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Potential 'Avatar' Gas Giant Exoplanet Discovered

timothy posted more than 3 years ago | from the ewoks-await-their-moment dept.

Space 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."

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142 comments

First bloat! (-1)

Anonymous Coward | more than 3 years ago | (#34009826)

Yay for gas giants \o/

how far away is it? (0)

ionix5891 (1228718) | more than 3 years ago | (#34009832)

Captain Jean-Luc Picard: Estimated time of arrival, Mr. Data?

Re:how far away is it? (2, Informative)

Lanteran (1883836) | more than 3 years ago | (#34010120)

in a fusion powered orion, it falls far short of the 50 year rule; 500 years with current technology. If we found a plentiful antimatter source, we could cut this to about 60 years.

Re:how far away is it? (4, Interesting)

SharpFang (651121) | more than 3 years ago | (#34010162)

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 (2, Funny)

captainpanic (1173915) | more than 3 years ago | (#34010376)

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.

Re:how far away is it? (1)

rossdee (243626) | more than 3 years ago | (#34010730)

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? (3, Insightful)

SharpFang (651121) | more than 3 years ago | (#34010902)

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.

Re:how far away is it? (1)

silvermink (1890578) | more than 3 years ago | (#34010990)

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.

I don't quite understand what you mean here, it makes little sense talking about newtonian mechanics when the speed is near 1c. If travelling at 1c the Universe will be infintesimally short to the traveller (due to length contraction), and thus wherever he goes he will be there in no-time.

Re:how far away is it? (1)

John Hasler (414242) | more than 3 years ago | (#34011744)

If travelling at 1c the Universe will be infintesimally short to the traveller (due to length contraction), and thus wherever he goes he will be there in no-time.

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).

Re:how far away is it? (1)

SharpFang (651121) | more than 3 years ago | (#34012546)

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 50 years of flight no matter how much energy they pump into the engines), but it means no need for hibernation/cryogenics for the travelers (who will perceive the 50 years as 7 years of ship time).

Re:how far away is it? (3, Interesting)

ledow (319597) | more than 3 years ago | (#34010358)

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-pills material at the moment, because we have absolutely NOTHING that will bring those numbers under any sort of reasonable upper limit, even if cost, resource availability, etc. isn't an issue. When we solve those problems, we also almost automatically solve the world's energy problems, and thus probably things like world hunger, etc. It's not a question of going further / faster than those who went before (e.g. getting to orbit instead of just a plane, getting to the Moon instead of just orbit, etc.), or being brave, or putting our best men on it, or convincing any one government to put their entire GDP into just space travel, it's so far BEYOND that it's inconceivable at the moment. It's the equivalent of expecting your next car to last for 100,000,000 miles, do several thousand mph, on a thimbleful of petrol, and come with breakdown assistance without paying extra.

Re:how far away is it? (1)

sznupi (719324) | more than 3 years ago | (#34010572)

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 practical thing allowed by this Universe is some variant of nuclear propulsion (or for small unmanned - starwisps [wikipedia.org] for example; still at best around an order of magnitude less than c, anyway), all our data so far certainly strongly suggests it. And technologically, if we really wanted to, we can have capabilities for interstellar probe decently soon.

But as you say, it would require basically whole GDP of the planet for the next few generations.

(BTW you assume too big of a final hop in the "cache / gradual" approach, IMHO - there are many more outposts and local resource sources possible along the way, in the Oort cloud; estimations put their number maybe even at one trillion; I guess that's how our colonization will in the end look like, very gradual over the course of millennia - and with some groups eventually hitching a ride in an Oort cloud of another close-passing star. Maybe some embryo colonization ships, at most - one every few decades shouldn't put too much of a strain on the system)

Re:how far away is it? (1)

a_hanso (1891616) | more than 3 years ago | (#34010662)

how many libraries-of-congress-burned-per-second would the energy requirement for that be?

How is this related to Avatar? (4, Insightful)

The_mad_linguist (1019680) | more than 3 years ago | (#34009884)

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.

