Exploring Space with Tiny Sprite Satellites
Last week I blogged about a planned space mission that would launch a thousand tiny satellites the size of cell phones towards another star propelled by giant lasers. This week, I am going to talk about a proposed satellite launch project that would send even smaller satellites into space.
Mason Peck is an engineer at Cornell University. He just received a seventy five thousand dollar grant from NASA's Institute for Advanced Concepts to study his new magnetic propulsion system which he has been working on since 2005. His satellites are about the size of a dime and very inexpensive. They are integrated circuits that contain everything needed for space missions. Each one centimeter square Sprite contains a battery, a plasma contact capacitor, power conditioning and switching circuitry, a "science lab on a Sprite", a radio, a high efficiency solar cell array and thrusters. In 2011, several prototype Sprites were sent to the International Space Station to test the ability of the Sprites to withstand conditions in space.
Instead of requiring fuel to escape Earth orbit and explore the solar system, Mason's satellites, called Sprites, would use the Lorentz force which acts on charged particles moving in a magnetic field to propel them to other planets.
The idea of very tiny satellites has been around for twenty years. It evolved from the idea of "smart dust" which is a name for tiny micoelectromechanical sensors that could be distributed into the environment to measure light, temperature, movement, chemicals and biological substances. Eventually it was realized that these tiny sensors could be incorporated into satellites and sent into space. Research on such tiny satellites has been carried out by Surrey Space Centre, the University of Strathclyde, the Aerospace Corp., and the Jet Propulsion Laboratory.
Millions of these satellites could be launched into space and form vast sensor networks across millions of miles. Each satellite could provide a simple measurement. Taken together, the aggregate measurements of such satellites could reveal important information about conditions in space.
Mason hopes to send his Sprites to Europa, a moon of Jupiter, by 2030. Thousands of Sprites would be packed into the nose of a rocket and then launched into Earth orbit. Each Sprite trails a long wire attached to a capacitor. A solar panel on the Sprite would send electrons to the capacitor and they would flow through the attached wire. The Lorentz force would exert a force on the charged Sprite causing it to gain altitude. After a year, the Lorentz force would have pushed the Sprite free of the Earth's gravitation. With the correct timing, the Sprites would then fly away from Earth on a trajectory that would take them to Europa. Following a journey of several years, tiny thrusters on the Sprites could adjust their flight to insure that most of them reach Europa. Because they are so small, they would not burn up as they descend through the European atmosphere. The atmosphere would be sampled by the Sprites for molecules that indicate the existence of life. Any Sprite that detected organic molecules would send a simple one bit message back to Earth.
Early artist's concept of a Sprite satellite:
James Provost