Alien Megastructures: Strange Star Likely Swarmed by Comets (+Video)

An oddly dimming star located 1,500 light-years from Earth is causing all sorts of commotion in the scientific community, leading some to speculate that it may be some sort of alien megastructure. A new analysis of infrared data suggests a more natural explanation.

To quickly recap, star KIC 8462852, also known as “Tabby’s Star,” is exhibiting unprecedented flickering behavior. Normally, astronomers observe dips in brightness when a planet temporarily passes in front of a star. This dimming tends to be slight (just a few percentage points, even for gas giants like Jupiter) and periodic (which is suggestive of a planet in a stable orbit). But Tabby’s Star is different. Very different. At times, its brightness drops by a whopping 22%! What’s more, its brightness changes irregularly, sometimes for days—sometimes for months. Scientists have never observed anything quite like this, leading to all sorts of wild speculation.

For instance, the aperiodic dimming could be the product of a catastrophic collision in the star’s asteroid belt, or the result of a giant impact that disrupted a nearby planet. Alternately, it might just be a dusty cloud of rock and debris. There’s even the possibility that it’s a distorted star. And as Penn State astronomer Jason Wright and colleagues speculated, it might be an alien megastructure, like a Dyson sphere, though as Oxford’s Anders Sandberg points out, that’s bloody unlikely.

In an attempt to learn more about Tabby’s Star, Iowa State University astronomer Massimo Marengo and his team analyzed data acquired by the Infrared Array Camera aboard NASA’s Spitzer Space Telescope. As they conclude in their ensuing paper, which now appears at The Astrophysical Journal, the destruction of a family of comets near the star is the most likely explanation for the mysterious dimming.

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http://gizmodo.com/that-supposed-alien-megastructure-may-actually-be-a-swa-1744792437

Strange Star Likely Swarmed by Comets  http://www.nasa.gov/feature/jpl/strange-star-likely-swarmed-by-comets

This illustration shows a star behind a shattered comet. Observations of the star KIC 8462852 by NASA’s Kepler and Spitzer space telescopes suggest that its unusual light signals are likely from dusty comet fragments, which blocked the light of the star as they passed in front of it in 2011 and 2013. The comets are thought to be traveling around the star in a very long, eccentric orbit.
Credits: NASA/JPL-Caltech