by Chris Impey
The Space Shuttle flew 135 times between 1981 and 2011, sending 300 astronauts into space. In its early years, it was used for a mixture of scientific and military payloads; in its later years, it was used to complete assembly of the International Space Station. It also served as a reminder of the danger and the high cost of space travel.17
On January 28, 1986, a nationwide TV audience was stunned when the Space Shuttle Challenger broke up and exploded in a clear blue winter sky, just seventy-three seconds after launch. Later investigation showed that a leak from an O-ring seal on one of the solid-fuel boosters had led to extreme aerodynamic stress on the spacecraft as it traveled at twice the speed of sound. Millions of schoolchildren were watching because NASA had selected Christa McAuliffe to be the first teacher in space. Chillingly, the crew cabin was intact as the vehicle broke up, so the seven crew members most likely died from subsequent impact in the ocean (Figure 13).18 The grief was repeated seventeen years later when the Space Shuttle Columbia disintegrated as it reentered the Earth’s atmosphere at twenty times the speed of sound. During launch, a piece of foam insulation had broken off from the external fuel tank and ruptured the leading edge of the left wing. Fourteen crew members died in these twin disasters.
The Space Shuttle was never as cheap and nimble as planned. Instead of the planned flight each week, the Shuttle managed one flight every two or three months. Over the course of the program, a launch cost about $1 billion, which works out to $80,000 per kilogram placed in orbit. Commercial entities were only able to use the Shuttle with massive subsidies from the government. The US military lost patience with the anemic launch schedule and the fact that two out of five orbiters had been lost catastrophically, so they developed their own heavy-lift capability using rockets without any astronauts.
Figure 13. The loss of the Space Shuttle Challenger seventy-three seconds after launch on January 28, 1986, led to the death of seven crew members. This incident and the death of seven aboard the Space Shuttle Columbia in 2003 are sobering reminders of the hazards of space travel.
However, the Space Shuttle did provide case studies in the importance of having astronauts rather than robots work in space. Robots are not versatile or reliable enough to match a well-trained astronaut. We can all admire the “seat-of-the-pants” problem-solving skills demonstrated by Neil Armstrong as he guided Apollo 11 over a boulder field with hardly any fuel left, and by the Apollo 13 crew as they nursed their crippled spacecraft around the Moon and home to safety. In particular, the five servicing missions of the Hubble Space Telescope defined the state of the art for astronauts, with multiple long space walks, challenging technical jobs, and difficult decisions made under time pressure. NASA administrator Mike Griffin had nixed a final Hubble servicing mission, worried about the risk to the astronauts. But in the end he determined that a robot servicing mission was so difficult that it was destined to fail, so astronauts were called on to give Hubble its final upgrade in 2009.
The choice between robots and humans is a false dichotomy. Machines are pathfinders and advance scouts, learning as much as they can and setting the stage for humans to eventually follow. We’ve explored the Solar System with robotic probes so far, but they’re limited in what they can do. Machines are extensions of us as we explore; when we eventually live in space, they will be our partners.
PART II
PRESENT
Wheel rats. That’s what Josefina calls those who never spend time in the Hub. Then we laugh. She’s my best friend; I love her mischievous smile and seditious sense of humor. Too many Pilgrims are aloof or self-important; they know we’re specially chosen and elite and they often act that way. A few have a messianic streak I find a little scary.
Floating in the Hub, the Earth is a blue-and-white bauble nestled in black velvet. It’s cozy and womblike. The Hub is the only zero-g place in the station; all the living and working quarters are around the rim of the wheel, spun to two-thirds g, which avoids the worst problems of bone loss and physiological adjustment. There are no real windows in the rim, since they would reveal the vertigo-inducing view of the Earth wheeling by every thirty seconds. Large panels set into the walls are programmed to display crisp holographic images of forest glades and mountain meadows. To me that’s more disorienting, since it’s such a disconnect from the reality of being 300 miles high, with only a thin titanium sheath separating us from the frigid, lung-busting vacuum of space.
