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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
Guesswork. They take what they think they know and use it to make a guess that will change every time they find out what they thought they knew was wrong. It's fun to follow but don't put too much faith in it.
They got a birthday notification from the planet's Facebook page.
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.
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?
They can't accurately predict it to a degree of 100% certainty. However they can guess based on it's radiation level and it's decay of said rad signal. They can also compare it to surrounding star systems and see if they have been influenced for an extended period of time or more recent (recent as in millions of years ago instead of billions of years).
It's not an exact science but at least it gives them a ballpark figure until they can manage to actually get to that planet and get samples. However, that may not happen in anybody's lifetime.
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 you don't have any information to provide, please don't try to act like you do.
"They take what they think they know and use it to make a guess"
Thanks for that brilliant insight.
And what exactly do we know about planet formation? If anything, we have a hunch how our system formed, but it's neither certain nor do we have any clue whether it's the norm. We already know that our system is in some ways "special", from the rather high amount of trans-HE material to its position in the galactic disc to the mere fact that it's not a multi-star system.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
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
The problem in this case is that the discovery supposedly has the potential to challenge existing planet formation theories. If that is true, then the methodology to calculate this planet's age may be flawed.
It's bigger on the surface, duh!
rewriting history since 2109
It's been done. Except when it came their turn to do it, they sent back telephone sanitization kits.
rewriting history since 2109
Jupiter's volume is 1,321 times Earth, but its diameter is only a little over 11 times Earth's. I believe diameter is what you're thinking when you say Gallifrey appears five times the size of Earth. If its volume was five times the size of Earth, the diameter (assuming perfect spheres for the sake of simplicity) would be about 1.71 times the size of the Earth. It's hard to find a good picture of Gallifrey next to Earth from that episode in which the two are equidistant from the observer, but based on the one linked below, I'd say Gallifrey is, at a minimum, 2.5 Earth diameters, giving it a volume of at least 65 Earths and a surface area. Of course, it's a fictional planet, so the real answer is that it's however big they tell us it is and everything else is a trick of the light.
http://www.flickfilosopher.com/wptest/wp-content/uploads/2010/01/dwbigassgallifrey1.gif
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....
"If it ever gets big enough to become a star and achieve fusion then the pressure pushes it out and then it gets better."
Unless you live there. Then it gets worse. Much worse.
Yo mama so fat, if she was any bigger she'd start fusing hydrogen.
I swear to God...I swear to God! That is NOT how you treat your human!
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
Too bad your comment doesn't.
Seriously, the religion-bashing knee-jerk comments are garbage. Too bad the mods don't have the common sense to just mod you as off topic or over rated and maybe you'd be forced to make an actual intelligent contribution to the conversation to maintain a good karma.
If you're only contribution to science is shouting down theists than you're not doing much better than the theists shouting down science. Go pick up a book and learn a little science and have something more than a lame warn-out old crutch to hold you up in these kinds of conversations.
So are you saying it's a Day Zero Exoplanet?
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Bad summary. The point of the article is that:
- the distance the planet is orbiting its primary is much farther out than current planet formation theories support.
- the planet is not massive enough compared to the primary to fit the theories on binary star formation.
A paper by Bailey et al. is here... http://arxiv.org/abs/1312.1265
The age is estimated from the primary star. Presumably the system formed all at the same time, star and planet together. (It's difficult to gain a planet in some other way, such as "capture," especially in such a short period of time since the star's birth.)
The planet's mass is estimated from the brightness and color of the planet. HD 106906 b is a rare case where the companion can be resolved from its primary so a spectrum can be measured. Known models of planet brightness can be used to work backwards from the brightness and color to get mass.
Distance is usually a hard one to solve, but in this case the star is bright and Hipparcos has a distance derived from parallax. A distance of 92 parsecs means that the annual parallax is 1/92 arcsec. For comparison the moon is 1800 parsecs in diameter.
but how on earth do you work out the age?
Umm, the same way you work it out on other planets??
[ducks]
And what exactly do we know about planet formation? If anything, we have a hunch how our system formed, but it's neither certain nor do we have any clue whether it's the norm. We already know that our system is in some ways "special", from the rather high amount of trans-HE material to its position in the galactic disc to the mere fact that it's not a multi-star system.
Actually we still don't know enough about stellar formation to determine how far from the norm, the Solar System actually is. The reason that we find so many oddball systems and planets is that those are the easiest systems and planets to find. We are in a form golden area of our Galaxy, far enough from the galactic center that we're not subject to it's nasty radiation and stellar activity, yet not so far that we'd lack in heavy elements. Keep in mind also that most planet detection methods rely on the target solar system being oriented edge on towards us so the planet can intercept the star's light by passing between it and us. That's going to leave a lot out.
He was German, why do you guy's think the English language part of the world should pronounce Uranus different to the way the discoverer intended?
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
"Most singular" does not mean anything. It's gratuitous gibberish.
Most is a superlative, it only makes sense when comparing 3 or more things (plural.) No comparing was being done here, and "singular" is a word whose meaning allows no opportunity to augment it with a superlative. There is no more or less singular, no least or most singular, singular is simply singular.
It's not exactly shocking to see poor English in a slashdot writeup, but this one manages to be even worse than expected.
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