SoylentNews

takyon writes:

Tabby's Star, speculated to be surrounded by a cloud of debris or alien megastructures, has dimmed yet again, causing multiple observatories to take notice:

Among the telescopes [Jason] Wright said researchers now hope to use to catch this dimming event in the act:

—The Green Bank Telescope in West Virginia, the world's largest fully steerable radio telescope
—The Automated Planet Finder at Lick Observatory near San Jose, Calif., a robotic optical telescope
—Both telescopes at the Keck Observatory in Hawaii, which operate in optical and near-infrared wavelengths
—The MMT Observatory in Arizona, an optical telescope
—NASA's Swift Gamma-Ray Burst Mission, which operates in gamma ray, x-ray, ultraviolet and optical wavelengths
—Las Cumbres Observatory, a worldwide network of robotic optical telescopes
—Fairborn Observatory in Arizona, which operates in optical wavelengths
—The Large Binocular Telescope in Arizona, which operates in optical and near-infrared wavelengths
—The Hobby–Eberly Telescope in Texas, an optical telescope

Also at The Verge.

One astronomer has proposed looking at the nearest 43 to 85 pulsars for megastructures (arXiv):

Osmanov estimates that the habitable zone around a relatively slowly-rotating pulsar (with a period of about half a second) would be on the order of 0.1 AU. According to his calculations, a ring-like megastructure that orbited a pulsar at this distance would emit temperatures on the order of 390 K (116.85 °C; 242.33 °F), which means that the megastructure would be visible in the IR band.

Previously: Mysterious Star May Be Orbited by Alien Megastructures
I'm STILL Not Sayin' Aliens. but This Star is Really Weird.
"Breakthrough Listen" to Search for Alien Radio Transmissions Near Tabby's Star
Non-Alien Explanation for Tabby's Star Dimming: It Ate a Planet

Original Submission

takyon writes:

Tabby's star, aka KIC 8462852, is likely surrounded by orbiting dust grains that block ultraviolet light:

The bizarre long-term dimming of Tabby's star—also known as Boyajian's star, or, more formally, KIC 8462852—is likely caused by dust, not a giant network of solar panels or any other "megastructure" built by advanced aliens, a new study suggests.

Astronomers came to this conclusion after noticing that this dimming was more pronounced in ultraviolet (UV) than infrared light. Any object bigger than a dust grain would cause uniform dimming across all wavelengths, study team members said.

"This pretty much rules out the alien megastructure theory, as that could not explain the wavelength-dependent dimming," lead author Huan Meng of the University of Arizona said in a statement. "We suspect, instead, there is a cloud of dust orbiting the star with a roughly 700-day orbital period."

Aliens left to roam free once again.

Previously: Tabby's Star Under Observation After Dimming Event Detected
Tabby's Star Dimming Could be Explained by a Saturn-Like Exoplanet

Extinction and the Dimming of KIC 8462852 (DOI: 10.3847/1538-4357/aa899c) (DX) (arXiv)

Original Submission