Hey Science Fans! I’m back from a week off and ready to write so let’s get to it.
You’ll no doubt remember the curious case of Tabby’s Star: a Star about 1300 lightyears away that can very rapidly change its brightness in a way that has, thus far, defied explanation.
Up to 20% of the light from the star has been observed dissipating in just a couple of days, a phenomenon never before seen. Potential explanations for the mysterious goings on have ranged from a planet breaking apart and blocking light to some kind of alien megastructure reminiscent of a Dyson Sphere.
A stellar sized energy harvester was always a bit of a long shot but a new analysis by researchers from Belgium, the US and the UK has further dented such a prospect in favour of the rather more mundane explanation of, erm, Dust. A year of observation in both the infra red and the ultra violet using the Spitzer and Swift space telescopes respectively.
First author, Huan Meng, reports that, “…the amount of dimming is significantly less in the infrared than in the optical and ultraviolet.” This means that whatever is blocking the light from Tabby’s Star is likely to be only a few microns across, not enormous megastructures. Their conclusion: a very large, thin ring of dust is periodically blocking the light.
They do acknowledge that there are problems with this theory, however. The properties of the cloud of dust required to produce the observed dimming effect would have an orbital period of hundreds of thousands or even millions of years; this is difficult to reconcile with the multiple dimming episodes we have seen in the 8 years since the star’s discovery.
Ultimately, though, they argue that, as unusual as this star and the matter obscuring it is, by far the most likely explanation is still that there is just some dust in the way and I, for one, couldn’t disagree.