Re:How is this related to Avatar? (0)

Anonymous Coward | more than 3 years ago | (#34009896)

new bullshit detected to attract founding, name everything exo avatarish

Re:How is this related to Avatar? (1)

siddesu (698447) | more than 3 years ago | (#34010068)

The planet has heavy traces of Unobtainium in its Spectre, of course.

Re:How is this related to Avatar? (0)

Anonymous Coward | more than 3 years ago | (#34010086)

And when will we get there?

Given that the warp-drive will be invented in 2063:

2063-2011= 52 years before we get the technology.
Probably warp 1 will be the initial speed of the drive and that equals to 26x the speed of light.
Distance is 50LY/26, so about 2 years to get there.

I would say that we should be there in 54 to 55 years. Assuming that FLT is ready for prime time in 2063...
I'm sure that Virgin Galactic and Scaled Composites are working on a joint venture as we speak.

Re:How is this related to Avatar? (1)

Lord Lode (1290856) | more than 3 years ago | (#34010726)

The advanced high res 3-D telescopes have discovered blue creatures wandering on this planet, in 3-D!

Well what are we waiting for? (0)

Anonymous Coward | more than 3 years ago | (#34009904)

Let's go mine the #$@! outta it.

Simple question... (1)

Burnhard (1031106) | more than 3 years ago | (#34009926)

What size does a planet have to be to become a star? Is it 3 x Jupiter?

Re:Simple question... (1)

hcpxvi (773888) | more than 3 years ago | (#34009956)

What kind of a unit is Jupiter masses anyway? How much is that in Humvees?

Re:Simple question... (0)

Anonymous Coward | more than 3 years ago | (#34010004)

What kind of a unit is Jupiter masses anyway? How much is that in Humvees?

Jupiter is a pretty average gas giant and there are a fudgeload more of them in other systems. It makes sense to compare their sizes to Jupiter; apart from giving things a decent scale, it's more intelligent than saying '153.31 Earth Masses' or whatever it would be.

Speaking of which, what kind of measurement is Humvees?

Re:Simple question... (2, Informative)

beelsebob (529313) | more than 3 years ago | (#34009968)

The minimum size of a star is thought to be about 83 times the mass of jupiter.

Re:Simple question... (1)

EmagGeek (574360) | more than 3 years ago | (#34010040)

I didn't know mass was a unit of size. :p

Re:Simple question... (4, Informative)

beelsebob (529313) | more than 3 years ago | (#34010272)

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.

Re:Simple question... (1)

Surt (22457) | more than 3 years ago | (#34012466)

It is when you think about compacting it down into the smallest volume such that nuclear fusion starts up.

Re:Simple question... (1)

buchner.johannes (1139593) | more than 3 years ago | (#34010052)

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.

Re:Simple question... (1)

sznupi (719324) | more than 3 years ago | (#34010244)

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)

Re:Simple question... (1)

Geoffrey.landis (926948) | more than 3 years ago | (#34011076)

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.

Re:Simple question... (1)

sznupi (719324) | more than 3 years ago | (#34011878)

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.

Re:Simple question... (0)

Anonymous Coward | more than 3 years ago | (#34010116)

To elaborate on the correct answer of '83' above:

Up to 13 Jupiter masses is classified as a planet
Roughly 13 Jupiter masses is the minimum to be classified as a Brown Dwarf (based on the idea that this is the mass required to fuse deuterium, which brown dwarfs do before entering their cooling phase)
Roughly 83 Jupiter masses is the minimum mass for sustained hydrogen fusion, at which point it's classified as a star

Note that there is at least one object which is not quite accounted for in the current mass based definition of a Brown Dwarf. It is Cha 110913 [wikipedia.org] which appears to chemically be a brown dwarf, but may be as small as 8 Jupiter masses.

On the high end there is no discrepancy (that I'm aware of), since the sustained hydrogen fusion requirement to be considered a star is tightly tied to mass.

Re:Simple question... (1)

SharpFang (651121) | more than 3 years ago | (#34010198)

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.

