Two dead stars are dancing around each other proving Einstein's theory right

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Two dead stars are dancing around each other proving Einstein's theory right
Artist’s illustration of Lense-Thirring frame-dragging resulting from a rotating white dwarf in the PSR J1141-6545 binary star systemMark Myers/ARC Centre OzGrav


  • Two dead stars are dancing around each other and dragging space and time along with them.
  • The neutron star is orbiting its white dwarf at nearly a million kilometres per hour and the white dwarf whirls on its axis nearly 30 times an hour.
  • The resulting ‘frame-dragging’ effect proves another aspect of Einstein’s theory of relativity.
A star that’s 1.27 times the mass of the Sun is dragging the fabric of space and time with it. According to Albert Einstein, that’s exactly what happens when the principle of general relativity is at play. He called it the Lense-Thirring ‘frame-dragging’ effect.

A new study published in Science found a pulsar 10,000 to 25,000 light-years from the Sun exhibiting the rare phenomenon. In the Musca constellation, PSR J1141-6545 is creating a cosmic whirlpool around itself as it circles another white dwarf star — which is around the same size as the Sun.

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The resulting pulsar — radio waves emitted along the star’s magnetic poles — orbits the white dwarf at a speed of a million kilometres per hour. It takes less than 5 hours for it to complete one orbit. Even at its furthest, the distance between the two celestial objects is barely larger than the Sun’s diameter.

According to Einstein’s theory of general relativity, there’s a gravitational attraction between masses that results from time and space warping between them. Imagine a ball emerging in a syrup. As the ball moves, the syrup will swirl along with it — just as the star is making space and time rotate.

The dead star tango
A neutron star is the corpse of a star that died in a massive supernova explosion but leftover enough pieces for gravity to pull them together.

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A white dwarf star is the left-over core of a dead star. These stars didn’t die in an explosion, they just ran out of fuel — like the Sun is expected to one day.

The neutron star pulsar, however, is significantly younger than the white dwarf star.

"Systems like PSR J1141-6545, where the pulsar is younger than the white dwarf, are quite rare. It confirms a long-standing hypothesis of how this binary system came to be, something that was proposed over two decades ago," said Venkatraman Krishnan, lead author of the study.

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The scientists were able to observe the drift between the two stars for a period of nearly 20 years using the Parkes and UTMOST radio telescopes in Australia. After eliminating other possible causes for the drift, they concluded that it had to be the result of frame-dragging.

As the white dwarf spins at high speeds, it pulls on the space and time. It whirls on its axis nearly at 30 times an hour. As space and time get dragged, the pulsar’s orbit has slowly changed its orientation over time.

Some experiments have also tried to measure if Earth is privy to the same effect, the effect is so small — that it’s been challenging for scientists to measure. With stars, like white dwarfs and neutron stars, the mass is much larger and gravitational fields are stronger. This makes the frame-dragging effect easier to observe.

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See also:
ISRO, NASA just spotted a black hole spinning so fast that it could be making space itself rotate

A black hole bigger than the sun is pulling on the fabric of space and time
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