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Spacecraft to prove Einstein’s theory of general relativity

Three spacecraft orbiting the Sun and 3 million miles apart are to fire lazer beams at each other across the emptiness of space in order to finally prove whether Einstein’s theory of general relativity is true or not.

The physicists running the mission – which is a joint venture between NASA and the ESA – hope that in doing so they will be able to prove or disprove the existence of gravitational waves, a phenomenon predicted in Einstein’s famous theory.

The lazer beams will be fired between the spacecraft, each of which is carrying floating cubes of gold platinum, to measure minute changes in the distance between each of the cubes. These differences are postulated to be caused by the weak waves of gravity that ripple out from catastrophic events in deep space, such as the collapse of stars.

It is these waves that will hold the key to proving or debunking the theory, as Einstein predicted that when large objects such as black holes collide, ripples in space and time flow outwards forming gravitational waves.

Professor Jim Hough, an expert on gravitational waves at Glasgow University, said:

“Gravitational waves are the last piece of Einstein’s theory of general relativity that has still to be proved correct. They are produced when massive objects like black holes or collapsed stars accelerate through space.

“Unfortunately we haven’t been able to detect them yet because they are very weak. However, the new experiments we are working on have great potential to allow detection.”




  • Matt McNair

    Light amplification by stimulated emission of radiation.
    No z.

  • Graham Beckett

    would have been good to see a diagram showing spacecraft in relation to sun.As they are only 3 million miles apart they could not be 120 degrees apart in an orbit around the sun as they would be inside the orbit of mercury (very hot)! any more info?