“Space exploration is all about inspiration, innovation, and discovery. It’s about imagining the future. It’s about taking new steps, and exploring beyond our limitations, and creating something bigger and grander and better than ourselves. Along the way, there are countless benefits, invaluable discoveries, and technologies borne through the trials of exploration that enhance our lives on Earth. That’s been true for NASA’s first 50 years. And I have no doubt that it will be true in the next five decades.”
-NASA Deputy Administrator Shana Dale
Much of the celebration of NASA’s 50th anniversary focuses on the myriad of technological achievements made during those first five decades. But as Deputy Administrator Dale points out, there are many reasons to believe that more benefits, discoveries, and technologies are yet to come.
Putting humans back on the Moon and eventually on Mars will take new technologies — many already in development, but some not even thought of yet. Future spacecraft will require novel propulsion technologies and instrumentation, new rovers and robots, medical breakthroughs that will enable humans to live on other planets, and even new materials.
And while NASA’s vision for exploration of space continues to be a primary focus, the next 50 years also will see the development of new technologies that will improve our quality of life on Earth. Satellites and other missions that help us understand the Earth’s climate and how it continues to change, improved energy sources, cleaner cars, and safer air travel are just a few areas in which NASA has already made great strides, and which will continue into the future.
In more than 40 years of spaceflight, a lot has changed. The space shuttle is a luxury ship compared to the Mercury capsules that carried the first American astronauts into space. One thing that has changed very little, however, is the way rockets work. While different fuels have been used, the basic concepts are the same. But NASA researchers are currently working to change that.
Today’s spacecraft are still traveling at about the same speed that John Glenn did in 1962. One way to change that is the Variable Specific Impulse Magnetoplasma Rocket (VASIMR). Not only would VASIMR allow for faster space travel, but it would be able to travel to Mars much more quickly than a contemporary chemical-powered rocket, and then, once there, refuel on Mars for the return flight to Earth. The VASIMR engine could also help protect astronauts from the dangerous effects of radiation during their trip. In the less-distant future, VASIMR could help keep the International Space Station (ISS) in orbit without requiring extra fuel to be brought up from Earth.
VASIMR is a plasma-based propulsion system. An electric power source is used to ionize fuel into plasma. Electric fields heat and accelerate the plasma while the magnetic fields direct the plasma in the proper direction as it is ejected from the engine, creating thrust for the spacecraft. Possible fuels for the VASIMR engine include hydrogen, helium, and deuterium. Electrical power sources for the VASIMR engine could include nuclear power or solar panels.
Another craft, the Nano- Sail-D solar sail, is further along in its development, and is scheduled to travel to orbit onboard a SpaceX Falcon 1 rocket. The primary objective is to demonstrate successful deployment of a lightweight solar sail structure in low Earth orbit. NanoSail-D will feel two kinds of pressure: (1) aerodynamic drag from the wispy top of Earth’s atmosphere, and (2) the pressure of sunlight. If they can measure the solar pressure, they will have demonstrated solar pressure as a primary means of orbital maneuvering.
NASA also has begun the work to build the spacecraft, launch vehicles, and space systems that will enable the establishment of a lunar outpost sometime in the next 20 years. A new space transportation system for humans will make its first flight to the ISS by 2015, and first mission to the Moon by 2020. Orion, the vehicle that will carry the explorers, and Ares I, the rocket that will launch them, already are under development.
The Ares I crew launch vehicle and Ares V cargo launch vehicle are key components of NASA’s Constellation Program to develop new U.S. spacecraft and related systems and technologies for exploration of the Moon and other destinations. NASA is developing the technologies needed to return to the Moon for longer periods of time and conduct sustained research missions. In the new space economy, said NASA Administrator Michael Griffin, “every aspect of human knowledge will be tested and advanced: physics, chemistry, biology, and their practical applications in engineering, medicine, materials science, computer science, robotics, artificial intelligence, power, and many other fields — and we haven’t even mentioned rocket science.”
The spacecraft and systems NASA will use will build upon the foundation of proven designs and technologies used in the Apollo and space shuttle programs, while having far greater capacity and capability. The physics have not changed, but NASA’s moon mission is all new. This time, explorers are going back to stay. They will build an outpost in which they will live off the land and work for months at a time.
NASA also is considering small, pressurized rovers that could be key to productive operations on the Moon’s surface. Engineers envision rovers that would travel in pairs — two astronauts in each rover — and could be driven nearly 125 miles away from the outpost to conduct science or other activities. If one rover had mechanical problems, the astronauts could ride home in the other. Astronauts inside the rovers would not need to wear spacesuits because the pressurized rovers would be designed to protect crewmembers in a shirt-sleeve environment similar to the protection offered aboard the ISS. Spacesuits would be attached to the exterior of the rover.
