Long-time residents of Florida’s northeastern Space Coast, a region that includes the NASA launch pads at Cape Canaveral, can follow the history of NASA’s space vehicles by looking out their windows. Coastal beaches offer better views of the rockets ascending over the Atlantic, but the rockets’ raw power is best gauged by how hard the region’s windowpanes rattle during liftoff.
According to the windowpane scale, NASA has fallen from the zenith of its heavy-lifting might. The space shuttles, which have been ferrying astronauts and cargo into low Earth orbit since 1982, can lift only about 20 percent as much as the enormous Saturn V rockets that took the Apollo astronauts to the Moon. Strong as they are, the three remaining space shuttles cannot lift astronauts beyond low Earth orbit. But they were designed with a different goal than the Apollo rockets: to be reusable workhorses of modern human space flight, and they have been largely successful in that endeavor. Shuttle missions have carried much of the 440-ton International Space Station to orbit, where its prefabricated modules are assembled, launched the Hubble Space Telescope in 1990, and performed two daring repair missions on the Hubble in 1993 and 2009.
But the shuttles’ days are numbered. After the loss of the Shuttle Columbia during atmospheric re-entry in 2003, NASA suspended the shuttle program. Less than a year after the accident, President Bush announced a new vision for the future of American space exploration. This plan called for NASA to retire the aging shuttle fleet in 2010, after a total of 134 flights, and build a new generation of rockets.
The planned vehicle for human space flight, called Orion, is intended to replace the shuttles by 2015, return Americans to the moon by 2020, and make it to Mars some time after that. To make this happen, NASA is planning to build a new generation of heavy lifting rockets that will surpass even the Apollo-era rockets’ power. But as improving technology enables NASA to get more scientific data from unmanned robotic probes, the agency must weigh the excitement of human space exploration against its huge risk and expense.
A fatal piece of orange foam
The pivotal event for space travel in the Aughts occurred in the bright blue Texas sky on the morning of February 1, 2003. As the Shuttle Columbia reentered Earth’s atmosphere after 15 days spent conducting scientific experiments in microgravity, sensors on the leading edge of the shuttle’s left wing began to show an unusual amount of strain. As NASA mission controllers watched temperature sensors shoot into dangerous territory, amateur observers along the flight path from California to Texas saw bright flashes and trails of smoke following the passing shuttle. Within minutes, Columbia had disintegrated, and the crew of six Americans and one Israeli was lost. National Weather Service radar picked up a bright red trail of debris above Texas and Louisiana before thousands of pieces of the shuttle, science experiments, and human remains fell from the sky.
Following the accident, NASA suspended the shuttle program while conducting an investigation. Information relayed from onboard sensors indicated that a breach in the orbiter’s insulating tiles was responsible for the midair disintegration. These tiles were intended to protect the shuttle from the super-heated plasma of atmospheric gas that normally surrounds spacecraft during reentry. Video analysis of the shuttle’s launch showed that several large pieces of insulating foam had fallen off of the shuttle’s iconic orange external fuel tank and struck the wing, fatally damaging some of the insulating tiles.
Just as after the 1986 Challenger disaster, when another shuttle exploded above Florida 73 seconds after liftoff, the NASA investigation revealed systemic human problems at mission control. Although flight engineers had expressed concerns during the mission about the foam strike, which had been observed during liftoff, no action was ever taken. Had mission controllers instructed the astronauts to perform a spacewalk to inspect the extent of Columbia’s damage, NASA might have been able to undertake a rescue mission or orchestrate an in-flight repair. Instead, the investigators’ report revealed a devastating complacency and poor communication among members of the shuttle team.
It took nearly 30 months for the shuttle to return to flight, a period that left the astronauts aboard the International Space Station without their primary means of resupply and transport. When the Shuttle Discovery returned to the station in late July 2005, the astronauts were responsible for testing several new safety procedures designed to prevent a repeat of the Columbia disaster. Despite new equipment designed to keep the external fuel tank from losing insulating foam during liftoff, cameras recorded several large pieces careening down the length of the ship. The new inspection of insulating tiles showed that the lost foam did no damage, but it revealed other problems on the Discovery’s underside. Reflecting NASA’s more conservative approach to safety, controllers had astronaut Steve Robinson perform an unplanned spacewalk and complete the shuttle’s first in-flight repair. By the time the crew returned to Earth, NASA had already decided to postpone upcoming flights for an additional year.
