Now Einstein and his theory of general relativity predict that such orbits ought to display effects of gravitational waves, in that, as the stars very gradually close in on one another they end up orbiting each other increasingly faster.
The death of stars is as inescapable a fact of life as is that of all living things, stars burning, in time, right through all of their nuclear fuel and coming to an inevitable end, yet two burnt-out white dwarf stars are enabling astrophysicists the opportunity to indirectly observe to gravitational waves. These are in fact very – faint ripples in space-time fabric which affect surrounding space in much the same way as a pebble thrown into a pond affects the water.
Einstein’s general theory of relativity, in 1916, predicted the existence of these so-called gravitational waves, which are by their very nature extremely weak quick to disappear, though scientists did, in Nobel Prize winning 1993 work, find indirect evidence of their existence in the radio wave regime observations of a binary pulsar. What these boffins dubbed their gravitational wave detector was in fact the newly upgraded LIGO – Laser Interferometer Gravitational Observatory, a device that since 2002 has been searching space for gravity waves, in a joint project of MIT, Caltech, and many other bodies.
The scrapping of some space project funding meant that the planned, NASA gravitational wave detector, dubbed LISA – Laser Interferometer Space Antenna – as well as well as the European Space Agency scaled-down New Gravitational Wave Observatory both got scrapped, bur researchers were fortunate enough to discover the binary system last April. It transpires that the two stars are so close together that they make full orbits in less than 13 minutes.
It appears that astronomers have now managed to obtain more indirect evidence of gravitational waves emitting from this pair of dead white dwarf stars., in the optical regime.
They could only confirm this with the aid of a very accurate celestial clock,which the stars themselves provided – it turns out that, viewed from Earth, the pair eclipse each other every six minutes without fail, so that the general relativistic effects can in fact be easily measured – so much so that based on over 200 hours of observational data that was over time collected by several terrestrial telescopes world-wide, the two stars are indeed eclipsing one another 6 seconds quicker now than they did 12 months ago, showing that,, just as general relativity predicts, gravitational waves have to be a reality.
Much more concrete evidence is needed of course, but it is a step on the road to understanding gravity, and that could, conceivably, hold the secret to the future of interstellar space travel, which is the most cherished of human ambitions, to boldly go etc.