“The Kepler Dimming-Star Mystery” –‘Alien Megastructure’ Buzz Could Soon Be Put to Rest

 

 

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The internet has been abuzz this week over the possibility of intelligent alien life somewhere in our galaxy. An article published by The Atlantic set off the storm. The story details how NASA’s planet-hunting Kepler spacecraft has spotted an odd star in the Milky Way named KIC 8462852.


The world’s astronomy community is keeping a close eye on the strange star, discovered last year by Tabetha Boyajian, a postdoctoral fellow at Yale University, which has dimmed dramatically numerous times over the past few years, dropping in brightness by up to 22 percent. These events have triggered a viral global conversation that the star may be surrounded by some type of alien megastructure, a Dyson-sphere type object— a hypothesis that will be put to the test if and when KIC 8462852 dims again, according to Jason Wright, an astronomer at Pennsylvania State University.

“As long as one of those events occurs again, we should be able to catch it in the act, and then we’ll definitely be able to figure out what we’re seeing,” Wright told Space.com. Last year, Wright met Boyajian at a talk she gave at the Center for Exoplanets and Habitable Worlds. After the seminar she spoke to Wright and showed him a star spotted from the Kepler telescope by her and her team. “The search for extraterrestrial intelligence doesn’t have many good targets to look at, so this seems like the best one,” Wright said.

The headlines are completely ridiculous and misleading, according to MIT astronomer and planetary scientist, Sara Seager. “It’s just irresponsible reporting. Because if you take a look at the paper — the scientific paper the authors wrote — [that idea] is not really even in there,” Seager, told The Verge.

“I was fascinated by how crazy it looked,” Wright told The Atlantic. “Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilization to build.”

According a fascinating report in Gizmodo, some astronomers are saying it might just be caused by gravity darkening and spin-orbit misalignment of a rapidly spinning and irregularly shaped star. 

The Independent, a British news organization, reported that the star is above the Milky Way and lies in between the constellations Cygnus and Lyra. This star is different because it has debris surrounding the star giving off strange light curves, Wright said. “My best guess is that somehow it’s a disk of material around the star,” Wright said. “But the best theory going around now is that it’s an enormous swarm of comets.”

Young stars usually have disks that form from protoplanetary disks. As the star ages, these disks break off and form planets. However, there are no signs that show this is a young star, Wright said.

Young stars have a disk very close to the star, so there is a lot of heat coming off of it. They do not move very fast through the galaxy, and they usually are accompanied by other stars that formed with it that are moving in the same direction, Wright said. KIC8462852 has none of these features.

Wright also said that from a natural science perspective, there is no reason to think aliens are the best explanation.

Fifty years ago the Princeton Institute for Advanced Study physicist, Freeman Dyson, speculated that vast structures could ring or completely enclose their parent star. These Dyson Spheres, the work of a Kardashev Type II civilization — would be capable of drawing on the entire energy output of its star.

Atsoniomers are studying Kepler systems for telltale evidence of such structures by examining changes in light levels around the parent star as well as possible laser traffic among extraterrestrial civilizations. “Fermi Bubbles,” which might appear as a void in visible light in spiral galaxies, is the term used by Richard Carrigan, a scientist emeritus at Fermilab, in his work on the search for cosmic-scale artifacts like Dyson spheres or Kardashev civilizations using Infrared Astronomical Satellite (IRAS) data . A Fermi bubble would grow as the civilization creating it colonized space, according to Carrigan.

A civilization, believes Carrigan, could engulf its galaxy on a time scale comparable to the rotation period of the galaxy, or every 225–250 million years, and perhaps shorter.

Searching for signatures of cosmic-scale archaeological artifacts such as Dyson spheres or Kardashev civilizations is an interesting alternative to conventional SETI. Uncovering such an artifact does not require the intentional transmission of a signal on the part of the original civilization.

The Daily Galaxy via Penn State University, Space.com, and The Verge.

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