APOD: Unexplained Dimmings in KIC 8462852 (2016 Jun 13)

[APOD Robot]

Unexplained Dimmings in KIC 8462852

Explanation: Why does star KIC 8462852 keep wavering? Nobody knows. A star somewhat similar to our Sun, KIC 8462852 was one of many distant stars being monitored by NASA's robotic Kepler satellite to see if it had planets. Citizen scientists voluntarily co-inspecting the data along with computers found this unusual case where a star's brightness dropped at unexpected times by as much as 20 percent for as long as months -- but then recovered. Common reasons for dimming -- such as eclipses by orbiting planets or stellar companions -- don't match the non-repetitive nature of the dimmings. A currently debated theory is dimming by a cloud of comets or the remnants of a shattered planet, but these would not explain data indicating that the star itself has become slightly dimmer over the past 125 years. Nevertheless, featured here is an artist's illustration of a planet breaking up, drawn to depict NGC 2547-ID8, a different system that shows infrared evidence of such a collision. Recent observations of KIC 8462852 did not detect the infrared glow of a closely orbiting dust disk, but gave a hint that the system might have such a disk farther out. Future observations are encouraged and creative origin speculations are sure to continue.

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[bystander]

http://asterisk.apod.com/viewtopic.php?t=33829
http://asterisk.apod.com/viewtopic.php?t=35401

[emc]

Perhaps we should stop using the phrase "Earth shattering news"... you know... so we don't thru some collective human mental power, draw a calamity upon ourselves. Else we will puzzle some distant intelligent race of our sun's mysterious periodic dimming.

[Fred the Cat]

Great way start to the week! When a "sober scientist" decides to acronym her paper with "WTF" it activates my already overstimulated imagination to a manic proportion.

The other methods of exoplanet detection do add clarity but I'm sure many will be brainstorming this for a while and perhaps holography will sharpen the images

[JohnD]

I really don't think that a planet that had suffered some cataclysmic collision would look like a breakfast egg with the top off.
Surely with it so molten inside as to appear all yolk, it would have very quickly reformed into a globe?

And oblique impacts produce bilateral debris plumes, not in line with the impactor's trajectory

These "artists impressions" should at least conform to physics.
John

[JL65]

Just a thought - could an orbital body with a "tilted" orbit (out of the planetary disk plane, for example) colliding with another orbital body close to the plane produce both a somewhat cohesive debris field on a non-standard or erratic orbit, as well as a generalized debris cloud within the plane that could explain the odd dimming events as well as general dimming of the host star over the last century?

[Chris Peterson]

I really don't think that a planet that had suffered some cataclysmic collision would look like a breakfast egg with the top off.
Surely with it so molten inside as to appear all yolk, it would have very quickly reformed into a globe?

Even if it were solid it would reform into a sphere very rapidly. Any body that isn't made of some hypothetical exotic type of matter will collapse to a near sphere (hydrostatic equilibrium) once its diameter exceeds a few hundred kilometers (perhaps as much as 1000 km or so for oddly spinning bodies).

[geckzilla]

One of the less apparent physical failings of the image are the shadows cast by the little planetoids and whatnot scattered in the background fog. It's something depicted very commonly in space imagery, but I have strong doubts that it ever actually happens.

[JohnD]

Yes, geck, the space around them would need to be very dusty, just like sunbeams on Earth that only appear when they illuminate airbourne dust.
John

[Chris Peterson]

One of the less apparent physical failings of the image are the shadows cast by the little planetoids and whatnot scattered in the background fog. It's something depicted very commonly in space imagery, but I have strong doubts that it ever actually happens.

Agreed. Even the presolar nebula was probably not so visibly dusty (the mass of dust in that volume would be absurdly huge). And in any case, by the time you have actual planets most of the dust has been swept from the system.

[Boomer12k]

Maybe it is a combination of things....

Can't wait to find out.

Reminds me of the Yu-gi-oh game card... Mirror Force... the way it is splayed out...

:---[===] *

[Gail]

Never mind all the reasoned replies to this artist's image; this visual of a planet missing its upper half and being obviously nearly molten filled me with the most awful dread. What a dramatic, gut-wrenching rendering of the most terrible thing I can imagine, of course projecting it to happen to Earth. Nightmares tonight.

[BMAONE23]

If you turn the image 90 deg you get to view one of the ancient astronauts

[JohnD]

Gail,
please read the posts above - this picture is in the same class as imaginative fiction (perhaps Game of Stones?) or at worst is of this solar system at a much earlier time. The likelihood of an event on this scale is extremely remote, so remote that the Earth will probably end as it is absorbed into the expanding Sun as that moves towards the end of its life and becomes a Red Giant star. In about 4 billion years time.

John

[Trent Franklin]

What if light spectrums actually have slightly different speeds?

[Fred the Cat]

What if light spectrums actually have slightly different speeds?

In trying to explore the answers to many questions we have great tools right at our fingertips. That often points one in a direction not always expected but usually enlightening.