Potential 'Avatar' Gas Giant Exoplanet Discovered 142
Luminary Crush writes "A gas giant of approximately 1.5 Mj (Jupiter Mass) was discovered on October 22nd around the binary star system HD 176051B. It's not known with certainty which component of the binary system the planet is in orbit around at this point as both stars in HD 176051B are relatively Sol-sized (1.07 and .71 solar masses). Named 176051B b, this new exoplanet orbits within the star system's habitable zone, and if mapped onto our solar system with relative distance from our Sun it would place the large planet between Earth and Mars. While it's unlikely that such a gas giant could host life as we know it (though it's hypothesized), the location of the big planet opens up the intriguing idea of the realization of some of science fiction's famously habitable moons, Pandora and Endor. Look no further than our own solar system to see moons with the potential ingredients for life — just add heat."
how far away is it? (Score:1)
Captain Jean-Luc Picard: Estimated time of arrival, Mr. Data?
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Re:how far away is it? (Score:5, Interesting)
Note, if we get an efficient engine that can keep accelerating (no "idle flight" period), it would be 60-70 years for earth-based observers, but much shorter for the crew. The speed limit of 1c is relevant to surrounding universe, but from the spaceship crew standpoints, the engine power - acceleration - speed - distance - travel time relation behaves in mostly newtonian way. If they expend power needed to travel at 10c according to newtonian mechanics, it will take (in their perception) 1/10 the time of travel at 1c to get there.
It all makes sense now (Score:3, Funny)
Note, if we get an efficient engine that can keep accelerating (no "idle flight" period), it would be 60-70 years for earth-based observers, but much shorter for the crew. The speed limit of 1c is relevant to surrounding universe, but from the spaceship crew standpoints, the engine power - acceleration - speed - distance - travel time relation behaves in mostly newtonian way. If they expend power needed to travel at 10c according to newtonian mechanics, it will take (in their perception) 1/10 the time of travel at 1c to get there.
Ok... Now I understand why we haven't traveled to the stars yet.
We must overestimate the power needed, so that we can underestimate the time required.
This is opposite from all engineering projects on earth, where the final design is underpowered and delayed.
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Even if we had Bussard ramscoops it still takes a while to get anywhere. I am assuming that you can't accelerate much faster than 10m per second squared without it being too hard on the crew. Of course once you get close to c the time is slowed down for the crew, but it will take a year to get up to those speeds.
Re:how far away is it? (Score:4, Insightful)
Yes, but the "nice 1g" (wow, artificial gravity problem solved!) gives us about 1 light year/year^2 acceleration. That is, gain/loss of 1c per year.
About 4 years to Proxima Centauri. 50 light years in mere 7 "subjective" years. 40 years of crew life would give 800 light years of travel distance. About 1000 parsecs in a lifetime.
Sure, we would still need engines that can provide sustained 1g. We're nowhere near that. We have rocket monstrosities that are barely survivable at 8g and more for minutes a time, and tiny farts of ~1N that can work for many years a time. Nothing in between. I believe a pure sustained fusion rocket might be capable of reaching Centauri stars, but that's still a long way away.
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I believe a pure sustained fusion rocket might be capable of reaching Centauri stars
The fusion drive is probably the easy part. What to do about hitting a grain of sand at .5c seems to be the harder one.
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Looking back at historical examples of human migration on vast scales, the typical amount of time that somebody relocated from say one continent to another was usually on the scale of months, to perhaps a year or two. A trip from Germany or Poland to California in the 1850's took approximately about a year, including travel by ship to one of the eastern US ports, and then overland on foot or wagon.
I note this because that is about the current level of technology in terms of travel to various destinations a
Re:how far away is it? (Score:4, Interesting)
There are 6 billion people. Do you really believe none could be found desperate/crazy/naive enough to want to go there?
btw, Centauri at 1g roundtrip would take 8 traveler's years and only ~12 earth years. Not quite as bad.
Still, with E=mc^2, to get 1kg to 2c equivalent you need to burn 2kg of matter in a nuclear fusion entirely. Plus whatever is needed to bring last of that fuel near the 2c... rocket fuel equations apply. That's why Proxima may be still within reach, further places - not quite.