The dreams still visit me; I can’t shake them. By day, I’m consumed with tasks and purpose, but I’m beginning to dread the nights.
The Overseers keep us busy to spare us from dwelling on what we’re about to do. The Moon and Mars are home to large colonies, researchers travel routinely as far as Jupiter and Saturn, and robot freighters ply the asteroid belt, but we’ve never severed the umbilical to the Solar System.
We know the risks. Space is unforgiving and humans are soft and fragile. Amid the high points, there have been disasters. I watched some of them play out as a kid. The orbiting research station was destroyed by a hail of micrometeorites. The first Europa lander was lost due to an orbital miscalculation, flung into deep space. The first Mars colony unraveled due to sectarian rivalries.
I miss my family but can’t imagine going back down. Mom and Sis are sharp and clear on-screen, but they’ve started to sound far off and disembodied. They told us to expect this, the withdrawing. Josefina says she cries most nights and I feel bad for her, then I feel bad I don’t feel the same way. The station is a metal carapace and we’re shrinking into it to bond with our new tribe.
We’re shocked when we hear who’ll be kicked off the station. With some we really saw it coming. Rajesh and Dimitri are abrasive and scheming. They’ve squandered all goodwill with their colleagues. The next to depart are another handful of malcontents, confederates, and henchmen of the ringleaders. There are others about whom we’ve had our suspicions. They share a haunted look and an inability to make eye contact. They’ve lost their stomach for the mission, and they have to go because our solidarity and sense of purpose is fragile. But there seems to be no rhyme or reason to the last group. Sonja is among them, and Pierre; we’ve laughed and shared good times with both of them. However, the profilers have picked them out and there is no arguing with the decision. Some subtle pattern of behavior has marked them as a threat. Josefina and I are on the way to dinner when we see them in the air lock of the shuttle bay. I’ll never forget the looks on their faces: angry, sullen, dazed, terrified.
They try to keep things upbeat. The piped music in common areas is soothing or jaunty. They lay on parties and celebrations to vary the routine. Messages from the Overseers are very carefully crafted and positive. And down below? From our vantage point, it’s a pretty planet. But the inmates on Earth are in charge of the asylum. All the tools exist to solve the world’s problems, but the fractious top species is squabbling and dithering.
Being on the station is in one sense timeless. No change in climate or vegetation gives a hint of the passage of days and weeks. Birthdays and festival days are forgotten or ignored. On the other hand, there’s a clear sense of time rushing forward to a vanishing point. That point has nearly arrived.
One evening, Josefina and I go to the Hub and pivot away from the Earth view to the opposite port and the blackness of space. As I float, I reach out and touch her fingertips with mine. Neither of us speaks. Above our heads are three sleek and black obelisks. They float alongside the station, perfectly parallel, poised for our destiny.
Ark 1. Ark 2. Ark 3.
4
Revolution Is Coming
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Space Doldrums
NASA has been in the doldrums.
The doldrums are a place, not a state of mind. In the eighteenth century, sailors knew the doldrums as a region near the equator where the prevailing winds might die for days or weeks, leaving sailing ships stranded on a glassy sea. NASA has also been becalmed, and its personnel and its supporters have experienc
ed the accompanying feelings of listlessness and stagnation.1
As our story moves from the past to the present, we first describe how far our aspirations have fallen in forty years—from the Moon landings between 1969 and 1972 to an inability to get an astronaut into low Earth orbit. We look at the difficulty of space travel, rooted in the implacable truth of the rocket equation. Then we see a glimmer of hope in the nascent space tourism industry. Last, we draw a parallel between the evolution of information technology and space technology, leading to optimism that resurgence is around the corner.
NASA’s lowest point was arguably the 2013 shutdown of the US Government, when 97 percent of its employees were furloughed, the highest percentage of the twenty-four federal agencies. Only a skeleton staff remained to ensure the safety of the crew on the International Space Station. Other activities halted immediately—no research was performed, no missions were planned, no e-mails were answered. It was a stark reminder that the exalted goal of space travel could easily be grounded by terrestrial politics.
