How to visit Mars with a tiny satellite and static electricity
William Brangham: Finally tonight, a story about a space race that's very close to its finish line.
Tiny satellites known as CubeSats are critical to space exploration.
NewsHour science producer Nsikan Akpan reports how one scientist plans to propel these Rubik's Cube-sized satellites to infinity and beyond.
Nsikan Akpan: Have you heard of space Internet?
Four thousand small satellites orbiting Earth, beaming down high-speed broadband to the most remote nooks of the planet, reaching billions.
SpaceX, Virgin Galactic, Boeing, and Airbus are all racing to make space Internet a reality. This scheme depends on CubeSats, low-cost, bite-sized satellites that many view as the future of telecommunications and deep space exploration.
But these CubeSats have a big problem. Conventional rockets with their huge chemical fuel tanks are too large and too powerful for CubeSats, which are as tiny as Rubik's Cubes or small printers. It'd be like strapping your bicycle to a monster truck.
So CubeSats are currently built without propulsion and can't be controlled once in orbit. This restricts CubeSats to lower orbits, safe from collisions with normal satellites. After a few months, the CubeSats fall back to Earth.
What CubeSats need to stay in space are mini-boosters, and scientists are racing to build them. And if you look inside this chamber, we can show you one capable of blasting them deep into the cosmos.
Paulo Lozano: I grew up in Mexico. And I was very young. I watched Carl Sagan's "Cosmos," as probably every other child in my generation.
Carl Sagan: The cosmos is also within us. We're made of star stuff. We are a way for the cosmos to know itself.
Paulo Lozano: That inspired me to study the stars, to work on things that leave the Earth.
Nsikan Akpan: Paulo Lozano is the director of the Space Propulsion Lab at the Massachusetts Institute Of Technology. He's found a solution to the CubeSat problem, and the idea fueling his mini-rocket is simpler than you might think.
Paulo Lozano: What we can do is to rub the plastic on any fabric, really, and you can put a little bit of liquid on your finger, and then get it close, and you will see the liquid flying, producing a little cone and then flying to the plastic.
Nsikan Akpan: That's static electricity. And it's not just tugging at the droplet. Look more closely, and you will see the static creates a spray of charged molecules called ions.
Lozano's tiny rockets, which are the size of quarters, generate these ion sprays.
Paulo Lozano: They don't produce a lot of force. So it's always less than the weight of a mosquito.
Nsikan Akpan: This may sound wimpy, but even a small action creates a reaction in the frictionless vacuum of outer space. Move ions in one direction, and a CubeSat will move uber-fast in the other.
Paulo Lozano: The best chemical rocket will produce an exhaust of particles that move at about 4,000 meters per second. And an ion engine can go much higher. It can reach 40,00, 50,000, or even more meters a second.
Nsikan Akpan: Up to 111,000 miles per hour, more than enough to stay in orbit around Earth or even blast off to Mars.
Lozano's ion engines look like computer microchips. They contain a grid of 500 needles, each a solar-powered, custom-built nozzle for spewing ions.
Catherine Miller: My name is Catherine Miller. I am a second-year Ph.D. student here. I am also a NASA space technology research fellow.
They're electrochemically etched and chemically roughened to make the needle tip extremely, extremely sharp. And so, from there, you can dip the ionic liquid onto the surface and produce an ion beam that way.
Nsikan Akpan: Latch on a fuel tank the size of a sugar cube, and you're almost ready for liftoff.
Paulo Lozano: What we have in here is relatively big vacuum chamber. You can see what we have right now is a little satellite that is actually magnetically levitated.
We have tiny little thrusters in there that can move the satellite and rotate it around. And we can investigate then how the thrusters behave, how do they affect the motion of the satellite while the vacuum chamber is closed.
Nsikan Akpan: Ion engines aren't new. NASA's Dawn mission, which hopped its way to the asteroid Ceres, would have been impossible without its high-velocity ion engine. But the Dawn mission cost half-a-billion dollars.
Commercial CubeSats can cost as little as $100,000, and this price is dropping. Even children are building CubeSats at their elementary schools. Sure, you're thinking an individual CubeSat can't perform as many operations as a big mission satellite. But there is strength in numbers.
Paulo Lozano: Instead of going to an asteroid every five, 10 years in the traditional way, release a fleet of these tiny little CubeSats and visit 100 asteroids.
Nsikan Akpan: Doing so could prevent Armageddon.
Paulo Lozano: Some of these asteroids, especially the very small ones, they have the potential to collide with the Earth. They won't kill the Earth, but they can kill a city.
Nsikan Akpan: By launching a fleet of CubeSats, scientists could learn the chemical compositions of these city killers. That could be key to destroying. An asteroid made of silicon would be much tougher to stop than one made of iron.
Meanwhile, closer to home, Lozano's ion engines could install CubeSats into shiftable orbits for a space Internet. So, from a truly World Wide Web to stopping asteroids, Lozano's mini-thrusters hope to carry CubeSats to infinity and beyond.
Until next time, I'm Nsikan Akpan, and this is ScienceScope from the PBS NewsHour.
William Brangham: On our Web site, read more about how those tiny satellites could not only teach us more about asteroids and deep space and help avoid Armageddon, but could also help test new technologies that could eventually be used by NASA.
That's at PBS.org/NewsHour.