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Looking back at historical examples of human migration on vast scales,
Who has ever seriously proposed moving vast numbers of humans between the planets, let alone the stars? Seriously, move a minimal number and breed up a new population at the far end - the work is unskilled and the workforce are generally willing to do overtime.
A trip from Germany or Poland to California in the 1850's took approximately about a year, including travel by ship to one of the eastern US ports, and then overland on foot or wagon.
As a point of fact, I suspect that the trip more often (mode or median ; pick either) took closer to a generation, with people travelling to get onto a boat, using the boat, getting off the boat, settling in the city or in the East somewhere (because
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Yes, these calculations include that.
4 light years to Proxima, top speed of 2c at halfway point, averaged speed 1c, 4 years to get there. It would be much shorter for a speedy fly-by, accelerating all the time.
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Exactly. And if he travels very close to c the universe will be very short and thus wherever he goes he will be there in a very short time. Thus relativity makes it possible to reach any point in a finite universe in human-scale time (but go fast enough and each proton you hit will be as massive as a star).
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Yes, but achieving precisely 1c would require infinite energy. We don't have that much. But if you double the energy, the perceived travel time will be reduced according to old Newtonian equations. So what if it's in fact the distance that got shortened, instead of speed being increased, ds/dt. You spent enough energy to travel at 2c according to Newton, and in your frame of reference you will get there in half the time as if you were traveling at 1c.
It may be moot for Earth people (50 light years is still
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I believe if much faster travel is invented during the flight time, a ship will be sent to pick up all the travellers and bring them to destination quickly...
Re:how far away is it? (Score:4, Interesting)
If we found a plentiful antimatter source, and built something never yet produced but only really theorised (i.e. an antimatter-based propulsion of any kind), and make it into a fairly compact but reliable propulsion system, of which one example is bought and attached to a particular extra-solar-capable chassis (of which the only two ever produced were made in the 70's and are currently used to transport a couple of LP's in a random direction that we have no control over any longer), etc. etc. etc.
As with anything to do with extra-solar propulsion, we won't see it for many, many decades and when we do, almost all our extra-solar attempts will be embarrassingly overtaken by the next-decade's attempt that will go faster (and the original mission will either have to keep going to somewhere that will be already colonised / studied even if it takes several generations, or turn back and spend their entire lives and those of their grandchildren trying to get back to Earth, or have to "merge" with the new attempt and thus have spent all their lives in a tin can when they could have just sat on Earth).
The best solution, if we were to put all our efforts to getting to any such system (which seems unlikely and extraordinarily risky), would be something based on the "water-in-the-desert" method. Go a bit of the way. Leave a small cache of supplies / fuel / resources. Return. Go again, but a tiny bit further, and leave more stuff. Go again and leave more stuff. When we have sufficient stuff cached, make a SECOND cache and so on.
In spacecraft terms, that means making something that can get to the moon easily. When we have that as an ordinary operational service, we can make trips to the next planet ready. When we have regular trips to all the planets, we can start veering slightly out of the solar system. When we have that ready, we can actually aim for the next best system by firing our best ships at it. They *will* get overtaken, but we can overtake them with an almost-empty ship with better technology, absorb their knowledge/resources and continue on the journey. Then the next ship will overtake that, pick them all up, melt down the old ship for repair-metal and continue. Eventually the people would get to some other system but we can't *ever* expect to just shoot something at the stars and expect it to work.
This isn't the Moon (a mere ten-times the Equator's distance, and your average reindeer can travel the distance of the equator about 2-3 times during his life, your car should be able to do about four-equators-worth of travel easily before it finally dies (all of mine have), etc.). This is another solar system (the NEAREST of which is 4.37 light years, which is 1,033,339,810 (and a bit) equators. A BILLION equators. And that's the NEAREST damn thing, and quite boring really.
