Post by swamprat on Apr 1, 2012 8:42:36 GMT -6
ScienceDaily
Getting to the Moon On Drops of Fuel
ScienceDaily (Mar. 29, 2012) — Imagine reaching the Moon using just a fraction of a liter of fuel. With their ionic motor, MicroThrust, EPFL scientists and their European partners are making this a reality and ushering in a new era of low-cost space exploration. The complete thruster weighs just a few hundred grams and is specifically designed to propel small (1-100 kg) satellites, which it enables to change orbit around Earth and even voyage to more distant destinations -- functions typically possible only for large, expensive spacecraft. The just-released prototype is to be employed on CleanSpace One, a satellite under development at EPFL that is designed to clean up space debris, and on OLFAR, a swarm of Dutch nanosatellites that will record ultra-low radio-frequency signals on the far side of the Moon.
Small satellites are all the rage right now because their manufacturing and launch costs are relatively low -- about half a million dollars, compared to conventional satellites that run into the hundreds of millions. But nanosatellites currently lack an efficient propulsion system that would render them truly autonomous and thus able to carry out exploration or observation missions.
A motor that doesn't burn fuel
Instead of a combustible fuel, the new mini motor runs on an "ionic" liquid, in this case the chemical compound EMI-BF4, which is used as a solvent and an electrolyte. It is composed of electrically charged molecules (like ordinary table salt) called ions, except that this compound is liquid at room temperature. The ions are extracted from the liquid and then ejected by means of an electric field to generate thrust. This is the principle behind the ionic motor: fuel is not burned, it is expelled.
Cruising speed: 40,000 km per hour
After six months of acceleration, the microsatellite's speed increases from 24,000 km/h, its launch speed, to 42,000 km/h. The acceleration is only about a tenth of a millimeter per square second, which translates into 0-100 km/h in 77 hours. But in space, where there is no friction to impede motion, gentle but steady acceleration is the way to go.
The ionic motor will power CleanSpace One -- a nanosatellite whose mission is to tidy up space by grabbing space debris and pulling it into Earth's atmosphere to be safely incinerated. According to the Swiss Space Center, CleanSpace One will take two to three months and more than 1,000 terrestrial revolutions to reach one of its targets, the decommissioned Swisscube cubesat or Tlsat-1 cubesat. Scientists have just over a year to finalize their system.
Read more: www.sciencedaily.com/releases/2012/03/120329101802.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fmatter_energy+%28ScienceDaily%3A+Matter+%26+Energy+News%29
Getting to the Moon On Drops of Fuel
ScienceDaily (Mar. 29, 2012) — Imagine reaching the Moon using just a fraction of a liter of fuel. With their ionic motor, MicroThrust, EPFL scientists and their European partners are making this a reality and ushering in a new era of low-cost space exploration. The complete thruster weighs just a few hundred grams and is specifically designed to propel small (1-100 kg) satellites, which it enables to change orbit around Earth and even voyage to more distant destinations -- functions typically possible only for large, expensive spacecraft. The just-released prototype is to be employed on CleanSpace One, a satellite under development at EPFL that is designed to clean up space debris, and on OLFAR, a swarm of Dutch nanosatellites that will record ultra-low radio-frequency signals on the far side of the Moon.
Small satellites are all the rage right now because their manufacturing and launch costs are relatively low -- about half a million dollars, compared to conventional satellites that run into the hundreds of millions. But nanosatellites currently lack an efficient propulsion system that would render them truly autonomous and thus able to carry out exploration or observation missions.
A motor that doesn't burn fuel
Instead of a combustible fuel, the new mini motor runs on an "ionic" liquid, in this case the chemical compound EMI-BF4, which is used as a solvent and an electrolyte. It is composed of electrically charged molecules (like ordinary table salt) called ions, except that this compound is liquid at room temperature. The ions are extracted from the liquid and then ejected by means of an electric field to generate thrust. This is the principle behind the ionic motor: fuel is not burned, it is expelled.
Cruising speed: 40,000 km per hour
After six months of acceleration, the microsatellite's speed increases from 24,000 km/h, its launch speed, to 42,000 km/h. The acceleration is only about a tenth of a millimeter per square second, which translates into 0-100 km/h in 77 hours. But in space, where there is no friction to impede motion, gentle but steady acceleration is the way to go.
The ionic motor will power CleanSpace One -- a nanosatellite whose mission is to tidy up space by grabbing space debris and pulling it into Earth's atmosphere to be safely incinerated. According to the Swiss Space Center, CleanSpace One will take two to three months and more than 1,000 terrestrial revolutions to reach one of its targets, the decommissioned Swisscube cubesat or Tlsat-1 cubesat. Scientists have just over a year to finalize their system.
Read more: www.sciencedaily.com/releases/2012/03/120329101802.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fmatter_energy+%28ScienceDaily%3A+Matter+%26+Energy+News%29