To the moon, and beyond
When Bush announced his “Vision for Space Exploration” in the wake of the Columbia disaster, he returned the space program’s focus to landing on other worlds. Bush’s plan called for NASA to retire the space shuttle program as soon as it met its obligations to the group of countries involved in building the International Space Station. He proposed beginning an effort called the Constellation program, which would rely on the yet-to-be-built Orion spacecraft to carry astronauts to the Moon. Ultimately, the Constellation program is intended to establish a permanent lunar base that could be used as a jumping-off point for manned missions to Mars. In recent years, however, funding has not kept pace with the astronomical costs of the program, slowing the development of new technologies.
The strategy calls for the development of two new rockets. The Ares V rocket—slated to be nearly 60 percent more powerful than the Apollo-era Saturn Vs—would carry a supply ship up to orbit Earth. About 90 minutes later, the weaker Ares I would bring the Orion crew vehicle up to rendezvous with the supply ship in orbit. To simplify the shift, the Ares I has a design based on the space shuttle’s solid rocket boosters and main engines. In October, an unmanned prototype Ares I-X launched successfully from Cape Canaveral.
The Constellation Program has met a great deal of criticism. Some politicians fear the inevitable job losses that ending NASA’s shuttle program entails; in 2008, NASA estimated that as many as 8,000 private and public sector positions would be eliminated with the shuttle program. Politicians have also publicly fretted about the impending gap of at least five years, during which the United States will have no capacity for independent human space flight. To reach the International Space Station during this time, NASA will be forced to buy its astronauts seats on Russian Soyuz rockets.
In September, a panel of experts appointed by President Obama to review the future of American space policy released its unflattering report of the Constellation project. They criticized the plan as unworkable, especially considering the budget shortfalls facing NASA in upcoming years. The panel suggested that NASA skip attempts to land on either the Moon or Mars and instead embark on longer missions in deep space. This would avoid the costs of developing landing equipment and sending enough fuel to liftoff from another planet’s gravity well. The current Ares-Orion plan is estimated to cost taxpayers $230 billion over the next two decades, according to Congress’ General Accountability Office. President Obama has yet to make a definitive statement himself about the future of NASA.
Some scientists have also criticized the aspirations of the Constellation program as more grandiose than useful. In recent years, NASA’s robotic missions have returned reams of scientifically useful data from Mars, the Moon, and deep space. As robotic technology continues to improve, many question whether the risk and expense of human space travel is worth it. Indeed, NASA has had some failures of unmanned missions far from home—including a probe that smashed into the surface of Mars instead of landing, and a rover that is currently stuck in a Martian sand trap—but without the loss of astronauts, the only price is embarrassment and taxpayer dollars.
Bush’s space policy called for extensive use of robots as scouts to investigate possibilities for human exploration and colonization. The relatively low price of unmanned probes, rovers, and satellites currently allows NASA to maintain a busy schedule of scientific missions even with expenses from the shuttle program.
For example, Brown University geologist Peter Schultz, the co-investigator of a recent mission called Lcross, announced in November that there is water in the form of ice on the Moon. The mission slammed a probe into a lunar crater while another Lcross vehicle analyzed the resulting dust plume for evidence of water. This water would be an important resource for any long-term human installation on the Moon. And the whole Lcross mission cost NASA only $79 million, about half the price of the recent Wolverine movie, according to Schultz.
Even in light of NASA’s success with unmanned missions, Schultz said that the decision of whether to recommit the country to human exploration is not a strictly scientific one. “Something that is this expensive—to go for a human presence in space—is not a scientific decision. That is largely a decision that is made on either political grounds or on the basis of a mandate at very high levels,” he said.
Indeed, the benefits of a massive space exploration effort are rarely apparent until afterwards. Beyond national pride, scientific data, and moon rocks, the Apollo program encouraged a generation of students to pursue science and engineering degrees. Today, educational dividends from China’s burgeoning space program, which in 2003 became the third to send a human into orbit, are trickling down even to grade schools. And despite the high cost of human space flight—in both resources and lives—a majority of Americans continue to support it. And compared to trillions of dollars spent on two seemingly endless wars, NASA seems to be a good investment.
If we’re going to Mars, NICK WERLE B’10 wants in.