50 years is way, way, way, optimistic for even a probe to another systems (hell, we've only "recently" done it with a probe out of the solar system at all, or a probe on another planet) - such a propulsion system would basically solve every energy need on Earth, so it's not a "small" development. To be honest, even 100, or 150, or 200 years, is being optimistic. Sometimes optimism pays off but we're not even just talking about doing something which we haven't done, at all, anywhere, in over 40 years - set foot on something that you could, theoretically, drive to within a few years in an ordinary car if you could pave a road there. We're talking about improving the entire accomplishments of all space travel by several (possibly dozen) orders of magnitude in only 2, 3 or 4 times the entire history of space travel itself (i.e. somewhere so far away that parts of a car would probably have destroyed themselves through their own radioactive half-life before it got even close).
If we could do that with cars, extrapolating from the 60's, then we'd all be driving 1000mph cars that get 500mpg (actually, probably a LOT more than that).
It's not *impossible*, it's just silver-suits and three-course-meal
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I'm not even so sure about overtaking; even our extrasolar spacecraft from the 70's could have been noticeably faster (using instead of medium launcher something like, say, Saturn V with NERVA upper stage and, on the probe, nuclear reactor with ion thruster) - it just didn't make sense for the primary mission (would limit flyby times), it would be quite a bit more expensive.
It's not just the tech that keeps us firmly on Earth now. And in the future - despite our wishes, it might very well be that the best p
How is this related to Avatar? (Score:5, Insightful)
So, it's a much farther distance (50 ly), has a binary system (instead of a triple system), and the planet is bigger than Jupiter (instead of smaller).
How is this related to Polyphemus from Avatar more, than, say, Bespin? ... come to think of it, both Avatar and this discovery are both overhyped. Objection withdrawn.
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The planet has heavy traces of Unobtainium in its Spectre, of course.
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The advanced high res 3-D telescopes have discovered blue creatures wandering on this planet, in 3-D!
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Yes, Class-M, as in Marketingtastic.
Simple question... (Score:2)
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Re:Simple question... (Score:5, Informative)
short answer: If [Jupiter] were about sixty times more massive than it is, it would indeed be a star [starryskies.com]!
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The minimum size of a star is thought to be about 83 times the mass of jupiter.
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I didn't know mass was a unit of size. :p
Re:Simple question... (Score:5, Informative)
I didn't know mass was a unit at all ;)
When talking about how big something needs to be to become a star though, mass is pretty much your only useful measure.
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Well yes and no, the point is that below that mass, there isn't enough material to sustain fusion the way a star does. Sure there are a few more constraints, but mass is the relevant one here.
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It is when you think about compacting it down into the smallest volume such that nuclear fusion starts up.
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plus/minus 10 jupiter masses. The distinction between planets and brown dwarfs is really fuzzy.
Even Jupiter emits more light in some frequencies than it receives from the sun.
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Even Jupiter emits more light in some frequencies than it receives from the sun.
More generally, it radiates more energy than it receives from the Sun (with a different mechanism [wikipedia.org] than in a star of course)
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Even Jupiter emits more light in some frequencies than it receives from the sun.
More generally, it radiates more energy than it receives from the Sun (with a different mechanism [wikipedia.org] than in a star of course)
Most planets radiate more heat than they receive from the sun, of course. Including Earth, which generates internal heat by radioactive decay and radiates it away as part of its infrared output.
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Jupiter appears to be near the breakaway point. Saturn, despite being much further, might receive more energy from the Sun than it radiates. Earth receives four orders of magnitude more [am.ub.es] than it generates internally.
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The distinction between planets and brown dwarfs is really fuzzy.
No it's not. The distinction is at the point where the accreting planet achieves sufficient mass to start to burn lithium. Finding out what that mass is is moderately fuzzy (it almost certainly varies with metallicity of the progenitor material) ; measuring masses is also moderately fuzzy (i. sinand all that jazz) ; determining if the object is depleted in lithium compared to it's progenitor material is also fuzzy. But the criterion is not fuzzy.
To use the traditional car analogy - you can argue whether the
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I think the threshold is not mass but origin/temperature. That is, a gas giant that is ablaze with thermonuclear fusion (or was in the past) is a star. Of course this is possible only above certain size/mass but there may be biggest gas giants slightly bigger than smallest stars.
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http://en.wikipedia.org/wiki/Star#Mass [wikipedia.org] claims you can't get below 75, but it depends on how much metal you are willing to allow your 'gas giant' to contain.
