We will go back to the Moon to learn more about what it will take to support human exploration to Mars and beyond. We will continue to nurture the development of a vibrant low-Earth orbit economy that builds on the work done to date by the International Space Station. NASA engineers will develop new technologies to improve air transport at home and meet the challenges of advanced space exploration.
Our scientists will work to increase an understanding of our planet and our place in the universe. Unlike the way the space program started, NASA will not be racing a competitor. Rather, we will build upon the community of industrial, international, and academic partnerships forged for the space station.
Commercial companies will play an increasing role in the space industry: launching rockets and satellites, transporting cargo and crew, building infrastructure in low-Earth orbit. NASA will continue to be a global leader in scientific discovery, fostering opportunities to turn new knowledge into things that improve life here on Earth.
It will consist of at least a power and propulsion element as well as habitation, logistics, and airlock capabilities. The power and propulsion element will be the first component to launch for placement near the Moon in , with additional elements launching in subsequent years. In the half-century since people visited the Moon, NASA has continued to push the boundaries of knowledge to deliver on the promise of American ingenuity and leadership in space.
These experiences and partnerships will enable NASA to go back to the Moon in — this time to stay. With its partners, NASA will use the Gateway lunar command module orbiting the Moon as a staging point for missions that allow astronauts to explore more parts of the lunar surface than ever before. Ongoing research and testing of new aeronautics technologies are critical in these areas and will help the U.
Developing quiet supersonic transport over land, and quieter, cleaner aircraft technologies are two ways NASA is transforming aviation.
The X will be the first all-electric X-plane and will be flown to demonstrate the benefits that electric propulsion may yield for the future of aviation. The goal of the X is to achieve a percent increase in high-speed cruise efficiency, zero in-flight carbon emissions, and flight that is much quieter for the community on the ground.
Wells — , wrote about technologies that explore the dream of traveling beyond Earth into space. Humans did not reach space until the second half of the 20th century. However, the main technology that makes space exploration possible, the rocket , has been around for a long time. A rocket is propelled by particles flying out of one end at high speed.
We do not know who built the first rocket, or when, but there are records of the Chinese using rockets in war against the Mongols as early as the 13th century.
The Mongols then spread rocket technology in their attacks on Eastern Europe. Early rockets were also used to launch fireworks and for other ceremonial purposes. Rockets were used for centuries before anyone could explain exactly how they worked.
To better understand this law, consider the skate boarder in Figure below. When the skate boarder pushes the wall, his force — the action — is matched by an equal force by the wall on the skate boarder in the opposite direction — the reaction.
Once the skate boarder is moving, however, he has nothing to push against and he will soon stop because of friction. Imagine now that he is is holding a fire extinguisher.
When he pulls the trigger on the extinguisher, a fluid or powder flies out of the extinguisher, and he moves backward. In this case, the action force is the pressure pushing the material out of the extinguisher. The reaction force of the material against the extinguisher pushes the skate boarder backward.
Since space is a vacuum, how does a rocket work if there is nothing for the rocket to push against? A rocket in space moves like the skater holding the fire extinguisher. Fuel is ignited in a chamber, which causes an explosion of gases. The explosion creates pressure that forces the gases out of the rocket. The reaction force of the gases on the rocket pushes the rocket forward. The force pushing the rocket is called thrust. Explosions in a chamber create pressure that pushes gases out of a rocket.
This in turn produces thrust that pushes the rocket forward. The rocket shown here is a Saturn V rocket, used for the Apollo 11 mission — the first to carry humans to the Moon. For centuries, rockets were powered by gunpowder or other solid fuels and could travel only fairly short distances. At the end of the 19th century and the beginning of the 20th century, several breakthroughs in rocketry led to rockets that were powerful enough to carry the rockets—and humans—beyond Earth. During this period, three people independently came up with similar ideas for improving rocket design.
The first person to establish many of the main ideas of modern rocketry was a Russian schoolteacher, named Konstantin Tsiolkovsky — Most of his work was done before the first airplane flight, which took place in He also realized that it was important to find the right balance between the amount of fuel a rocket uses and how heavy the rocket is.
He came up with the idea of using multiple stages when launching rockets, so that empty fuel containers would drop away to reduce mass. Tsiolkovsky had many great ideas and designed many rockets, but he never built one.
The second great rocket pioneer was an American, Robert Goddard — Goddard independently came up with using liquid fuel and using multiple stages for rockets.
He also designed a system for cooling the gases escaping from a rocket, which made the rocket much more efficient. Goddard built rockets to test his ideas, such as the first rocket to use liquid fuel Figure below. Over a lifetime of research, Goddard came up with many innovations that are still used in rockets today. Which is a sort of success, if you think about it: It's not like our ancestors were able to accomplish such feats as tossing random junk between the stars, but it's probably also not exactly what you imagined interstellar space travel to be like.
To make interstellar spaceflight more reasonable, a probe has to go really fast. On the order of at least one-tenth the speed of light.
At that speed, spacecraft could reach Proxima Centauri in a handful of decades, and send back pictures a few years later, well within a human lifetime. Is it really so unreasonable to ask that the same person who starts the mission gets to finish it?
Going these speeds requires a tremendous amount of energy. One option is to contain that energy onboard the spacecraft as fuel. But if that's the case, the extra fuel adds mass, which makes it even harder to propel it up to those speeds. There are designs and sketches for nuclear-powered spacecraft that try to accomplish just this, but unless we want to start building thousands upon thousands of nuclear bombs just to put inside a rocket, we need to come up with other ideas.
Perhaps one of the most promising ideas is to keep the energy source of the spacecraft fixed and somehow transport that energy to the spacecraft as it travels. One way to do this is with lasers. Radiation is good at transporting energy from one place to another, especially over the vast distances of space.
The spacecraft can then capture this energy and propel itself forward. This is the basic idea behind the Breakthrough Starshot project , which aims to design a spacecraft capable of reaching the nearest stars in a matter of decades.
In the simplest outline of this project, a giant laser on the order of gigawatts shoots at an Earth-orbiting spacecraft. That spacecraft has a large solar sail that is incredibly reflective. The laser bounces off of that sail, giving momentum to the spacecraft. The thing is, a gigawatt laser only has the force of a heavy backpack. You didn't read that incorrectly. If we were to shoot this laser at the spacecraft for about 10 minutes, in order to reach one-tenth the speed of light, the spacecraft can weigh no more than a gram.
This is where the rubber meets the interstellar road when it comes to making spacecraft travel the required speeds. The laser itself, at gigawatts, is more powerful than any laser we've ever designed by many orders of magnitude. To give you a sense of scale, gigawatts is the entire capacity of every single nuclear power plant operating in the United States combined.
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