History and future of ion engines

The idea of ion propulsion was invented by and American rocket pioneer Dr. Robert H. Goddard, who explained the theory of this kind of propulsion in 1906. The first experiments with ion thrusters were carried out by Robert Goddard at Clark University from 1916–1917. First working engine for space use, was constructed by team led by Harold Kaufman, an American physicist who worked for NASA, in 1960. First space tests was run in 1964 in specially created probe called SERT-1 (Space Electric Rocket Test). It takes 31 minutes, as it was planned, and successfully ended.


First commercial uses of ion engines were started by Soviets. Since 1972 ion engines were used by them for satellite stabilization. Since then until late 1990s 118 ion thrusters completed their missions. But none of them was used as a main engine.

First satellite with ion thruster as a main engine was American Deep Space 1. It was launched from Cape Canaveral on October 24, 1998. During a highly successful primary mission, it tested 12 advanced, high-risk technologies in space. In an extremely successful extended mission, it encountered Comet Borrelly and returned the best images and other science data ever from a comet.

Deep Space 1 proved that ion technology is stable, fast and economic. After success of the Deep Space 1 mission European Space Agency decided to use this kind of thruster in their satellites. So far it was used by them in 3 missions (Artemis, GOCE and Lisa Pathfinder missions). Also Japanese space agency decided to use ion thruster in their Hayabusa satellite which successfully rendezvoused with the asteroid 25143 Itokawa.


The new ion technology can be also used in Mars exploration. Using traditional rockets, which burn chemical fuel to produce thrust, it will take about six months to reach the Red Planet. To reduce this time in 2005 NASA developed new kind of ion engine called called VASIMR (Variable Specific Impulse Magnetoplasma Rocket). VASIMR can change 6 months journey to 90 days. Scientists thinks that after improvement, it can be reduced even to 39 days. In 2012 NASA is planning first space tests of VASIMR from International Space Station. Maybe it will be a key element for our future Mars exploration.