Ralph Waldo Emerson once said, "Life is a journey, not a destination." The sentiment applies as much to life on Earth as it does to the search for life beyond it. On Wednesday, a research team led by NASA announced the discovery of seven Earth-sized planets in orbit around TRAPPIST-1, an ultracool dwarf star located nearly 40 light-years (about 378 trillion kilometers or 235 trillion miles) away. All seven planets may have liquid water on their surface, and three are located in the exoplanet system's habitable zone, the area that could sustain life, though researchers have yet to find evidence of either. Even if NASA confirms that life exists outside of our planet, it will likely be too far away for Earth's inhabitants to interact with it anytime soon. As the researchers acknowledged in their news conference, discovering life beyond Earth is not the point of looking for it. Instead, it's the process — and the discoveries and inventions born of it — that counts.
Since the V-2 rocket was first deployed in World War II, aeronautic and atmospheric research have been prized for their military applications. But deep space exploration, astrophysics and planetary science research have always been at the fringes of scientific research and, by extension, funding. The farther research efforts in the fields have ventured, quite literally, the more trouble governments have had determining their tangible benefits and justifying their continuation. NASA's budget has been in steady decline since the height of the space race with the Soviet Union during the Cold War. Furthermore, only a small portion of its budget — less than 30 percent this fiscal year — goes to space science, excluding human spaceflight.
Space missions beyond low-Earth orbit fall more or less into three categories. The first is long-range space exploration missions such as projects to send spacecraft to other bodies in our solar system. The second encompasses the study of Earth and planetary science, which NASA considers its bailiwick, while the third covers manned missions beyond Earth orbit. Because each category builds on the others, and all are inextricably linked, they are all equally valuable, even if the tangible benefits of each area aren't equally apparent. Planetary science, astrobiology and Earth science missions make up the platform of knowledge from which manned and long-range exploratory missions are launched. In the next several decades, travel to Mars or the outer solar system through unmanned — and perhaps even manned — missions will become easier and more frequent. But to undertake these kinds of ambitious endeavors, researchers must first answer fundamental questions about where to go, what to study and how. Closer to home, space exploration offers invaluable insight into how our planet works. The study of solar irradiance, for instance, is important for understanding Earth's climate and the degree to which it is changing.
Even the most basic space missions, moreover, yield technological breakthroughs and inventions that pave the way for advances in engineering. Missions often require cutting-edge developments in areas such as solar energy storage and communication technology, high-temperature alloys and cryogenics. For example, NASA and its partners are currently developing the James Webb Space Telescope, an observational platform that will be instrumental in determining whether life exists in the TRAPPIST-1 system. One of the telescope's most important tools, the Mid-Infrared Instrument, will require scientists to use advanced cryogenic techniques that can then be employed in a growing number of applications in everyday life on Earth.
The breakthroughs and discoveries that a long-range exploratory mission produces are even more expansive. The number of engineering problems that must be overcome to send someone to Mars is staggering. And many questions — such as how to clean laundry — are not as simple as they might seem at first glance. Only space exploration gives scientists the chance to devise and test solutions to these problems, many of which exist in one iteration or another on Earth. The innovations required to support human life over the course of long-term missions, for example, will doubtless have applications back home.
But space science is about more than new technologies or even discoveries. Practically every branch of science developed as an offshoot of another discipline. Astronomy probably evolved from the study of celestial bodies in religious or philosophical pursuits. After the scientific revolution some centuries later, mathematicians and physicists began sharing their views and adding to the field, laying the foundations of modern astronomy. When Galileo Galilei and Johannes Kepler first began looking at the sky, they could not have comprehended the applications that their findings would be used in centuries later. Today, the benefits of looking for life beyond Earth may seem elusive, but only time will tell what the journey has in store.