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http://en.wikipedia.org/wiki/Star#Mass [wikipedia.org]
Claims 75X mass of jupiter (depending on the extent to which you are willing to allow your planet to have a metal core rather than be mostly gas).
SI Units (Score:2, Informative)
1.5 Jupiter Masses = 2.8479 * 10^27 kg, in case anyone was wondering.
Big Just (Score:2)
Look no further than our own solar system to see moons with the potential ingredients for life -- just add heat.
That's a rather big "just", since gas giants require cold to form. They're made of hydrogen and helium, which simply doesn't "stick" to a small proto-planet if the temperature is anywhere near the melting point of water. Of course, you could heat the environment of an already-existing gas giant, but how would that happen?
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Read that sentence you quoted again, he's talking about the moons of the gas giants, not the gas giants themselves. If you want to colonize the moon, does it matter if the main planet is a gas giant or not? It just has to exist as something for the moon to orbit around.
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Yes, he's talking about the moons of the gas giants, which tend to be located rather near the gas giant itself, as far as distances in solar system's scale are concerned. Because they are near the giant, they are about as far from their sun
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If they're about as far from their sun as the giant, they get about as much solar radiation per square meter, and should thus be about as warm (or cold). In other words, if the gas giant is really really cold, so will the moon be.
Exactly. So? Where did anything I say contradict that? Read the summary. He's saying that if this planet is close enough to be warm, so will the moons be warm.
And we aren't talking about colonizing moons, we are talking about life evolving in one. So double fail on your part.
Uh, nope, quote the SUMMARY: "the location of the big planet opens up the intriguing idea of the realization of some of science fiction's famously habitable moons". Not that there's any difference anyway; the point is whether or not it can meaningfully support life.
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It would have to be orbiting something close enough and massive enough to cause tides; otherwise, how would the chemicals that create life mix? [slashdot.org]
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...and yet we sort of have just such a thing in our system - a moon hot to the point of being, by far, the most volcanically active body in the system.
All this ignoring how many extrasolar hot Jupiters and hot Neptunes we're discovering - you people really never heard about them, about planetary migration in general?
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If you're talking about Io, it has average surface temperature of 110 Kelvin (-163.15 degrees Celsius or -261.67 degrees Fahrenheit), and even max is 113 Kelvin. That's not habitable by any water-based lifeform.
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A temperature close to all other Galilean moons (or indeed all moons of Jupiter) - that's because of small size and hence tenuous atmosphere (also magnetosphere of Jupiter stripping it) unable to retain heat, not lack of heating.
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Conditions on Io seem fairly stable...
Plus any differences during "long" orbits of practically any moon getting appreciable tidal heating are insignificant compared to the basic facts of heat retention, slow rates of convection, etc.
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Yes, Io is simply heated far too much than what we would consider "nice" and is too small to retain any appreciable atmosphere (it does tend to stabilize temperatures on Earth, works wonders on Venus which has a day on the order of one year). Doesn't change how it's a good case scenario for extending habitable zones of perhaps millions solar systems just in our galaxy.
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Who says it's cold? Do you think that just because the gas giants in our solar system are cold, every gas giant in the universe is? Ours are cold because of their distance from our sun. Read the summary.
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Of course, you could heat the environment of an already-existing gas giant, but how would that happen?
Yeah, how in the universe [wikipedia.org] this could ever [wikipedia.org] be possible? [wikipedia.org]
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Not really fusion, mostly "friction" of matter in the accretion disk. Wouldn't be very long-lived. Wouldn't be dim; in fact, it would most likely hugely outshine the central star of the system.
(and you know, we have many decent examples of what happens when a black hole appears inside a place with a lot of matter; the "fusing gas shell" in turn can't be really supported on anything)
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It forms a disk just due to conservation of angular momentum and how the matter on initially, what is in essence, high inclination orbit around the black hole (the parts starting "far" from the equator) can't really keep that "orbit". Nucleosynthesis doesn't appear to be major way of energy release around black holes. Singularity doesn't need to be very large to get things quickly going where there's a lot of mass available; just large enough - and when that is the case, there doesn't appear to be a mechani
We might have found Pandora? (Score:1)
So if we launch all of our nukes now, how long would they take to get there? Goddamn furries.
