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Massive Exoplanet Discovered, Challenges Established Planet Formation Theories
sfcrazy writes "A giant exoplanet that is in the most distant orbit ever seen around its host star, has been recently discovered. Dubbed HD 106906 b, the newly discovered planet is relatively young (13 million years old, compare this to our 4.5 billion years old Earth) and bigger than any other planet discovered till date. It is 11 times the size of Jupiter, and that's what makes it a most singular discovery."
How do astronomers calculate the age of a distant planet? I can see how they'd get distance from host star (orbital period) and mass (displacement of host star) but how on earth do you work out the age?
foo mane padme hum
By counting the rings, obviously ;)
which is totally what she said
http://www.scientificamerican.com/article.cfm?id=how-do-scientists-determi
Harrison's Postulate - "For every action there is an equal and opposite criticism"
that's 8% the size of the son
Or 0.003% the size of yo momma.
Well, mass and size get thrown around a lot semi-interchangeably which they're most definitely not.
80x the MASS of Jupiter and something becomes a star, but the established theory IIRC was that until you get to that point you keep cramming things in and the planet itself just kinda compresses more and doesn't get much bigger than Jupiter. If it ever gets big enough to become a star and achieve fusion then the pressure pushes it out and then it gets better.
So if it is as the summary says and the planet is literally 11 times the size of Jupiter then that's quite a find. It basically says that there's either something wrong with either a) our understanding of planet formation or b) there's something wrong with how we measured this and the data is just wrong.
If its 11 times the mass then yeah - kind of boring and expected.
"People who think they know everything are very annoying to those of us who do."-Mark Twain
If it's 11 times the diameter, then gravity would be pretty tame at the surface unless it's extremely dense. For example, Jupiter's diameter is 11.2 times that of Earth, but the surface gravity is only 2.64 times that of Earth. Saturn and Uranus both have equatorial surface gravities roughly equal to Venus, in spite of being 9.44 and 4 Earth diameters, respectively.
Source: http://www.windows2universe.org/our_solar_system/planets_table.html
Nice article, but that only says how they get the age of a star. I suppose that puts an upper limit on the age of the planet.
foo mane padme hum
OK I answered my own question with some googling.
http://www.universetoday.com/76495/the-hunt-for-young-exoplanets/
foo mane padme hum
I work at Facebook. You do NOT see the date of which a person was born with said birthday notifications. I suggest you go home and do your homework.
What's more distressing is that you, a Facebook employee, know that he's not at home. Dun dun dunnnn....
That's the mass threshold for deuterium fusion. No fusion = planet, deuterium fusion = brown dwarf, hydrogen fusion = main sequence star.
So at 11 Jovian masses, the planet is close, but not quite big enough to reach brown dwarf status.
The headline as submitted isn't really correct. The planet is not the biggest found; there are several whose mass may be larger, like the exoplanets announced just last week (and this planet has 11 times the mass of Jupiter; we don't know its actual size). The real issue with HD 106906 b is that it is so far out from its parent star, much farther out than planets with that ass should form. Either it formed farther in and got tossed out (which is unlikely) or it formed where it was, which current theories say is difficult; usually objects forming that far out have much higher mass. I explain all this in my own blog post about it.
*** Phil Plait, aka The Bad Astronomer http://www.badastronomy.com