In 1820, the British Royal Navy was the largest in the world, with so many ships that one extra 10-gun brig-sloop lay idle for more than half a decade before it was refitted to conduct hydrographic surveys. She embarked on several voyages, but it was her second trip that catapulted the ship into world-wide renown. Nearly 200 years later schoolchildren learn her name in history and biology classes.
That ship was the H.M.S Beagle—built for one mission but repurposed to do another.
On its second voyage, the Beagle hosted the recently graduated naturalist Charles Darwin. Over the years during which the survey work was carried out, Darwin spent as much time as possible on shore, studying local geology, natural history and ethnology. He gained fame by publishing his diary, The Voyage of the Beagle. More importantly, his findings were pivotal in the formation of his scientific theories on natural selection and evolution, irreversibly changing our worldview.
Like the repurposed Beagle, NASA’s new Space Launch System (SLS), designed to send humans beyond Earth’s orbit, can also serve another purpose: It can carry robotic spacecraft to the furthest reaches of our solar system.
The dual use of NASA’s rockets for both human spaceflight and robotic science missions is not new; its roots reach back to the Apollo program. James Webb, sometimes called the “architect” of Apollo, was a staunch supporter of robotic missions. In a letter to President Kennedy, he wrote: “The objective of our national space program is to become preeminent in all important aspects of this endeavor and to conduct the program in such a manner that our emerging scientific, technological, and operational competence in space is clearly evident.” Under Webb’s watch, NASA flew more than 75 science missions.
Following Apollo, the era of the space shuttle not only brought us the crewed International Space Station; it also brought us the iconic Hubble Space Telescope, carried aloft with a crew of astronauts aboard the shuttle Discovery. At first, the Hubble looked like a disaster: its light-gathering mirror had been ground to perfection—but with the wrong curvature, making it incapable of making sharp images. But those flawed optics were corrected by astronauts on a later shuttle flight, and subsequently upgraded five times, by astronauts performing the most complex space walks ever choreographed by humankind.
Because of this interwoven tapestry of science and human spaceflight, Hubble revolutionized not only what we understand about the cosmos, but also how we understand it. As important, NASA’s commitment to an enduring science program has provided a steady cadence of breathtaking feats and discoveries, including landing rovers on Mars and sending out probes that orbited Saturn; flew past Pluto; mapped Mercury in astonishing detail; delivered images of galaxies from our infant universe; established that almost every star in the night sky has its own planetary system; and more. This steady stream of science-driven accomplishments has sustained American (indeed, global) public interest in our nation’s space agency.
Today, we are witnessing a renaissance of U.S. space launch investment. From the first super-heavy lift vehicle in more than 50 years—the NASA Space Launch System (SLS)—to the new commercial launch vehicles both small and large, flight opportunities for science missions are increasing.
A parallel renaissance is taking place in the field of planetary science. In just a few short years, we have expanded our knowledge from just our lone solar system, around an average star, to identifying literally thousands of planetary systems. We’ve suspected for millennia that our planet was not unique. We now know for a fact that our local neighborhood teems with planets large and small; warm and cold; some uninhabitable, but some, perhaps just a few, with conditions amenable to life as we know it.
Scientists can now envision the tool we will need to find the habitable planets around other stars. It is bold and ambitious: a space-based telescope with diameter perhaps twice that of the James Webb Space Telescope. We will need a big rocket like SLS, to lift this telescope; perhaps we might even need to build it in space. The largest rockets in our future fleet not only can change the perspective of humanity by landing us on the moon and Mars; they can loft the instruments we need to find new shores for exploring. Just as Darwin’s scientific research on the Beagle changed our world view, our modern explorations may reveal that evolution has occurred not just here at home but elsewhere in the universe.
SLS and its commercial kin will also be able to propel new robotic spacecraft through the intriguing water plumes that spew from subsurface oceans on Jupiter’s icy moon Europa and Saturn’s Enceladus. We suspect that oceans of water are also hiding beneath surfaces of Pluto and its fraternal twin Triton, a moon of Neptune that once roamed free before being captured by the eighth planet. The unprecedented lift and capacity of SLS will, once it’s been built and successfully tested, game-changing benefits for new spacecraft, including the ability to traverse the distances to the outer solar system in significantly reduced time.
Nineteenth-century Britain invested in its navy for economic and strategic security, yet the legacy of the HMS Beagle transcended those original purposes. In this century, the United States is investing in NASA for national strategic interests, but also to push once again on the boundaries of exploration, and to achieve a sustainable presence on the moon and beyond.
As we contemplate the fleet required for these next phases of NASA’s journey into space, let’s leave room for modern-day Darwins. Although he was given only one small cabin on the Beagle’s second survey mission, today’s schoolchildren know about that voyage because of his feats of scientific exploration. It could be that history books published 200 years from now will teach children that a 21st-century Beagle enabled scientific exploration of our solar system, and perhaps even lofted the telescope that finally found life elsewhere in the Milky Way—the story of how powerful rockets enabled scientific exploration of our solar system, and perhaps even lofted the telescope that finally found life elsewhere.