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If we do develop FTL travel, some tree-hugging idiot is bound to jump into the past and try to stop the nukes from ever being launched.
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/me looks around...does the Universe seem greatly influenced, by some "civilization" from the "future" that developed FTL, via processes not following the expected natural ones?
Nope; quite likely no FTL possible in this Universe (unless one wishes to subscribe to one quote of sir Arthur C. Clarke, "it may be that our role on this planet is not to worship god, but to create him")
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We call it money.
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We already created one, and all humanity worships it, even if can't do FTL. And if well is not based in very advanced technology, people think that with enough of it they can do magic.
We call it money.
Geeze I thought you were going to say "Apple Inc" not boring old "money".
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Such a civilization might have even traveled right back to the big bang and influenced things so that the physical constants come out as they have and everything comes to pass as it has (as seen from our perspective). You wouldn't be able to tell the difference if they did, so the discussion is moot anyway.
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Not exactly moot, if it still means no FTL for us anyway.
Intelligent life... (Score:3, Interesting)
If intelligent life evolved out of a moon ecosystem where the main source of heat was tectonic stress, and the main liquid was methane or ammonia, you can bet they'd kick our ass.
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If intelligent life evolved out of a moon ecosystem where the main source of heat was tectonic stress, and the main liquid was methane or ammonia, you can bet they'd kick our ass.
...slowly.
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There is a very nice SCI-FI story about life in strange locations here, it is called "Passages in the Void"
http://localroger.com/revelation-passage/ [localroger.com]
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I always liked Sagans version better. (Score:3, Interesting)
The Cosmos Series had a very good explanation of floaters and sinkers [youtube.com] and some predators etc... /huh huh huh floaters.
I am an author of the study (Score:5, Informative)
I am an author of the paper in which this discovery was reported. You can find a copy of the paper here [arxiv.org].
While the planet probably is near the habitable zone, this isn't the first time a giant planet has been found in the habitable zone of a star, and while it could have moons, there isn't any reason to speculate more about this planet than any of the others.
However, this planet is important for two other reasons:
1. It was the first planet discovered using a technique called "astrometry", which is measuring the positions of stars in the sky, as the move up/down and left/right in reaction to a planet orbiting it. This technique has the potential to find earthlike planets in the habitable zones of nearby stars.
2. It is found in a binary system and the second star is close enough that its gravity would have impacted planet formation. The leading theory of planet formation, called "core accretion", requires millions of year for planets to form, as dust in a disk around the star collides together and clings electrostatically (similar to the way dustballs collect on a hardwood floor). Eventually the dustballs grow large enough to be considered rocks, those collide and grow bigger, etc. But the second star's gravity would cause the dust to be swept out of the system in just thousands of years, far too little time for core accretion to occur. Thus, we need a different mechanism to explain planet formation in this system. This isn't the only such binary, but it this study does offer more controlled statistics of how frequently such binaries host planets, and these facts combined show that some had to form in the binary itself---the chances of a binary interacting with another star (that originally hosted the planet), leading to an exchange where the binary picks up the star, are much too small to explain the high rate observed.
Also, here [space.com] is another press story covering the discovery (by the way, stars have multiple names---don't be confused that this article calls it "HR 7162" and the other one refers to "HD 176051"---they really are the same system). The third figure on the right hand panel is particularly useful.
Any questions? I'll try to answer responses to this post.
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Any questions? I'll try to answer responses to this post.
How can so much about the planet be observed without knowing which star the planet orbits? I'd think that information would be critical before any of the other information could be inferred.
Re:I am an author of the study (Score:4, Interesting)
Any questions? I'll try to answer responses to this post.
How can so much about the planet be observed without knowing which star the planet orbits? I'd think that information would be critical before any of the other information could be inferred.
The planet was discovered by measuring variations in the separation of the two stars. Their separation changes very slowly as the stars orbit each other, and on top of that motion, we found a very small wobble in their separation that repeats every ~3 years. That 3 year effect is the reaction of one of the stars to the planet orbiting it. Since we are measuring the relative separations of the stars, there is no way to know which one is wobbling. For the science content, it turns out not to matter nearly as much as one might think.
