No alien megastructure around mysterious star

IT has been called the most mysterious star in the universe, bigger than the sun and yet brightening and dimming in an odd way that suggested to some an alien megastructure might be circling it.

But a study out yesterday, compiled by more than 100 scientists who have been observing the star, KIC 8462852, puts the alien rumours to rest.

“Dust is most likely the reason why the star’s light appears to dim and brighten,” lead author Tabetha Boyajian, assistant professor of physics and astronomy at Louisiana State University, for whom Tabby’s Star is nicknamed, said.

“The new data shows that different colours of light are being blocked at different intensities. Therefore, whatever is passing between us and the star is not opaque, as would be expected from a planet or alien megastructure.”

The initial discovery of the star was made with the help of Nasa’s planet-hunting space telescope, known as Kepler.

Kepler detects planets by tracking moments when a star’s light dims as an object passes in front of it. The unusual dips in brightness in Tabby’s Star – more than 1 000 light years away, about 50% bigger and 1 000 degrees hotter than the sun – aroused global interest.

More than 1 700 people donated a total of $100 000 (about R1.2-million) to study it further.

The report is published in The Astrophysical Journal Letters. –