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Post Info TOPIC: KIC 8462852
Blobrana


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RE: KIC 8462852
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Title: KIC 8462852: Will the Trojans return in 2021?
Author: Fernando J. Ballesteros, Pablo Arnalte-Mur, Alberto Fernandez-Soto, Vicent J. Martinez

KIC 8462852 stood out among more than 100,000 stars in the Kepler catalogue because of the strange features of its light curve: a wide and asymmetric dimming taking up to 15 per cent of the total light, together with a period of multiple, narrow dimmings happening approximately 700 days later. Several models have been proposed to account for this abnormal behaviour, most of which require either unlikely causes or a finely-tuned timing. We aim at offering a relatively natural solution, invoking only phenomena that have been previously observed, although perhaps in larger or more massive versions. We model the system using a large, ringed body whose transit produces the first dimming and a swarm of Trojan objects sharing its orbit that causes the second period of multiple dimmings. The resulting orbital period is T \approx 12 years, with a semi-major axis a \approx 6 au. In this context the recent observation of a minor dimming can be explained as a secondary eclipse produced by the passage of the planet behind the star. Our model allows us to make two straightforward predictions: we expect the passage of a new swarm of Trojans in front of the star starting during the early months of 2021, and a new transit of the main object during the first half of 2023.

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Blobrana


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Tabetha's Star
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Title: Tabetha's Rings
Author: J. I. Katz

Could the dips of "Tabetha's Star" (KIC 8462852) have been caused by matter in our Solar System? The interval between periods of deep dips is nearly twice the orbital period of the Kepler satellite. I consider a clumpy particulate ring in the outer Solar System that grazes the line of sight to the star once per orbit of Kepler. The hypothesis predicts that future dips may be observed from Earth during windows separated by a year, although their detailed structure depends on the distribution of particles along the ring. Dips observed at separated sites will be decorrelated, with correlation lengths \lesssim 10^12 cm, and possibly as short as ~600 m.

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Blobrana


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Boyajian's Star
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ATel 10405: A Drop in Optical Flux from Boyajian's Star



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Blobrana


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RE: KIC 8462852
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Astronomers scramble as 'alien megastructure' star dims again

The most famously weird star in our galaxy is acting up again. On Friday, 19 May, Tabbys star began to dim, carrying on a history of mysterious dips in brightness. Astronomers are scrambling to point as many telescopes as possible at the star, which is 1,300 light-years away in the constellation Cygnus, to decipher its strange signal.
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Blobrana


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TYC 3162-665-1
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Title: Mysterious eclipses in the light-curve of KIC8462852: a possible explanation
Author: L. Neslusan J. Budaj

Apart from thousands of 'regular' exoplanet candidates, Kepler satellite has discovered a few stars exhibiting peculiar eclipse-like events. They are most probably caused by disintegrating bodies transiting in front of the star. However, the nature of the bodies and obscuration events, such as those observed in KIC8462852, remain mysterious. Swarm of comets or artificial alien mega-structures have been proposed as an explanation for the latter object.
We explore the possibility that such eclipses are caused by the dust clouds associated with massive parent bodies orbiting the host star.
We assume a massive object and a simple model of the dust cloud surrounding the object. Then, we use the numerical integration to simulate the evolution of the cloud, its parent body, and resulting light-curves as they orbit and transit the star. It is found that it is possible to reproduce the basic features in the light-curve of KIC8462852 with only four objects enshrouded in dust clouds. The fact that they are all on similar orbits and that such models require only a handful of free parameters provide additional support for this hypothesis.
This model provides an alternative to the comet scenario. With such physical models at hand, at present, there is no need to invoke alien mega-structures into the explanation of these light-curves.

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Blobrana


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Tabby's Star
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Dish to listen for ET around strange star

A $100m initiative to listen for signals from alien life is targeting a star with an unusual dimming pattern.
The Breakthrough Initiative, backed by Prof Stephen Hawking and Facebook's Mark Zuckerberg, will train a US radio telescope on a target called Tabby's Star. Tabby's Star has been a subject of attention and controversy over its irregular dimming pattern.
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Blobrana


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RE: KIC 8462852
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Something 20 times Jupiter's size may be orbiting a nearby star

The two dimming events she observed from KIC 8462852 happened around the 800th and 1,500th days of observation, when the star's light dropped by 15 and 22 percent, respectively. A planet the size of Jupiter, roughly 11 times the size of Earth, would cause a dip of only 1 percent - so whatever is orbiting KIC 8462852 is much bigger than the largest planet in our solar system.
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Title: KIC 8462852 - The Infrared Flux
Author: Massimo Marengo, Alan Hulsebus, Sarah Willis

We analysed the warm Spitzer/IRAC data of KIC 8462852. We found no evidence of infrared excess at 3.6 micron and a small excess of 0.43 ±0.18 mJy at 4.5 micron, below the 3 sigma threshold necessary to claim a detection. The lack of strong infrared excess 2 years after the events responsible for the unusual light curve observed by Kepler, further disfavours the scenarios involving a catastrophic collision in a KIC 8462852 asteroid belt, a giant impact disrupting a planet in the system or a population of a dust-enshrouded planetesimals. The scenario invoking the fragmentation of a family of comets on a highly elliptical orbit is instead consistent with the lack of strong infrared excess found by our analysis.

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Blobrana


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KIC 8462852: Strange Star Likely Swarmed by Comets

A star called KIC 8462852 has been in the news recently for unexplained and bizarre behavior. NASA's Kepler mission had monitored the star for four years, observing two unusual incidents, in 2011 and 2013, when the star's light dimmed in dramatic, never-before-seen ways. Something had passed in front of the star and blocked its light, but what?
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Have astronomers discovered an alien megastructure?

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