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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
I would guess it's an estimate based on the age of the star, which we can figure out. Perhaps the age of the star combined with what we know about the speed of planet formation?
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.
Becoming a star requires at a minimum many times the mass of jupiter. As small stars exist, there's therefore a likelihood that there are gas giants almost as big a the minimum to make a star.
A quick google seems to suggest that's 8% the size of the son
As Jupiter is 0.1% size the son, 11x the size of jupiter doesn't seem that big. We should be able to find "planets" up to almost 80x larger
http://www.space.com/21420-smallest-star-size-red-dwarf.html
http://www.wolframalpha.com/input/?i=jupiter%20mass%20compared%20to%20sun&t=crmtb01
The Gravity must be immense, we'll need to ban their Olympic athletes from participating in the summer games.
Harrison's Postulate - "For every action there is an equal and opposite criticism"
Gallifrey!
But seriously. The coincidence of this timing is just... amazingly awesome.
Guys, accept calling it Gallifrey now. I'm sure everyone knows the Whovians are going to start some massive petition to do it anyway.
http://www.scientificamerican.com/article.cfm?id=how-do-scientists-determi
Harrison's Postulate - "For every action there is an equal and opposite criticism"
it should get there at just about the right time to teach the pre-dawn humans about the wonders of violence. How about instead we fill this one with Youtube cat videos and see how the planet evolves?
Linux -- the Ultimate Windows Service Pack
It was originally a small planet and it was even demoted to a dwarf planet. When the protests to reinstate it didn't work, the protesters said "oh yeah? watch us". They poured material on it. A lot of it.
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.
Around 13 Jupiter masses they become known as brown dwarves. So it's not that we don't know of objects that are of this mass. I think where some of the question comes in is if brown dwarves should be considered stars or not.... I'm not sure how the IAU terms this.
Wikipedia says that at 13 times the size of juptiter you get something that can ignite and you get a brown dwarf.. How that is calculated is beyond me..
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
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.
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Just kidding . . . but, seriously, I am really not looking forward to when they actually do discover a death star . . .
Sdelat' Ameriku velikoy Snova!
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.
whatever that means.
It is 11 times the mass [FTFY] of Jupiter, and that's what makes it a most singular discovery.
Much as I enjoy the Sherlockian prose, every time we discover a new most massive planet, it's going to be a singular discovery.
The missing context here is: how massive was the previous recorder holder?
systemd is Roko's Basilisk.
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.
It is 11 times the size of Jupiter, and that's what makes it a most singular discovery.
Oh dear. Do we have to have the talk again?
systemd is Roko's Basilisk.
I wonder, when astronomers say 11 times the size of Jupiter, does that mean 11 times the radius, the mass, or that you could fill the sphere of its volume with 11 jupiters? Or the circle area as seen from earth?
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.
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
I remember reading something some time ago about how light from a distant object is used to determine the composition of a star, or a planet. As different elements produce a difference wavelength of light, this can be used to determine the composition of a stellar object and by comparing this to other known objects with similar composition, this can be used to determine how the object was formed and it's relative age.
OK I answered my own question with some googling.
http://www.universetoday.com/76495/the-hunt-for-young-exoplanets/
foo mane padme hum
That only works if you can cut it in half first.
How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
"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.
My brown dwarfs are typically much smaller than that.
Science bitch!
the Tall Man can do custom orders?
As the set of planets grows, theories will have to change as we have based the original ones on a single sample that may or may not be representative of the full set.
It's like basing an entire theory of construction of buildings on De Aar, South Africa and while it may explain most small towns, the suburbs of most cities, it will fall apart completely when you try and explain Manhatten or wooden houses in the US with it.
Trying to become famous by taking photos. Visit my homepage please.
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!
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.
Maybe it's just 11x closer than they think it is, and moving away faster than expected. Would still be an interesting system to find.
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
Yo mama so fat, if she was any bigger she'd start fusing hydrogen.
Yo momma SO fat, every time I am done visiting her, I have to break orbit.
The three laws of thermodynamics:(1) You can't win. (2) You can't break even. (3) You can't even quit.
This object is in an ugly middle between being a separate star or just a planet. Are there any models that consider both star and planet formation as the same process? If we built our programs to model one or the other, it's easy to see why we wouldn't have predicted distant but non-fusing binary partners. Note, it seems that 650 AU is quite distant even for a binary companion, alpha centauri A and B wobble between 16-32 or so AU between them, and have a larger orbit than most.
A certain amount of mass equals a certain amount of pressure, which is what's required to start hydrogen fusing.
One day I feel I'm ahead of the wheel / the next it's rolling over me / I can get back on / I can get back on
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.