Radiation belts? (Score:2)
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My understanding is that the moons of Jupiter are not human-habitable with any current technology on account of fierce charged particle radiation from the strong magnetic fields. Do I have this right, or does this only apply to Io, which is in one of the radiation belts?
With sufficient shielding, this could probably be overcome. However, there are other reasons those moons might not be comfortable places for humans: wrong temperature, no liquid water on the surface, no atmospheres, etc. On this new planet, it doesn't seem likely we'll be measuring its magnetic field any time soon, so it's a bit early to speculate more.
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(question is how much we would care; those radiation numbers certainly look awfully high)
Regarding magnetic field: due to interactions in the field of Jupiter, its radio emissions can apparently "outshine" the Sun; occasionally...
Maybe somebody who's strongly into radio astronomy, and available to you, can comment if our radio telescopes have the potential of resolving such source?
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(question is how much we would care; those radiation numbers certainly look awfully high)
Regarding magnetic field: due to interactions in the field of Jupiter, its radio emissions can apparently "outshine" the Sun; occasionally...
Maybe somebody who's strongly into radio astronomy, and available to you, can comment if our radio telescopes have the potential of resolving such source?
We don't yet have radio telescopes powerful enough to detect the radio emission of a planet like Jupiter around another star. There has been some recent speculation that if the radio brightness increases as the planet is brought closer to its star, and if that scaling is optimistically strong, then maybe some next generation radio telescopes could do so for the closest-in giant planets (i.e. the hot Jupiters), though this is planet not one of those.
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With current telescopes what's the distance limit that we can use astrometry with any hope of accuracy (how many parsecs out can this technique be used)? In a similar vein are you using a single viewing session with one (or a single set) of telescopes or are you making multiple observations at different points in the year to create a virtual optical array? Does this increase the astrometric measurements in a meaningful way?
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With current telescopes what's the distance limit that we can use astrometry with any hope of accuracy (how many parsecs out can this technique be used)? In a similar vein are you using a single viewing session with one (or a single set) of telescopes or are you making multiple observations at different points in the year to create a virtual optical array? Does this increase the astrometric measurements in a meaningful way?
With current telescopes? Well, the telescopes we used to do this work have been decommissioned (and bulldozed!), so I guess they're not current anymore. HST and some large ground-based telescopes are doing astrometry about 5x less precise than our program. The Europeans are building an array in Chile that should be able to do comparable precisions as our study (though over larger and more versatile set of target stars). Let us assume by "current" we mean something operating with precision similar to our
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Would it be easier to detect the existence of large (small planet-sized) moons around a gas giant than earth-sized planets around a star? Would not the perturbation of the gas giant be easier to detect because the mass ratios are closer (large moon to gas giant vs earth-sized planet to star)?
If so, detecting the gas giant in the habitable zone and then looking for evidence of large moons or companion bodies could allow detection of candidates for life.
I assume this would entail detailed, direct observation
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Would it be easier to detect the existence of large (small planet-sized) moons around a gas giant than earth-sized planets around a star? Would not the perturbation of the gas giant be easier to detect because the mass ratios are closer (large moon to gas giant vs earth-sized planet to star)?
If so, detecting the gas giant in the habitable zone and then looking for evidence of large moons or companion bodies could allow detection of candidates for life.
I assume this would entail detailed, direct observation of the gas giant, but I would imagine that will happen sooner than detailed, direct observation of an earth-sized body.
Not with this method, since we are seeing the reflex motion of the star, which wouldn't be very different at all if the thing orbiting it were a planet by itself or a planet with a moon.
However, for the transit method of planet formation that the Kepler mission is doing, we see the planet move in front of its star, periodically blocking the light. If the timing isn't perfectly periodic, that may mean its arriving too soon sometime, and too late others. This could be due to a moon orbiting the planet. Thi
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As I understand it... the bulk of the large moons in our solarsystem are made of low density materials essentially they're mini-frozen Jupiters in themselves or water ice balls like Enceladus. Wouldn't the formation of an Earthlike planet be precluded so close to a Jovian mass... Something with a substantial rocky core like Earth's forming at the same distance as a Jovian would have become a Jovian itself and most likely would have merged with the parent body? The Inner planets as I understand it were Jovians that had the bulk of thier gas envelopes blown clear during our Sun's T'Tauri phase of super strong solar winds.
