What if Alpha Centauri has no planets?

[Wodan]

Very doubtful that a gas giant so large would form so close to the system's star.

...leaving that aside for a moment....

A binary star system is where two stars are close together closer then Mercury is to the sun.

What's your basis for this definition?

Note that, by this definition, Alpha Centauri does not qualify. The two larger components are 23 AU apart.

Correction to Acal and Wodan:

Centauri system is actually a trinary system : Alpha A and Alpha B act pretty much like a binary system and Proxima centauri orbits around the center of gravity of A-B binomium....

Not that I'm seeing a Earth-like system in the middle of this mess... it is just too chaotic.

"Binary system" is generally accepted to mean any system with more than one stellar mass. "Trinary" would be more accurate in this case, of course.

Aside, here is a discussion of planetary formation in binary systems.

And here is an actual discovery of a planet around a binary star.

And here is a paper about planets around Alpha Centauri.

Wodan

 

[r_rolo1]

I know that a rocky planet could form easily orbiting either Alpha Centauri A or B in the habitable zone in a stable fashion ( or even around C ( Proxima )). But it would be a earth like planet? First the tidal forces would be strong and probably would destabize any moon ( that is widely known that deflects a lot of harmful objects from Earth ). Alpha centauri system also does not show signs of Comets or of any Oort like area.... (I would be surprised if it had it, because of the destabilizing effect of Proxima ) This may mean that water is scarce out there .

Proxima in fact may be a better candidate for a earth like planet, if we discount the flares and the fact that the rotation of that planet would be stopped due to the proximity of the red dwarf......

 

[Magma_Dragoon]

The moon stabalizes the tilt of the Earth, maybe you are thinking of that? I would point out that we can't even see our own Oort cloud. Also, something very interesting happens to a watery planet tidally locked to a red dwarf: an enormous and permanent hurricane. Pretty neat, huh?

 

[Magma_Dragoon]

Very doubtful that a gas giant so large would form so close to the system's star. A binary star system is where two stars are close together closer then Mercury is to the sun.

No, its not.

 

[r_rolo1]

The moon stabalizes the tilt of the Earth, maybe you are thinking of that? I would point out that we can't even see our own Oort cloud. Also, something very interesting happens to a watery planet tidally locked to a red dwarf: an enormous and permanent hurricane. Pretty neat, huh?

1 No, I was thinking in the efect that moon gravity has in the orbits of near-Earth objects... but good call on the axis tilt.

2 We can't see our own Orrt cloud, but we can see comets, can't we? Comets in a 4 light-years away star should be easily detectable ( even by spectrometrical measures of the light of the stars ( a sudden increase in the oxygen and carbon lines would be a sure sign of a comet passing by ) ) and AFAIK none was detected so far. Because of that some suspect that Alpha centauri A-B binary should be pretty poor in water. If that means that a watery planet is imposssible in there... not sure, but they seem less likely than in the Sun's orbit ( were there are a handful of objects bigger than Pluto with lots of water: Earth Mars, Europa,..... )

3 And you forgot the equally huge anticiclone in the other side of the red dwarf planet and the massive winds between both

 

[Willem]

Also, something very interesting happens to a watery planet tidally locked to a red dwarf: an enormous and permanent hurricane.

And how would we know that since ours is the only watery planet we know of?

 

[Magma_Dragoon]

Computer simulation I saw on the Discovery Channel.

 

[Willem]

Computer simulation I saw on the Discovery Channel.

Which makes it sheer speculation not based on fact. Reality may turn up something completely different. We can barely map out our own climate using computer models, never mind some imaginary planet we haven't even discovered yet.

 

[r_rolo1]

Well, the atmosphere of hypotetical red dwarf terrestial planet is far more simpler to compute than ours because the planet does not rotate, due to the grav forces of the star ( red dwarfes are very dim and a planet to have liquid water would need to be very close of the star ). This means:
-No colirois forces ... wind will flow straight, unlike earth
-Only one hot area ( the one directly facing the Star ) and only one cold area ( the one that never catches light from the star )

Those 2 together create a very simple weather system: one huge low pression area in the side facing the star and one huge high pressure area exactly in the antipodes. This would create strong surface winds from the cold area, hence cold as hell.....

Basically that world would have a giant hurricane, a huge Antartica style area in the exact antipode and strong and glaciar winds in between. Not cozy at all.... but probably bearable

 

[Magma_Dragoon]

Don't forget the eternal twilight around the edges. How awesome would that be? Definitely hospitable to me, and exciting. I think I'll purchase a summer home on Proxima Prime.