Re:Simple question... (1)

Burnhard (1031106) | more than 3 years ago | (#34010408)

Yes, but I suppose I meant how much mass of gassy stuff (hydrogen mostly) in this general location would it require for it to collapse under gravity and eventually form a star. By star I mean a radiating body powered by nuclear fusion, prevented from blowing apart by the counter-acting force of gravity. I originally requested this mass in units of masses of Jupiter, given it's a lot easier to visualise than SI units. I'm guessing you can't form a star by simply twiddling the variables mass/density; you do need a certain amount of mass for the star to be viable over some period of time (let us say for the sake of argument, 1 Earth year :p).

About 50 (0)

Anonymous Coward | more than 3 years ago | (#34010352)

About 50. However, there is a large overlap and the production of the matter matters nearly as much as the mass, so you can have brown dwarfs at 20 jupiters and massive planets at 60 or more Jupiters.

Re:Simple question... (2, Informative)

gmuslera (3436) | more than 3 years ago | (#34010536)

1 x the mass of Jupiter... you just need to add enough monoliths.

Such stories are frustrating (-1, Redundant)

pablo_max (626328) | more than 3 years ago | (#34010024)

I find it frustrating that at our current rate of investment toward space exploration and science in general that I, most likely will never know the answer within my lifetime.
My father recalls as a child it was assumed we would all have experienced the glory of space travel by now.

Still, any news like this is good news. Perhaps it gives hope to the future generations whereby causing them to make an investment in mankind's future.

Re:Such stories are frustrating (1)

sznupi (719324) | more than 3 years ago | (#34010296)

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...

Navi and Ewoks breeding? (0)

Anonymous Coward | more than 3 years ago | (#34010028)

Navi and Ewoks in the same planetary system. That's some really disturbing fan and slash fiction.

Re:Navi and Ewoks breeding? (-1, Troll)

geminidomino (614729) | more than 3 years ago | (#34010648)

Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?
Hey! Listen!
Yub Yub?

*eats shotgun*

(Your comment violated the "postercomment" compression filter. Try less whitespace and/or less repetition.)

Big Just (1)

ultranova (717540) | more than 3 years ago | (#34010050)

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?

Re:Big Just (1)

BeanThere (28381) | more than 3 years ago | (#34010144)

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.

Re:Big Just (1)

prefect42 (141309) | more than 3 years ago | (#34010268)

Hot moon orbiting a cold giant sounds potentially trixy. Orbit would also be fairly important, or else you'd freeze your nuts off behind the giant.

Re:Big Just (2, Insightful)

sznupi (719324) | more than 3 years ago | (#34010318)

...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?

Re:Big Just (1)

prefect42 (141309) | more than 3 years ago | (#34010346)

But do you end up with a nice stable temperature like you would with a sphericalish orbiting body getting its heat from a star?

I know some of the volcanically active moons get crushed in different ways during their long orbits round their body, but I'd have thought that'd lead to fairly major temperature variations.

I know remarkably little about astrophysics ;)

Re:Big Just (1)

sznupi (719324) | more than 3 years ago | (#34010366)

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.

Re:Big Just (1)

prefect42 (141309) | more than 3 years ago | (#34010394)

Right. But it still makes for quite a lively surface compare to a star heated object doesn't it? A quick google suggests variation from 90-170K with small areas of volcanoes being far hotter (1500K).

Or would a larger and more atmosphered moon smooth off that variation a fair bit?

Re:Big Just (1)

sznupi (719324) | more than 3 years ago | (#34010444)

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.

Re:Big Just (1)

BeanThere (28381) | more than 3 years ago | (#34012176)

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.

Re:Big Just (1)

prefect42 (141309) | more than 3 years ago | (#34012288)

So for the non astrophysicist, how does a gas giant form that close the the star where it's "warm"?

Re:Big Just (1)

ultranova (717540) | more than 3 years ago | (#34010276)

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.

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 as the giant is. 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.

And we aren't talking about colonizing moons, we are talking about life evolving in one. So double fail on your part.