A lunar outpost also has potential for improving human health. Sustained settlement on the Moon will mean new medical challenges. Those living in the lunar outpost will need new ways to treat injuries and illnesses, like telemedicine. They may even need new medical devices, since no space mission is likely to have a full staff of medical specialists aboard.
Space exploration drives the development of technologies with minimal impact on space, weight, and resources. These technologies include advanced recycling techniques, treating waste and converting it back into usable resources, and green power systems. Outposts on the Moon, as well as travel to Mars, will require lighter materials, manufacturing techniques with little waste or pollution, and better methods of recycling and reuse.
A great partnership of nations and industry will be needed to develop crucial technologies such as lunar habitats, power stations, scientific laboratories and facilities, radio and optical telescopes, human and robotic surface rovers, autonomous logistics and resupply vehicles, communication and navigation systems, on-site resource utilization equipment, and longduration life-support systems.
Spaceflight research is changing our understanding of how and why things burn, a scientific area scientists thought was relatively well established decades ago. A hydrogen experiment onboard Columbia’s final mission produced the weakest flames ever created — 100 times weaker than a birthday candle. This research could lead to cleaner-burning cars in the future by helping scientists improve the burning of hydrogen and other fuels in engines and furnaces.
The advanced energy field includes renewable energy sources that are important for future terrestrial and space development. NASA’s Glenn Research Center (GRC) is evaluating several demonstration projects to test, evaluate, and advance applications of wind turbines, fuel cells, and photovoltaics.
Producing power without damaging our environment is a continuing challenge. Fuel cells can have near-zero emissions, are quiet and efficient, and can work in any environment where the temperature is lower than the cell’s operating temperature.
GRC helped develop the alkaline fuel cells that are the primary source of power on the space shuttles and developed fuel cells for electric vehicles and energy-storage systems. Improved fuel cells may soon provide auxiliary equipment power on commercial aircraft. GRC is investigating three types of fuel cells: proton-exchange-membrane fuel cells (PEMFCs), regenerative fuel cell (RFC) systems, and solid-oxide fuel cells (SOFCs). PEMFCs promise to be more powerful, lighter, safer, simpler to operate, and more reliable. They will last longer, perform better, and may cost much less than current alkaline fuel cells. PEMFCs use hydrogen fuel and produce only water that is so pure that NASA plans to use it as drinking water for spacecraft crews. NASA PEMFCs may also produce electricity for spacesuits, airplanes, uninhabited air vehicles, and reusable launch vehicles.
In RFC systems, fuel cells use hydrogen and oxygen to produce electricity, water, and heat. Then a solar-powered electrolyzer breaks the water into hydrogen and oxygen so that the fuel cell can use it again. The waste heat is also used. SOFCs are being considered for power generation and for use in space because of their high efficiency, high power density, and extremely low pollution. SOFCs also are being developed for portable electronic devices, cars, and aircraft.
Monitoring Our Changing Climate
Currently, NASA has several Earth science missions in development. These missions will help measure: ocean topography (Ocean Surface Topography Mission, 2008); atmospheric carbon dioxide (Orbiting Carbon Observatory, 2008); global aerosol and cloud properties, along with total solar irradiance (Glory, 2009); sea surface salinity (Aquarius, 2009); global land cover change (Landsat Data Continuity Mission, 2011); and global rainfall from tropical to mid-latitudes (Global Precipitation Measurement, 2012).
Looking forward, the objective is to advance Earth system science to develop multi-decadal, global measurements of processes, especially of the oceans, since the ocean is the giant flywheel of the Earth system. About half the heat near the equator that goes off toward the poles is carried by the atmosphere and half is carried in the ocean.
NASA imagines a scenario for beyond 2016 that includes a technological leap in Earth observations to detect changes in the Earth system as they happen. NASA envisions using constellations of smart satellites placed in various orbits to augment airborne sensors and surfacebased sensors to form an integrated, interactive “sensor web” observing system. To make such a system possible, NASA has a technology investment program that will assure NASA has the instruments, information science, and components needed to take advantage of revolutionary mission architectures.
As more data from NASA missions becomes available, weather and climate forecasting capabilities are expected to increase dramatically from the current one- to two-day forecasts to one- to two-year forecasts within a decade, with a corresponding improvement in energy forecasts.
Another NASA environmental goal is to help determine how weather, climate, and other key environmental factors correlate with the occurrence of chronic and infectious diseases. Once verified, validated, and benchmarked, these relationships can be assimilated into surveillance systems to track and predict disease. NASA’s satellites offer a wealth of information for input into the support systems used for public health. The Terra and Aqua missions return information on such factors as vegetation, forests, flooding, wetlands, soil moisture, surface ultraviolet radiation and surface temperatures. The Tropical Rainfall Measuring Mission (TRMM) also provides important data on precipitation, which can be used to study different habitats. More missions are planned for the future that will return information related to public health issues, most notably the Global Precipitation Measurement (GPM) mission and the National Polar-orbiting Operational Environmental Satellite System (NPOESS).