Radioisotope rocket: Difference between revisions

[[TRW Inc.|TRW]] maintained a fairly active development program known as '''Poodle''' from 1961 to 1965, and today the systems are still often known as '''Poodle thrusters'''. The name was a play on the larger systems being developed under [[Project Rover]], which led to NERVA. In April 1965 they ran their testbed engine for 65 hours at about 1500 °C, producing a specific impulse of 650 to 700 seconds (6.5 to 7 kN·s/kg).

 

Even without an exhaust, the [[Radiation pressure|photon pressure]] of the energy emitted by a thermal source can produce thrust, although an extremely tiny amount. A famous example of spacecraft thrust due to photon pressure was the [[Pioneer anomaly]], in which photons from the onboard radioisotope source caused a tiny but measurable acceleration of the Pioneer spacecraft.