Hot Jupiters (0)

Anonymous Coward | more than 3 years ago | (#34010486)

Hot Jupiters. We have some that are in mercury-sized orbits.

Where do you and the OP get the idea that you need COLD to form a Jupiter? All you need is mass.

Re:Big Just (1)

BeanThere (28381) | more than 3 years ago | (#34012120)

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.

Re:Big Just (0)

Anonymous Coward | more than 3 years ago | (#34010322)

Of course, you could heat the environment of an already-existing gas giant, but how would that happen?

Maybe (I don't know how to verify this) if you can drop a small black hole (about the mass of our Moon) into the center of that gas giant, gas would fall in towards it, get compressed somewhere ahead of the hole's event horizon and start fusing. Radiation pressure from the fusion reaction and from the black hole itself might be enough to keep things near equilibrium for a while - keep most of the fusing gas shell (shall we call it an accretion shell?) hovering beyond the hole's static limit. It would be beautiful - a tiny black hole surrounded by a very small shell of fusing gas which heats up the rest of the gas giant. One VERY dim, VERY lightweight red dwarf, coming up.

Dunno if it's possible, though :(. Maybe I should beer-up a physics grad to run the numbers for me. It would make for a nice gimmick in a space-opera.

Re:Big Just (1)

sznupi (719324) | more than 3 years ago | (#34010478)

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)

Re:Big Just (0)

Anonymous Coward | more than 3 years ago | (#34010802)

Wow. Thanks for answering, in the first place. Us ACs aren't normally granted that courtesy.

No fusion? That's... disappointing. I was kinda hoping that the accretion shell (it can't really be a disk since there's matter falling in from all sides, unlike in a binary system of star + black hole companion) would float itself away from the black hole by "simply" trying to explode all the time. I found this [allquests.com] and I thought hey! that's interesting!

You are basically saying that all of the planet would simply fall in towards the black hole and rather quickly at that... are you sure? A very small black hole would probably add mass slower and much of the added mass would come right back out in the form of radiation.

I'd be curious about the many examples... afaik no black hole that small has ever been found.

Re:Big Just (1)

sznupi (719324) | more than 3 years ago | (#34011662)

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 mechanism which would maintain equilibrium (you miss again how the proposed "shell" wouldn't be supported on anything, would want to escape in all directions, also towards the event horizon; and why shell/disk would be different, anyway?)
But I didn't say all of the planet would simply fall in - yes, there should be also an "explosion", that's what it will make it quite bright on the scale of a galaxy; certainly nothing like in the recent Star Trek...

(to register and log in isn't much of a problem?)

We might have found Pandora? (1)

Troggie87 (1579051) | more than 3 years ago | (#34010076)

So if we launch all of our nukes now, how long would they take to get there? Goddamn furries.

Re:We might have found Pandora? (0)

Anonymous Coward | more than 3 years ago | (#34010112)

If we time it right we may have enough time to develop FTL travel, and be there to watch the explosion!

Re:We might have found Pandora? (1)

Magada (741361) | more than 3 years ago | (#34010326)

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.

Re:We might have found Pandora? (1)

sznupi (719324) | more than 3 years ago | (#34010402)

/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")

Re:We might have found Pandora? (1)

gmuslera (3436) | more than 3 years ago | (#34010568)

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.

Re:We might have found Pandora? (1)

vlm (69642) | more than 3 years ago | (#34010618)

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".

Re:We might have found Pandora? (1)

Magada (741361) | more than 3 years ago | (#34010932)

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.

Intelligent life... (2, Interesting)

Slur (61510) | more than 3 years ago | (#34010098)

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.

Re:Intelligent life... (2, Funny)

MichaelSmith (789609) | more than 3 years ago | (#34010108)

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.

Re:Intelligent life... (0)

Anonymous Coward | more than 3 years ago | (#34010384)

I'm genuinely curious: On what basis do you make this statement?

