Space Chronicles: Facing the Ultimate Frontier (20 page)

That was bad.

As if to make lemonade out of lemons, though, computer algorithms came to the rescue. Investigators at the Space Telescope Science Institute in Baltimore, Maryland, developed a range of clever and innovative image-processing techniques to compensate for some of Hubble’s shortcomings. Turns out, maximizing the amount of information that could be extracted from a blurry astronomical image is technically identical to maximizing the amount of information that can be extracted from a mammogram. Soon the new techniques came into common use for detecting early signs of breast cancer.

But that’s only part of the story.

In 1997, for Hubble’s second servicing mission (the first, in 1993, corrected the faulty optics), shuttle astronauts swapped in a brand-new, high-resolution digital detector—designed to the demanding specs of astrophysicists whose careers are based on being able to see small, dim things in the cosmos. That technology is now incorporated in a minimally invasive, low-cost system for doing breast biopsies, the next stage after mammograms in the early diagnosis of cancer.

So why not ask investigators to take direct aim at the challenge of detecting breast cancer? Why should innovations in medicine have to wait for a Hubble-size blunder in space? My answer may not be politically correct, but it’s the truth: when you organize extraordinary missions, you attract people of extraordinary talent who might not have been inspired by or attracted to the goal of saving the world from cancer or hunger or pestilence.

T
oday, cross-pollination between science and society comes about when you have ample funding for ambitious long-term projects. America has profited immensely from a generation of scientists and engineers who, instead of becoming lawyers or investment bankers, responded to a challenging vision posed in 1961 by President John F. Kennedy. Proclaiming the intention to land a man on the Moon, Kennedy welcomed the citizenry to aid in the effort. That generation, and the one that followed, was the same generation of technologists who invented the personal computer. Bill Gates, cofounder of Microsoft, was thirteen years old when the United States landed an astronaut on the Moon; Steve Jobs, cofounder of Apple Computer, was fourteen. The PC did not arise from the mind of a banker or artist or professional athlete. It was invented and developed by a technically trained workforce, who had responded to the dream unfurled before them and were thrilled to become scientists and engineers.

Yes, the world needs bankers and artists and even professional athletes. They, among countless others, create the breadth of society and culture. But if you want tomorrow to come—if you want to spawn entire economic sectors that didn’t exist yesterday—those are not the people you turn to. It is technologists who create that kind of future. And it is visionary steps into space that create that kind of technologist. I look forward to the day when the solar system becomes our collective backyard—explored not only with robots, but with the mind, body, and soul of our species.

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CHAPTER EIGHTEEN

THINGS ARE LOOKING UP
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O
n September 8, 2004, the scientific payload from NASA’s Genesis mission crashed into the Utah desert at nearly two hundred miles per hour after its parachutes failed to open. The spacecraft had spent three years orbiting the Sun at a distance of nearly a million miles from Earth, collecting some of the tiny atomic nuclei that the Sun expels continuously into space, and whose abundances encode the original composition of the material from which the solar system formed 4.6 billion years ago. NASA scientists have recovered some of the results from Genesis, and thus avoided writing off their time and our $260 million as a total loss.

But even if no usable data had returned, this single failure merely emphasizes how well we are doing as we explore the cosmos. NASA’s two robotic geologists roving the surface of Mars have both exceeded their scheduled lifetimes while returning stunning images of the Martian surface—images that tell us Mars once had running water and large lakes or seas. The Mars Global Surveyor, likewise operating well beyond its planned lifetime, continues to orbit the Red Planet and send us high-resolution images of the Martian surface. And the European Space Agency’s Mars Express Orbiter has supplied evidence of methane in the Martian atmosphere, which may be traceable to active underground bacterial colonies. The Cassini spacecraft orbits Saturn, and Cassini’s Huygens probe detached and then descended through the smoggy atmosphere of Saturn’s largest moon, Titan, landed on its surface, and confirmed the existence of liquid lakes of methane. Titan itself may well prove to be a site for life of a different kind. We also have MESSENGER, the first probe to orbit the Sun’s innermost planet.

When we turn to the much vaster cosmos beyond our solar system, we find a stunning array of spacecraft that orbit Earth outside our interfering atmosphere. NASA’s orbiting Chandra X-ray Observatory detects X-rays from distant venues of cosmic violence, such as the turbulent environs that surround hungry black holes, while NASA’s Spitzer Space Telescope maps infrared light, a calling card of young stars and star-forming regions. The European Space Agency’s Integral satellite studies gamma rays, the highest-energy form of light, which arise from exploding stars and other violent cosmic events; NASA’s Swift Gamma Ray Burst Explorer searches for the most distant gamma-ray outbursts in the universe. Meanwhile, the Hubble Space Telescope will continue to work until its larger successor, the James Webb Space Telescope, reaches orbit, peering farther than any previous telescope as it chronicles the formation of galaxies and the large-scale structures they trace.

Enlightened by our surrogate eyes in this busy vacuum of space, we should occasionally remind ourselves that Earth’s continents display no national boundaries. But above all else, our smallness in the vastness of the universe should humble us all.

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CHAPTER NINETEEN

FOR THE LOVE OF HUBBLE
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T
he Hubble Space Telescope, the most productive scientific instrument of all time, had its fifth and final repair mission in the spring of 2009. The space shuttle astronauts launched from Kennedy Space Center in Florida, matched orbits with the telescope, captured it, serviced it, upgraded it, and replaced its broken parts—on the spot.

