The Alien Megastructure Around Mysterious 'Tabby's Star' Is Probably Just Dust, Analysis Shows (theguardian.com)

An analysis by more than 200 astronomers has been published that shows the mysterious dimming of star KIC 8462852 -- nicknamed Tabby's star -- is not being produced by an alien megastructure. "The evidence points most strongly to a giant cloud of dust occasionally obscuring the star," reports The Guardian. From the report: KIC 8462852 is approximately 1,500 light years away from the Earth and hit the headlines in October 2015 when data from Nasa's Kepler space telescope showed that it was dimming by unexplainably large amounts. The star's light dropped by 20% first and then 15% making it unique. Even a large planet passing in front of the star would have blocked only about 1% of the light. For an object to block 15-20%, it would have to be approaching half the diameter of the star itself. With this realization, a few astronomers began whispering that such a signal would be the kind expected from a gigantic extraterrestrial construction orbiting in front of the star -- and the idea of the alien megastructure was born.

In the case of Tabby's star, the new observations show that it dims more at blue wavelengths than red. Thus, its light is passing through a dust cloud, not being blocked by an alien megastructure in orbit around the star. The new analysis of KIC 8462852 showing these results is to be published in The Astrophysical Journal Letters. It reinforces the conclusions reached by Huan Meng, University of Arizona, Tucson, and collaborators in October 2017. They monitored the star at multiple wavelengths using Nasa's Spitzer and Swift missions, and the Belgian AstroLAB IRIS observatory. These results were published in The Astrophysical Journal.

Comments

Maybe...

[Zaatxe]

... the alien megastructure was destroyed in an interplanetary war and now it's all debris! I want to believe!!!

Re:Maybe...

[Man On Pink Corner]

Or, the structure is designed to capture more energetic radiation at the expense of IR.

It's always amusing to read authoritative declarations from eminent scientists regarding how a Kardashev Type-II civilization might or might not take care of business.

Re:Maybe...

[K. S. Kyosuke]

You don't need to even guess; just consider Earth's potential energy. You need about 60 megajoules per kilogram to remove said kilogram of mass from the surface to infinity. Even a megaton nuke only has enough energy to remove less than a megaton of material from Earth. Consequently, we can't even lift a smallish mountain with all the nukes we have.

Re:Maybe...

[bruce_the_loon]

Nope, not by many orders of magnitude. Estimates of current nuclear weapon stockpiles range from 1500 to 6600 megatons TNT equivalent. The Chicxulub impactor is estimated at 100000 megatons and all that did was drill a hole 180km across and 20km deep and possibly triggered vulcanism on the other side of the planet. It didn't shatter the planet.

The impactor in the event 3.26 billion years back was a rock between 37km and 58km and that didn't fracture the planet into pieces either.

If we put all the nukes in a hole 10km down and set them off at once, I doubt we'd even get surface displacement beyond seismic shaking for a couple of seconds.

Re:Maybe...

[admin7087]

This is really interesting. Could someone in-the-know provide a rough calculation ... how many nukes do we need to blow up earth into tiny fragments? And how do they need to be positioned?

I'm asking for a friend.

Re:Maybe...

[K. S. Kyosuke]

I had to find out what it means, because I didn't know the word:

A supercargo (from Spanish sobrecargo) is a person employed on board a vessel by the owner of cargo carried on the ship. The duties of a supercargo are defined by admiralty law and include managing the cargo owner's trade, selling the merchandise in ports to which the vessel is sailing, buying and receiving goods to be carried on the return voyage, and ending all or almost all life on the planet.

Blue

[lessthan]

Or maybe they really like the color blue? Perhaps we've found the home system of the Blue Man Group, where they have a blue house with a blue window. Blue is the color of all that they wear. Blue are the streets and all the trees are too. They have a girlfriend and she is so blue. Blue are the people there that walk around. Blue like their Corvette, it's in and outside. Blue are the words they say and what they think. Blue are the feelings that live inside them.