Re:Intelligent life... (1)

gman003 (1693318) | more than 3 years ago | (#34010692)

Sure - on their home turf. But they'd probably find oxygen toxic, or start overheating at -40 degrees, or something else. That's part of evolution - you can't evolve resistance or tolerance to something you are never exposed to (thus explaining why plutonium is highly toxic to humans even disregarding the radiation issues). So no need to worry about an alien invasion yet - they'd need as much equipment to survive on Earth as we would to survive on Titan.

I am an author of the study (5, Informative)

Theory of Everything (696787) | more than 3 years ago | (#34010534)

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.

Re:I am an author of the study (1)

Geoffrey.landis (926948) | more than 3 years ago | (#34011104)

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 (3, Interesting)

Theory of Everything (696787) | more than 3 years ago | (#34012152)

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? (1)

Latent Heat (558884) | more than 3 years ago | (#34011190)

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?

Re:Radiation belts? (1)

Theory of Everything (696787) | more than 3 years ago | (#34012208)

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.

Re:I am an author of the study (1)

Philomage (1851668) | more than 3 years ago | (#34012048)

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.

Re:I am an author of the study (1)

Theory of Everything (696787) | more than 3 years ago | (#34012360)

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 alternative theory.

Note that we are not claiming that the "core accretion" model does not happen in nature. Rather, it cannot be the only method by which planets form.

Orbits (4, Informative)

Hatta (162192) | more than 3 years ago | (#34010918)

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 (0)

Anonymous Coward | more than 3 years ago | (#34011264)

I am afraid you are mistaken. It is quite possible for planets to have a stable orbit (as stable as orbits get anyway) in the habitable zone of one of stars of a binary star.

Re:Orbits (3, Informative)

TheTurtlesMoves (1442727) | more than 3 years ago | (#34011360)

Check out the 3 body problem. Turns out that the only way you get long life orbit is if its orbiting just one star close enough that gravity is more or less dominated by that single object. ie to good approximation, its orbiting just one star.

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.

Trying to find other habitable planets is futile.. (1, Troll)

mark-t (151149) | more than 3 years ago | (#34012396)

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 people who might actually want to engage in such a mission? What if, when they get there, they find out it's a bust? We've sentenced generations of people to death in the blacknesss of space, with absolutely *NO* means of ever getting back within their lifetime. We could hypothetically also just send a probe, but again, the sheer magnitude of time that would elapse before a probe actually reached the destination could make it unlikely that any people are actually still listening for the probe to send back any data.

As I see it, scouting around the galaxy for exoplanets that can possibly host life when we don't have the technology to send anything there within a time frame that is reasonable for the purposes of what would have to be just an experiment, is one of the hugest wastes of time and resources that I can imagine.

Now I've heard the arguments that living only on this planet, we *do* have all of our eggs in one basket, and it wouldn't take very much to wipe us out. These arguments are not wholly lost on me, but I can't see sending people to a place so far away that meaningful communication is not just impossible because of limitations on technology, but impossible because of physical constraints on the operation of the universe itself, is going to help matters... the time scales involved are so insanely large that it's unlikely in the extreme that anyone on earth around the time of its predicted arrival would even know or care if the vessel actually reached its destination at the scheduled time. We could not have any comfort that we might endure beyond a global catastrophe because there would be no way to ever know. That said, of course... it's not impossible for people to receive comfort from believing in things that aren't necessarily true, but that's not very scientifically valid is it? It's hardly any sort of real solution to the problem that we are likely to all be wiped out if we stay here when we subject parts of our population to even greater risks just by propelling them off this rock at the greatest velocities that are physically achievable by technology that we have with not even the slightest hope of ever returning.

Now that said, if we could find a way to extend productive and healthy human life to be at least a couple of orders of magnitude larger than how long we have it currently, well then, sending people to other stars might become a viable thing to do. Or, even more unlikely (IMO), if we find a way to break the speed limit that the universe has imposed on absolutely every single thing that exists, then I could see finding habitable exoplanets possibly being something of promise... and of hope. Until then, however, I'm afraid I really just don't see the point.

Okay... I'm done. Mod away.

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