist deploys another kind of apparatus, one that can determine its chemical composition. Therein lies a conundrum. Almost all the science likely to be done in an alien environment would be done by some piece of equipment. Field geologists on Mars would lug it around on their daily strolls across a Martian crater or outcrop, where they might take measurements of the soil, the rocks, the terrain, and the atmosphere. But if you can get a robot to haul and deploy all the same instruments, why send a field geologist to Mars at all?

O
ne good reason is the geologist’s common sense. Each Mars rover was designed to move for about ten seconds, then stop and assess its immediate surroundings for twenty seconds, then move for another ten seconds, and so on. If the rover moved any faster, or moved without stopping, it might stumble on a rock and tip over, becoming as helpless as a Galápagos tortoise on its back. In contrast, a human explorer would just stride ahead, because people are quite good at watching out for rocks and cliffs.

Back in the late 1960s and early 1970s, in the days of NASA’s manned Apollo flights to the Moon, no robot could decide which pebbles to pick up and bring home. But when the Apollo 17 astronaut Harrison Schmitt, the only geologist (in fact, the only scientist) to have walked on the Moon, noticed some odd orange soil on the lunar surface, he immediately collected a sample. It turned out to be minute beads of volcanic glass. Today a robot can perform staggering chemical analyses and transmit amazingly detailed images, but it still can’t react efficiently, as Schmitt did, to a surprise. By contrast, packed inside the field geologist are the capacities to walk, run, dig, hammer, see, communicate, interpret, and invent.

Of course when something goes wrong, an on-the-spot human being becomes a robot’s best friend. Give a person a wrench, a hammer, and some duct tape, and you’d be surprised what can get fixed. After landing on Mars, did the Spirit rover just roll right off its platform and start checking out the neighborhood? No, its airbags were blocking the path. Not until twelve more days had passed did Spirit’s remote controllers manage to get all six of its wheels rolling on Martian soil. Anyone on the scene on January 3 could have just lifted the airbags out of the way and in mere seconds given Spirit a little shove.

L
et’s assume, then, that we can agree on a few things: People notice the unexpected, react to unforeseen circumstances, and solve problems in ways that robots cannot. Robots are cheap to send into space but can make only a preprogrammed analysis. Cost and scientific results, however, are not the only relevant issues. There’s also the question of exploration.

The first troglodytes to cross the valley or climb the mountain ventured forth from the family cave not because they wanted to make a scientific discovery but because something unknown lay beyond the horizon. Perhaps they sought more food, better shelter, or a more promising way of life. In any case, they felt the urge to explore. It may be hardwired, lying deep within the behavioral identity of the human species. How else could our ancestors have migrated from Africa to Europe and Asia, and onward to North and South America? To send a person to Mars who can look under the rocks or find out what’s down in the valley is the natural extension of what ordinary people have always done on Earth.

Many of my colleagues assert that plenty of science can be done without putting people in space. But if they were kids in the 1960s, and you ask what inspired them to become scientists, nearly every one (at least in my experience) will cite the high-profile Apollo program. It took place when they were young, and it’s what got them excited. Period. In contrast, even if they also mention the launch of Sputnik 1, which gave birth to the space era, very few of those scientists credit their interest to the numerous other unmanned satellites and space probes launched by both the United States and the Soviet Union shortly after Sputnik.

So if you’re a first-rate scientist drawn to the space program because you’d initially been inspired by astronauts rocketing into the great beyond, it’s somewhat disingenuous of you to contend that people should no longer go into space. To take that position is, in effect, to deny the next generation of students the thrill of following the same path you did: enabling one of our own kind, not just a robotic emissary, to walk on the frontier of exploration.

W
henever we hold an event at the Hayden Planetarium that includes an astronaut, I’ve found there’s a significant uptick in attendance. Any astronaut will do, even one most people have never heard of. The one-on-one encounter makes a difference in the hearts and minds of Earth’s armchair space travelers—whether retired science teachers, hardworking bus drivers, thirteen-year-old kids, or ambitious parents.

Of course, people can and do get excited about robots. From January 3 through January 5, 2004, the NASA website that tracked the doings of the Mars rovers sustained more than half a billion hits—506,621,916 to be exact. That was a record for NASA, surpassing the world’s web traffic in pornography over the same three days.

The solution to the quandary seems obvious to me: send both robots and people into space. Space exploration needn’t be an either/or transaction, because there’s no avoiding the fact that robots are better suited for certain tasks, and people for others.

One thing is certain: in the coming decades, the United States will need to call upon multitudes of scientists and engineers from scores of disciplines, and astronauts will need to be extraordinarily well trained. The search for evidence of past life on Mars, for instance, will require top-notch biologists. But what does a biologist know about planetary terrains? Geologists and geophysicists will have to go too. Chemists will be needed to check out the atmosphere and test the soils. If life once thrived on Mars, the remains might now be fossilized, and so perhaps we’ll need a few paleontologists to join the fray. People who know how to drill through kilometers of soil and rock will also be must-haves, because that’s where Martian water reserves might be hiding.

Where will all those talented scientists and technologists come from? Who’s going to recruit them? Personally, when I give talks to students old enough to decide what they want to be when they grow up but young enough not to get derailed by raging hormones, I need to offer them a tasty carrot to get them excited enough to become scientists. That task is made easy if I can introduce them to astronauts in search of the next generation to share their grand vision of exploration and join them in space. Without such inspiring forces behind me, I’m just that day’s entertainment. My reading of history and culture tells me that people need their heroes.

T
wentieth-century America owed much of its security and economic strength to its support for science and technology. Some of the most revolutionary (and marketable) technology of past decades has been spun off the research done under the banner of US space exploration: kidney dialysis machines, implantable pacemakers, LASIK surgery, global positioning satellites, corrosion-resistant coatings for bridges and monuments (including the Statue of Liberty), hydroponic systems for growing plants, collision-avoidance systems on aircraft, digital imaging, infrared handheld cameras, cordless power tools, athletic shoes, scratch-resistant sunglasses, virtual reality. And that list doesn’t even include Tang.

Although solutions to a problem are often the fruit of direct investment in targeted research, the most revolutionary solutions tend to emerge from cross-pollination with other disciplines. Medical investigators might never have known of X-rays, since they do not naturally occur in biological systems. It took a physicist, Wilhelm Conrad Röntgen, to discover these light rays that could probe the body’s interior with nary a cut from a surgeon.

Here’s another example of cross-pollination. Soon after the Hubble Space Telescope was launched in April 1990, NASA engineers realized that the telescope’s primary mirror—which gathers and reflects the light from celestial objects into its cameras and spectrographs—had been ground to an incorrect shape. In other words, the two-billion-dollar telescope was producing fuzzy images.