Roughly the size of a Greyhound bus, Hubble was launched aboard the space shuttle Discovery in 1990 and has substantially outlived its initial ten-year life expectancy. For students in high school today, Hubble has been their primary conduit to the cosmos. The final servicing mission extended Hubble’s life several years. Among other things, it replaced burned-out circuit boards in the Advanced Camera for Surveys. That’s the instrument responsible for Hubble’s most memorable images since its installation in 2002.

Servicing Hubble requires exquisite dexterity. I recently had the opportunity to visit NASA’s Goddard Space Flight Center in Maryland. There I donned puffy, pressurized astronaut gloves, wielded a space-age portable screwdriver, stuck my head in a space helmet, and attempted to extract a faulty circuit board in a mock-up of the failed camera, which was embedded within a full-scale model of the Hubble. This was a darn near impossible feat. And I wasn’t weightless. I was not wearing the full-body spacesuit. Nor were Earth and space drifting by.

Normally we think of astronauts as brave and noble. But in this case, having the “right stuff” includes being a hardware surgeon.

Hubble is not alone up there. Dozens of space telescopes of assorted sizes and shapes orbit Earth and the Moon. Each one provides a view of the cosmos that is unobstructed, unblemished, and undiminished by Earth’s turbulent and murky atmosphere. But most of these telescopes were launched with no means of servicing them. Parts wear out. Gyroscopes fail. Coolant evaporates. Batteries die. Hardware realities limit a telescope’s life expectancy.

All these telescopes advance science, but most perform their duties without the public’s awareness or adulation. They are designed to detect bands of light invisible to the human eye, some of which never penetrate Earth’s atmosphere. Entire classes of objects and phenomena in the cosmos reveal themselves only through one or more invisible cosmic windows. Black holes, for example, were discovered by their X-ray calling card—radiation generated by the surrounding, swirling gas just before it descended into the abyss. Telescopes have also captured microwave radiation—the primary physical evidence for the Big Bang.

Hubble, on the other hand, is the first and only space telescope to observe the universe using primarily visible light. Its stunningly crisp, colorful, and detailed images of the cosmos make Hubble a kind of supreme version of human eyes in space. Yet its appeal derives from much more than a stream of pretty portraits. Hubble came of age in the 1990s, during exponential growth of access to the Internet. That’s when its digital images were first cast into the public domain. As we all know, anything that’s fun, free, and forwardable spreads rapidly online. Soon Hubble images, one more splendorous than the next, became screensavers and desktop wallpaper for computers owned by people who would never before have had the occasion to celebrate, however quietly, our place in the universe.

Indeed, Hubble brought the universe into our backyard. Or rather, it expanded our backyard to enclose the universe itself, accomplishing that with images so intellectually, visually, and even spiritually fulfilling that most don’t even need captions. No matter what Hubble reveals—planets, dense star fields, colorful interstellar nebulae, deadly black holes, graceful colliding galaxies, the large-scale structure of the universe—each image establishes your own private vista on the cosmos.

Hubble’s scientific legacy is unimpeachable. More research papers have been published using its data than have ever been published for any other scientific instrument in any discipline. Among Hubble’s highlights is its settling of the decades-old debate about the age of the universe. Previously, the data were so bad that astrophysicists could not agree to within a factor of two. Some thought ten billion years; others, twenty billion. Yes, it was embarrassing. But Hubble enabled us to measure accurately how the brightness varies in a particular type of distant star. That information, when plugged into a simple formula, provides that star’s distance from Earth. And because the entire universe is expanding at a known rate, we can then turn back the clock to determine how long ago everything was in the same place. The answer? The universe was born 13.7 billion years ago.

Another result, long suspected to be true but confirmed by Hubble, was the discovery that every large galaxy, such as our own Milky Way, has a supermassive black hole at its center that dines on stars, gas clouds, and other unsuspecting matter that wanders too close. The centers of galaxies are so densely packed with stars that atmospherically blurred Earth-based telescopes see only a mottled cloud of light—the puddled image of hundreds or thousands of stars. From space, Hubble’s sharp detectors allow us to see each star individually and to track its motion around the galactic center. Behold, these stars move much, much faster than they have any right to. A small, unseen yet powerful source of gravity must be tugging on them. Crank the equations, and we are forced to conclude that a black hole lurks in their midst.

In 2004, a year after the Columbia tragedy, NASA announced that Hubble would not receive its last servicing mission. Curiously, the loudest voices of dissent were from the general public. Akin to a modern version of a torch-wielding mob, they voiced their opposition in every medium available, from op-eds to petitions. Ultimately, Congress listened and reversed the decision. Democracy had a shining moment: Hubble would indeed be serviced one last time.

Of course, nothing lasts forever—nothing except, perhaps, the universe itself. So Hubble eventually will die. But in the meantime, the James Webb Space Telescope beckons, designed to see deeper into the universe than Hubble ever could. When launched, funding permitting, it will allow us to plumb the depths of gas clouds in our own Milky Way galaxy in search of stellar nurseries, as well as to probe the earliest epochs of the universe in search of the formation of galaxies themselves.

NASA retired the aging space shuttle in 2011. Given sufficient political will, this step should enable its aerospace engineers, assembly lines, and funding streams to focus on a new suite of launch vehicles designed to do what the shuttles can’t: take us beyond low Earth orbit, with sights on farther frontiers.