Wikipedia says that at 13 times the size of juptiter you get something that can ignite and you get a brown dwarf.. How that is calculated is beyond me..
From hydrostatics: the more mass you build up, the higher the pressure --and the temperature-- becomes in the core, and then you reach a point where the temperature is high enough to start fusing stuff up (as per definition of 'a star'). This, for hydrogen, happens at some mass limit or other which is at around a few Jupiter masses.
It is a back-of-the-envelope calculation really, though there are a few other, more sophisticated models, around.
The three laws of thermodynamics:(1) You can't win. (2) You can't break even. (3) You can't even quit.
So are you saying it's a Day Zero Exoplanet?
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Ah. Typing goof. Meant to say bigger, not better. Often times those are as misused as the mass and size situation though :).
"People who think they know everything are very annoying to those of us who do."-Mark Twain
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.
At least if we assume that the planet was formed with the star. But what if the planet had formed around another star, and then was ejected from that system due to some disturbance, to be later captured by the star it is circling now?
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.
Am I wrong? It's exactly what happens. A guess based on the slimmest of knowledge. I can't count how many times I've seen these sudden bursts of enlightenment get changed when everything they thought they knew gets turned upside down. It's a guess and only by the loosest term an educated one. I'm sorry if the facts hurt your feelings.
However they can guess based on it's radiation level and it's decay of said rad signal.
That is partially related to how they can look at ages of planets they get samples from or can send probes to, by looking at isotope ratios. But you're not going to get any sort of radiation decay from a planet light years away, only stuff from active processes or in the rare chance you catch something within a million years of still cooling off and looking at IR.
its a failed star, ergo had it become a star it would be the most common system type
BINARY
I'm sick of all these "x times the size of Earth" metrics.
We have a standard measurement system. Let's use it.
For the scientifically minded among us, how many football fields big is this planet?
| No fusion = planet, deuterium fusion = brown dwarf, hydrogen fusion = main sequence star.
I thought that our star, (the sun), used deuterium fusion as it's primary mechanism for producing energy, and that it's not hot enough to produce direct hydrogen fusion????
(With the mutual annihilation of positrons and electrons produced by the deuterium fusion producing a bit less than 10% of the sun's energy output.)
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]
At the sun's mass Deuterium isn't needed but could be there. Even the largest brown dwarf has a problem with anything beyond lithium.
No offense, but he kept his remark short and sweet. He didn't go into some serious diatribe about how religion is tearing down society or more. Because of that, I give him a pass. I would have probably worked the system a bit more explaining the evils and blah blah blah, I am bored and think I will go get a cookie.
Place something witty here
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.
More than an upper limit. Unless the planet is a captured rogue, knowing the age of the star gives you the age of the planet, pretty much. If you know the age of someone's heart, you know the age of their head, too (transplant patients excepted).
"Convictions are more dangerous enemies of truth than lies."
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.
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.
At least if we assume that the planet was formed with the star. But what if the planet had formed around another star, and then was ejected from that system due to some disturbance, to be later captured by the star it is circling now?
That would be kind of tricky. The planet is moving at escape velocity from it's original star, in most cases, encountering another solar system would have it either just passing through, or it would wind up in a very eccentric orbit. which would not necessarily be in the same plane as the local ecliptic.
Becoming a star requires at a minimum many times the mass of jupiter. As small stars exist, there's therefore a likelihood that there are gas giants almost as big a the minimum to make a star.
A quick google seems to suggest that's 8% the size of the son
As Jupiter is 0.1% size the son, 11x the size of jupiter doesn't seem that big. We should be able to find "planets" up to almost 80x larger
http://www.space.com/21420-smallest-star-size-red-dwarf.html http://www.wolframalpha.com/input/?i=jupiter%20mass%20compared%20to%20sun&t=crmtb01
Those are objects known as Brown Dwarfs which would put them at a different category than Jovian planet. I believe that the minimum mass to establish fusion is something on the order of one tenth solar mass. Brown Dwarves radiate Infared radiation due to heat from residual gravitational collapse. Presumably the standard is considerably higher than Jupiter which also radiates more heat than it absorbs from the Sun.
That doesn't work for every planet. Clearly, your head is stuck in Uranus.
I felt bad for the man who had no signature, until I met a man who had no comment.
Holy fuck, you don't know how to spell 'sun'?
You know, if Johann Elert Bode, the man who ultimately named Uranus, had any inkling that the naming of the planet in this way would lead to the untold gazillions of sexual puns made with his choice, he would have killed himself.
There is a class of objects between planets and red dwarf binaries.
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How many Olympic pool sizes would it take to fill its volume?
