Pale Red *Dots* ESO | Proxima b confirmed UPDATE 2017 PaleRedDots!!

[fredinno]

43 minutes ago, PB666 said:

Quite impossible its the n-body problem in spades. A planet would have to orbit between AB and P to be in a stable orbit. IOW it would have to be so far from B at B's apoapsis and planets periapsis that perturbations by B were trivial. Run an N-body dynamic for any orbit that does not fry life around A and B and follow it for say 1000 B orbits. Bs mass is about 80% of A so any planet X would not want an orbit where at perialpha  is 11.2 AU/2. That orbit immediately throws X into a death or exit orbit. So luminosity of A is 1.5 Sol which means X has to be 1.5AU from alpha. 

This places X in a orbit between 1.5 and 5.5 AU, but the problem is that for many passes of B as B approaches peri, X is eventually lifted up into a eccentric orbit until B recedes, moreover if Bs plane and Xs inclination are not spot on B will send X into a wildly eccentric orbit. As B passes in its 70 year orbit it will spend about 15 years at a proximity to A that it can seriously affecting the orbit of X

Lets take an example suppose B is currently close to minimum of A say 15' from the minimum theta in its orbit, its about 14 AU away, X is traveling around A at 1.5 AU and is now traveling directly toward B in its orbit this means its got about 3 months till it achieves the minimum distance from B. So the pull of A is its M (1.1x *k /(1.5)^2) the pull of B is (0.9 * k /  (14) ^2). Lets say the stars gravity is 0.002 at that point. Looks bad but watch out, X now begins to acceleration toward B at 10-5 N/Kg. Not bad until you consider there are 100,000 secs in a day and you have 90 days, worse that the distance between B and X is going to close down. The orbital response of X is to travel outward and slow down, but Bs pull will not subside because A has to make several passes, its not until B is moving away from A that the process reverses somewhat, but by that time all niche selection on X is gone, habitats are gone, its evolution killed.

....No, it can orbit within the SOI of either star, and orbit it at 1 AU, not orbiting both stars.

[PB666]

34 minutes ago, fredinno said:

....No, it can orbit within the SOI of either star, and orbit it at 1 AU, not orbiting both stars.

You didn't read, just because it orbits a its attracted to B, once it achieve a apoapsis of 6AU it can be pulled from A to B but since A/B are pulling equally it will simply be ejected.

There may be a moment in which X is in a habitable zone, but that moment would not last long enough for the appreciable advancement of life. You can have stable orbits very close to A and to B but not orbits that are say 1/10th as close to B as they are to A if B and A are approximately the same size.

Quote

Wikipedia- . In reality, some orbital ranges are impossible for dynamical reasons (the planet would be expelled from its orbit relatively quickly, being either ejected from the system altogether or transferred to a more inner or outer orbital range), whilst other orbits present serious challenges for eventual biospheres because of likely extreme variations in surface temperature during different parts of the orbit. Planets that orbit just one star in a binary system are said to have "S-type" orbits, whereas those that orbit around both stars have "P-type" or "circumbinary" orbits. It is estimated that 50–60% of binary systems are capable of supporting habitable terrestrial planets within stable orbital ranges.^[69]

Having and sustaining habitable zones are two different things. Track an orbit see what happens.

Quote

Early computer-generated models of planetary formation predicted the existence of terrestrial planets around both Alpha Centauri A and B,^[94][97][98] but most recent numerical investigations have shown that the gravitational pull of the companion star renders the accretion of planets very difficult.^[93][99] Despite these difficulties, given the similarities to the Sun in spectral types, star type, age and probable stability of the orbits, it has been suggested that this stellar system could hold one of the best possibilities for harbouring extraterrestrial life on a potential planet.^{[6][85][100][101]}

Two disparaging results take the most conservative.

Edited March 25, 2016 by PB666

[fredinno]

55 minutes ago, PB666 said:

1 hour ago, fredinno said:

 

You didn't read, just because it orbits a its attracted to B, once it achieve a apoapsis of 6AU it can be pulled from A to B but since A/B are pulling equally it will simply be ejected.

