Tabby’s Star is getting lots of attention, even SETI is getting in the game. But to get an idea of what more mundane explanations are making the rounds, there are two good papers out, and one posits a giant and no doubt very warm—possibly still roiling giant dusty gas-ball after a recent monster collision—with huge cold rings and two sets of very cold Trojans as seen in the image above:
The first is by Ballesteros et al. (MNRAS, submitted) and they try to model the dips with a gigantic planet with a huge ring system and huge swarms of trojan asteroids. In other words, their model puts a lot of stuff in a 6 au orbit around the star, which is far enough away that it would be pretty cold. They point out that the deep, asymmetric dip at Kepler day 793 occurs about half way in the middle of a pretty quiescent period for Tabby’s Star. They associate the other dips with swarms of trojan asteroids—asteroids in the same orbit as the planet but leading or trailing the planet by 60 degrees.
That does explain some things fairly well. It’s likely that something like this will eventually turn out to work. And the low odds of such an odd combination existing, and being oriented in such a way as to lie right between the star and our perspective, helps explain why we haven’t seen other stars behave this way. But it doesn’t explain everything perfectly. Maybe we’ll have a full article on that soon, if and when we know more.
- Is there anything chocolate can’t do?
- Don’t you know the sea level’s going up, up, Up, UP! (To live in those towns, you’ll have to be tough tough tough tough!)
- Star Wars was released 40 years ago this very weekend. And the Bad Astronomer, apparently with some excess time on his hands, reviews the film and its chief evilness: The Death Star!
- New research suggests whales reached dirigible size only in the relatively recent geological past and the reason may be related to a cooler climate beginning about three million years ago favoring the evolution of giant baleen whales:
Ice sheets in the north develop a lot of cold water that sinks and is then transported around the globe. And what you get are intense upwellings that bring that nutrient-rich cold water back to the surface. That allows algae to go crazy and that allows krill to feed and to form really dense aggregations.
from Daily Kos http://ift.tt/2r0bt7j
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