When Uranus was discovered the common pronunciation for the old Greek sky god's name was something akin to urine-us, which at the time was considered far more vulgar than the ur-anus pronunciation. Today it is the other way around. Who knows which pronunciation will be considered ruder (or more childish) a few centuries from now.
Just because you are paranoid does not mean that no-one is out to get you.
I read both articles but did not see how old the star it's orbiting is. Pardon me if I missed it, I just woke up. It sounds to me like a failed star from the same general region drifted into the gravity well of the star in question, and found a cozy place that far out. Even if the star it is orbiting is much older, they could have still formed from the same gas cloud. Just because it has taken up orbit, does not mean formed there. Perhaps it's mass results in some kind of wild slingshot orbit... perhaps, perhaps, perhaps.
Perhaps this is just another example of the more we learn about science and the universe, the less we know and understand. Funny how it works that way.
Brought to you by Carl's Junior.
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?
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A planet coming from outside the system would pass right through, having too much momentum to stick around because any speed it gains from falling into the system's gravity well is exactly how much it will need to leave. So it needs some way to shed momentum, requiring a significant amount of other mass to fling away from the system, i.e. another planet. So while there might be some differences between the planet ejected and the one that came in, you would still have to deal with a planet or one of several planets forming at that distance. Not to mention the chances of it lining up like that are pretty small.
You know, if Johann Elert Bode, the man who ultimately named Uranus, had any inkling that the naming of the planet in this way would lead to the untold gazillions of sexual puns made with his choice, he would have killed himself.
Ummm, why would you confuse scatological jokes about rectal sphincters with sexual puns?
D-D fusion doesn't get you any positrons (nor neutrinos, which have been observed). D-D fusion is also much easier than p-p fusion. The sun is quite capable of performing p-p fusion, which produces deuterium and positrons, and then the deuterium gets used up too. The details of the process, and what happens after deuterium because it is temperature dependent, is covered on Wikipedia
Couldn't a pre-existing planet be captured by a new star? I can imagine a situation where a star going dark sends its planets drifting through deep space only to be captured again later.
- Michael T. Babcock (Yes, I blog)
Why do these stupid Christians keep challenging established FACT. We all know how planets form. It is FACT. Science Works!
You're correct. It's spectroscopy, and it's a second year university physics lab experiment (or was, for me, 20 years ago) to learn how to do.
'guesswork' and 'hunches' people can get stuffed.
It could twat into a planet that's already there. Or several.
Maybe that's why it's so big?
"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.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Friends don't let friends enable ecmascript.
Yo mama so fat, if she was any bigger she'd start fusing hydrogen.
Yo momma SO fat, every time I am done visiting her, I have to break orbit.
YO momma so fat, I have to calculate delta-v when driving past her apartment.
I'm guessing you meant 1800 arcseconds, unless the moon really let itself go while I wasn't looking and is now several thousand light years across. :)
Procrastination Man strikes again!
Or alternatively, you could pronounce it, instead of "urine-us" (Yor-in-us), you could say, "Oar-ahn-us". Not sure that would be "correct" but it's got more dignity than either of the other two.
Or just go with the flow and name it's next moon they discover, "Enema"..
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
Ok, I admit it was lame. But according to the Wikipedia article, Uranus beat out the previous name, given after George III. The planet would have been called Georgium Sidus. Yech... how exactly is that a great name for a planet? https://en.wikipedia.org/wiki/Johann_Elert_Bode
I felt bad for the man who had no signature, until I met a man who had no comment.
It would still have to interact with another planet of comparable mass and orbital position in order to be captured. So one way or another, you have to deal with large planets at that distance having formed.
I prefer Urr-a-nos
Don't forget gravitational lending and wobble as other methods to detect exo planets.
Even if it's dark, it's star would still be there, same mass bending space time to form a gravity well. If tinge star blew up, it would probably destroy the planet. If it escaped, you have an 11 jupiter sized bowling ball just waiting to be captured by another star, at just the right angle for a stable orbit?
A second year physics or chemistry student can probably figure out what elements are shown in a cleaned up spectrum. Getting that spectrum from an exoplanet is a bit more difficult and error prone. Getting from the elemental composition to an estimate of the age of a star is problematic enough as is, and astronomers just assume the planet is about the same age as the star.
Wait. who's twat is so big that it absorbs planets?!
Yo mama so fat, she's got a heart of pure diamond!
Don't forget gravitational lending .......
"Hey Jupiter, I'm feeling a bit lightheaded.. can you lend some of your gravity please?"
In a huge universe, anything's possible ...
- Michael T. Babcock (Yes, I blog)