RE: Albert Einstein - the Universe and Physics #9
This article made me remember a famous incident from 2014, when two satellites were launched by the european space agency (Galileo satellites 5 and 6) and were intended to be sent into a circular orbit at 23000 km above the earth.
Due to a thermal breach between the line of liquid helium and the line of propellant (which caused the propellant to froze), the altitude correction thrusters stopped working.
The satellites were sent into a random direction which ended up in a elliptical orbit, varying from 17000 to 26000 km of altitude. This "mistake" had a huge advantage in measuring the effect of gravitational potential on time because, being the same atomic clock that made the measurement on both altitudes, it helped to identify and eliminate most of the errors.