The major moons in our solar system have densities between those of the terrestrial worlds and those of the giants. I certainly would not consider them to be mini-Jupiters.
Planet formation isn't as simple as our old ideas of "if it forms here, it will be a gas giant, if not, it will be terrestrial". Clearly there are a lot more details that we don't know yet.
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I've always thought that a binary system would create eddies in the dust and that mass caught in the eddies would coalesce quite quickly (incidentally, becoming a mass big enough to draw in more mass at an increasingly faster rate).
I haven't seen any of the planetary creation models, so how much do they consider this kind of eddying and coalescence? I would think the eddying would be greater in a binary or trinary system than a single star system.
Yes, an alternative model of planet formation called "gravitational instability" or "gravitational collapse" predicts that planets form in this way. That method is predicted to form planets very rapidly, and while there is not universal agreement on the subject, it seems likely that this is enhanced in binary systems. In the study, we discuss that this alternative model is one way to solve the problem of how this planet (and similar other ones) formed. This finding offers significant support to that alte
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Do you have an impression that double / multiple star systems were up to this point neglected in searches of planets? While "gravitational instability" model perhaps even suggests they are at least comparably likely to form planets?
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Do you have an impression that double / multiple star systems were up to this point neglected in searches of planets? While "gravitational instability" model perhaps even suggests they are at least comparably likely to form planets?
It's actually a bit harder to find planets in binary systems using most of the current techniques. For example, the Doppler method is much more challenging when there are two spectra present to disentangle. When making measurements of extremely high, cutting-edge precision, and such complications can drastically reduce that precision. Similar, the transit technique is more challenging because there is more light present and because those studies usually require Doppler follow-up anyways to avoid false-po
Orbits (Score:5, Informative)
It's not known with certainty which component of the binary system the planet is in orbit around at this point as both stars in HD 176051B are relatively Sol-sized (1.07 and .71 solar masses).
Orbits do not work that way. The planet is orbiting around the center of gravity of the binary star/planet system. Since this is a binary star, this very well might be a point in empty space.
Re:Orbits (Score:4, Informative)
For a "stable" barycenter orbit, it would have to be very far away from the stars relative to the stars own separation. IIRC even then stable orbits are problematic for the scales we are talking about.
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If only that point didn't move.
Not so fast! (Score:2)
I'm sure a bunch of hater scientists will discover there was a Fern Gully planet found 2 decades before.
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Not to mention the Dances with Wolves planet, some time before that!
Trying to find other habitable planets is futile.. (Score:2, Troll)
This post is probably going to get modded as a troll... it's certanly got all the earmarks of it, but all I can say is that this is still my sincere belief on the matter. I see absolutely no point to the exercise to finding habitable exoplanets. At all.
What good does it do to know that habitable exoplanets are out there? Can we send people there? And even if we did, in the enormous time that it takes them to reach their destination, would the descendants of the original crew even be the sort of peopl
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Finding as much interesting stuff as we possibly can now, will help tremendously when we finally have the technology to send probes in a reasonable time.
And developing new techniques for searching for interesting stuff is important as well.
If we listened to you, in 100 years or so when we can send something somewhere, we would just have to cross out fingers, close our eyes, and point
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What good does it do to know that habitable exoplanets are out there? Can we send people there? And even if we did ... (rest of depressing post)
Tiger got to hunt
Bird got to fly
Man got to sit and wonder - why, why, why?
Tiger got to sleep
Bird got to land
Man got to tell himself - he understand.
(Kurt Vonnegut, Jr.)
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At least some of us might get a quite decent image (puns, et al) - many nearby systems should be close enough for some good interferometer with a way of canceling-out the starshine; even JWST might give something not bad, for nearest systems, especially with some starshade added, flying in front of it in unison.
But yeah, people raised on too much on scifi travels will be disappointed either way...
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They just needed to use neutron bombs on those Navi and mine the stuff in peace....
Damned blue people always getting in the way of progress, first it was the Smurfs and now these Navi things!
Nuke them from orbit, its the only way to be sure!