The agency has also been struggling with decrepit infrastructure. In 2013, the Office of the Inspector General found that 80 percent of NASA’s facilities were more than forty years old and woefully out of date, and carrying maintenance costs of $25 million a year. What’s needed is far more than a coat of paint; the backlog of deferred maintenance totals $2.2 billion.2 NASA’s government funding has been shrinking for decades (Figure 14). For perspective, the bank bailout in 2008 cost more than has been spent on NASA since it was started in 1959. No bucks, no Buck Rogers.
Nothing epitomizes the malaise better than the Space Shuttle. By the time of the last flight in 2011, it represented forty-year-old technology. The launch rate ended up ten times lower than originally planned and the cost per launch twenty times higher. Two of the five orbiters suffered a catastrophic fate, with the loss of all on board. Apart from emblematic flights to launch and service the Hubble Space Telescope, most of the time the Shuttle served as an expensive limo to launch satellites and ferry construction materials to another high-priced and outmoded facility: the International Space Station. The Challenger and Columbia disasters are etched in the national psyche, and they have contributed to a widespread ambivalence about America’s space program.3 Since 2011, the United States has been unable to get astronauts into orbit without help from the Russians.
Figure 14. NASA’s share of the federal budget since the early 1960s. The rapid buildup for the Apollo program was unprecedented and unsustainable. Since then, there has been a steady decline, apart from a slight rise at the peak of Space Shuttle and International Space Station activity.
In addition to the fairly frosty relations between the two countries, the Russians have their own problems.
After the fall of the Soviet Union, the Russian space program suffered from diminished budgets and a lack of innovation.4 In 1965, the Soviets invented the Proton rocket to launch ICBMs, and they still use variations of the original design. In recent years, the Russians have suffered seven mission failures. In 2010, three satellites crashed into the Pacific Ocean. In 2011, a resupply mission to the International Space Station exploded over Siberia in a spectacular fireball, forcing the six waiting astronauts to dig deep into their reserves of food and water. In 2013, another three satellites were lost in an explosion that rained hundreds of tons of toxic debris on the launch site. Yuri Karash, a member of the Russian Space Academy, compared Russian rocket development to attempting to upgrade a steam engine: “You equip it with a computer. . . . You equip it with air conditioning. You put a locomotive driver with a university degree in the cabin, and it will still be the same steam locomotive.”5 The Russian Government audit agency noted that money intended for the space program had simply been stolen.
At the Baikonur Cosmodrome, on the steppes of western Kazakhstan, the decay is obvious. Baikonur is where Sputnik was launched, and where Yuri Gagarin and Laika made history. But today, nomadic herders occupy the many vacant buildings and the town struggles with heroin smuggling and radical jihadists. American, European, and Japanese astronauts arrive at the launch site via a rutted road where camels have the right of way. But they keep on arriving because it’s their only way up.
Meanwhile, NASA’s generally successful program to send out robotic probes to explore the Solar System is also under stress. The budget for planetary science is falling. Complex interplanetary probes cost a couple of billion dollars each and the budget only has enough slack to fund a couple of missions per decade.6 A more fundamental problem involves plutonium. Since the 1970s, almost everything we’ve learned about the outer planets and their moons has relied on power from heat released by the radioactive isotope plutonium-238. Solar power is too feeble and chemical batteries are too inefficient, so this by-product of nuclear reactors (which cannot be used to make a bomb) is the go-to super-fuel. But poor planning and false promises from Russia have left NASA with barely enough plutonium to power missions for the next few years. The nuclear crisis is so bad that affected researchers call it “The Problem.”