 

[blackrabbit]

Negator_UK,

Believe it or not, this is something that has happened more than once in human history. Humans have always been fascinated with the unknown, and have gone through great peril to travel somewhere new. Often times ending up worse off than they were, or possibly dead. One excellent example that most of us computer gamers know about is The Oregon Trail. It was a very fun game where you had to manage a family trying to immigrate to Oregon via wagon and all the hardships that came along with it. It became sort of an internet meme not too far back, and spawned this shirt:

As funny as it is, it is also true to life. Many people travelling along the Oregon Trail died.

Also Magellan was given credit for the first single voyage circumnavigation of the globe (they named the small body of water where South America and Antartica are the closest the Straights of Magellan.) However did you know that while his ship circumnavigated the globe, he did not? Magellan died before the trip was complete, but his crew sailed on.

So while you are trying to invoke some humour into the situation, your kinda stumbled into an excellent point. Often times humans spend enormious amounts of money, and sometimes their lives, for something that doesn't exst or something futile.

Another great example is Mars. We've all been speculating that there might be life on mars. Well we sent many devices up there only to find out that there is no life. How? Many of these devices had/have some sort of scanning device that can scan for life in one way or another. We came up empty. Our desire to not be alone in the immediate universe caused us to waste tons of money on a device to search for life where there is none. And don't think we won't do it again! Titan, Jupiter's largest moon, is next. Now that the whole "Mars has life!" fiasco is dead (sorry for the bad pun ) people have moved onto "Titan has life!"

My point is, humans waste a lot of resources, including our own lives, on silly things. But that's our nature; to seek out and explore that which we don't know. Often times that means doing something wrong 100 times so we can discover 100 ways to not do something.

My sister always died in Oregon Trail

 

[amazingorange]

I think that there is no life on other planets, so this is all a huge waste of time. Its still fun to talk about, but I dont think there is life on other planets.

 

[Wodan]

I think that there is no life on other planets, so this is all a huge waste of time.

Even if there's no life, that's not to say there aren't planets that can support terrestrial life.

In any event, you could be wrong. This would be called "contingency planning".

Wodan

 

[amazingorange]

Even if there's no life, that's not to say there aren't planets that can support terrestrial life.

In any event, you could be wrong. This would be called "contingency planning".

Wodan

I sort of forgot about the whole idea of living on other planets, I think that is a good idea to plan for, so I guess its not totally pointless.

And if I am wrong, may I be wrong in Heaven instead of still here on earth when everyone freaks out about an alien invasion or whatever.

 

[Willem]

I think that there is no life on other planets, so this is all a huge waste of time. Its still fun to talk about, but I dont think there is life on other planets.

With the billions of planets orbiting the billions of stars in the universe, the odds that we are the only one with life is pretty astronomical. Making a statement like yours is kind of like the old idea that the universe revolved around Earth. I doubt intelligent life is all that common but there's certainly a planet somewhere that has a functioning ecosystem. Even if the odds are one in a billion, that will still leave millions of possibilities.

 

[amazingorange]

I have to base my beliefs about life on other planets on what the bible has to say about it, and it is not mentioned anywhere in the bible and I dont think that God created life on other planets. It says in the bible that earth was created first, on day one, and the sun and the moon as we know them were created on day four along with the stars, so creation sort of got center stage here on earth. The lights out there in the sky were created to both demonstrate the amazing power of God and to mark seasons and days and years, not to house more creations that God made, as I see it anyway.

So there you have my view.

 

[Willem]

Like I said, making a statement like yours is kind of like the old idea that the universe revolved around Earth. The old theologians used the same argument as yours to discredit Copernicus, and guess who was right? It's a rather ethnocentric view that we have sole access to God. The bible doesn't say anything about Quantum Physics or nuclear fusion either, does that mean they don't exist as well? You can believe what you want to, but to many of us discussions like this are not a waste of time.

 

[Magma_Dragoon]

That is a narrow vision of God, and makes him small. I believe God has the power to make a universe which is vast beyond our feeble ability to comprehend, and brimming with an infinite diversity of beautiful living creatures.

You might catch some flak for saying something as medeival as that, but what I just said is probably what those people are trying to say. As much as I'd like to argue about theology, lets try to keep it out of this thread, or the mods will probably close it.

 

[amazingorange]

You guys have made me do some research and have I have been led to some interesting conclusions and learned some new things that actually changed my outlook on the universe, but as Magma Dragoon mentioned, we should probably keep this out of the thread. Interesting stuff though!

 

[brades]

I have to base my beliefs about life on other planets on what the bible has to say about it, and it is not mentioned anywhere in the bible and I dont think that God created life on other planets. It says in the bible that earth was created first, on day one, and the sun and the moon as we know them were created on day four along with the stars, so creation sort of got center stage here on earth. The lights out there in the sky were created to both demonstrate the amazing power of God and to mark seasons and days and years, not to house more creations that God made, as I see it anyway.

So there you have my view.

In a scientific discussion, or at least semi-scientific speculation there is no place for the Bible.