Communication is another mundane but basic problem. When you watch a silly cat video on YouTube, you give little thought to how the data got to your computer, apart from being dimly aware that the video is really a stream of ones and zeros. In fact, videos and e-mails and data aren’t transmitted whole. They’re disassembled into packets of data, distributed worldwide via optical fiber and radio waves over a network of networks, and reassembled at your computer or handheld device—rather like digital sausages. It works well for Earth-bound humans, so why would it be hard for an astronaut to watch cat videos on the Moon or Mars?
First, it takes light or radio waves anywhere from four to twenty-one minutes to reach Mars from Earth, depending on where the two planets are in their orbits. NASA engineers don’t control the Mars rovers like a video game enthusiast would, flicking a joystick as the rover careens across sand dunes. The rovers are controlled painstakingly by commands that are separated by a half hour or more to allow for the round-trip signal time. Second, planets rotate and shadow the orbiters, so there are dead times when no communication is possible. Third, these interruptions and delays cause technical problems because the Internet paths are in constant flux; if a packet of data sits around too long before its partners arrive, it’s discarded. At the moment, the Internet can’t be extended into the Solar System. Luckily, the “Father of the Internet” is on the job. Vinton Cerf, designer of the original protocols for the Internet in 1973, is working with NASA on the next-generation system that will operate seamlessly across billions of miles.7
However, when one is becalmed in the doldrums, the real problem isn’t money or communication. A more fundamental problem is propulsion.
Principles of Flight
Why is space travel so difficult? It’s just a matter of accelerating an object to 17,650 mph, as Newton conjectured. But that’s as reductive as saying the Mona Lisa is just a picture of a smiling woman. A general description gives no sense of the complexity and subtlety of the work.
On the dead calm sea, a breeze springs up, ruffling the water and soothing your fevered brow. As humans have known for millennia, if you can catch this breeze in cloth or canvas, it will propel you forward. Large ships from the Romans through the Vikings used square sails to catch the wind, augmented by men pulling oars. But sailors plying the Mediterranean more than a thousand years ago discovered through experimentation that triangular sails allowed a boat to sail almost into the wind, and this capability was enhanced with multiple sails. Whereas a square-rigger can’t move downwind faster than the speed of the wind that’s pushing it, a modern yacht can sail several times the wind speed, even when it’s almost pointing into the wind.
The explanation was provided in 1738 by the Swiss scientist Daniel Bernoulli, a member of an illustrious family of mathematicians and scientists. The physical principle states that in any fluid flow, an increase in the speed of the fluid is accompanied by a decrease in pressure. Wind forced to
travel over the curved surface of a sail must travel faster than wind moving behind the sail; the decrease in pressure on the front face of the sail creates a force that drives the boat forward.
Now imagine that the sail is horizontal. If it can be propelled through the air, it will experience that same force in an upward direction. The principles of flight are based on Newtonian physics, refined over several hundred years.
A flying object such as a bird, a plane, or a rocket is engaged in a constant tug of war among opposing forces. The downward force is the inescapable foe: gravity. The upward force is lift, provided by air flowing over a wing. The forward force is thrust, provided by muscles for birds and engines for planes. It’s opposed by drag, the resistance from the air, which can be minimized by careful aerodynamic design.
Human flight began with balloons. With a balloon, thrust comes from the whims of the wind and lift comes from the buoyancy of a gas less dense than air. The Chinese developed hot-air balloons for military signaling in the third century, at the same time that they were developing “fire arrows.” In 1783, Jean-François de Rozier and the Marquis d’Arlandes became the first humans to fly, traveling five miles across the French countryside in a balloon designed by the Montgolfier brothers. They had to petition King Louis XVI for the honor, since he had originally decreed that condemned criminals would be the first test pilots. Balloons reach their limit at the height where even the lightest gas, helium, can’t provide buoyancy in the thin air. Austrian daredevil Felix Baumgartner got close to this limit in 2012 when he ascended to 24 miles in a balloon that was three times the height of a commercial jet. He took the quick route down, leaping from the balloon in a pressurized suit. In his four-minute-long free fall, he broke the sound barrier and reached a speed of 844 mph.8