There may be a moment in which X is in a habitable zone, but that moment would not last long enough for the appreciable advancement of life. You can have stable orbits very close to A and to B but not orbits that are say 1/10th as close to B as they are to A if B and A are approximately the same size.

They're not really similar size, A is ~110% solar mass and B is ~90% solar mass.

Also, your Wiki quote states the orbits are stable, but that formation is difficult, so it's a possibility. B is a K2-type star, so it can host a desert planet much closer to its star. B can support a Earth-like planet at 0.7-8 AU. http://astro.unl.edu/naap/habitablezones/animations/stellarHabitableZone.html

[PB666]

1 hour ago, fredinno said:

They're not really similar size, A is ~110% solar mass and B is ~90% solar mass.

Also, your Wiki quote states the orbits are stable, but that formation is difficult, so it's a possibility. B is a K2-type star, so it can host a desert planet much closer to its star. B can support a Earth-like planet at 0.7-8 AU. http://astro.unl.edu/naap/habitablezones/animations/stellarHabitableZone.html

Those people who suggest alpha centauri can support life are, simply stated, way too optimistic, sure it would be nice that the closest star can support a space colony, but i think any sensible space traveler would think, ther but by the grace of god there go i. I would be seriously surprised if there was any planet between a 1 unit and b  1 unit. there size diiference is 0.81, which basically means things need only get close to the mid zone and n-body physics takes over, its a no brainer those satellites are either toast or intestellar objects. Proxima centauri would be a decent target because its possible to do searches for bodies that are in dark orbits that you could probably land and exploit, which is really what is needed. 

Edited March 26, 2016 by PB666

[Spaceception]

Just now, PB666 said:

Those people who suggest alpha centauri can support life are simply staed way too optimistic, sure it would be nice that the clsestvstar can support a space colony, but i think any sensible space traveler would think, ther but by the grace of god there go i. I would be seriously surprised if there was any planet between a 1 unit and b  1 unit. there size diiference is 0.81, which basically means things need only get close to the mid zone and n-body physics takes over, its a no brainer those satellites are either toast or intestellar objects. 

@fredinno

 

Alright, I think this has gone on long enough, take it to a new topic please, this is talking about finding planets around Proxima Centauri, not talking about the stability of the habitable zones around Alpha Centauri A//B, I don't want this thread closed for going off topic, especially since we're probably 2 to 4 months away from potentially talking about a solar system ESO Astronomers have found, Okay? Okay.

[ProtoJeb21]

I don't care what planet we find around Proxima. Heck, I'll even CELEBRATE the discovery of a hot jupiter around that star! It would be a great opportunity to study those freaks of nature close-up with our current technology. And, if a planet is orbiting far away enough, we could find its MOONS.

[fredinno]

2 hours ago, PB666 said:

Those people who suggest alpha centauri can support life are, simply stated, way too optimistic, sure it would be nice that the closest star can support a space colony, but i think any sensible space traveler would think, ther but by the grace of god there go i. I would be seriously surprised if there was any planet between a 1 unit and b  1 unit. there size diiference is 0.81, which basically means things need only get close to the mid zone and n-body physics takes over, its a no brainer those satellites are either toast or intestellar objects. Proxima centauri would be a decent target because its possible to do searches for bodies that are in dark orbits that you could probably land and exploit, which is really what is needed. 

It's less optimistic than Elon is on a day-to day basis

[Spaceception]

Proxima Centauri by 2099?

http://www.aerospaceamerica.org/Documents/Aerospace_America_PDFs_2016/April2016/Feature1_Proxima_AA_April2016.pdf

[PB666]

47 minutes ago, Spaceception said:

Proxima Centauri by 2099?

http://www.aerospaceamerica.org/Documents/Aerospace_America_PDFs_2016/April2016/Feature1_Proxima_AA_April2016.pdf

The only problem with that big foil plate ousing a coke can that weighs as much as a paper clip and sees all knows all and transmits all back to earth.........The laser energy he proposes on occassion would destroy the big foil plate. Second tracking, you arrays are gathering juice from near sun orbit,mthey are in orbit about the sun, how do they track a plate so small that even hubble could not see it. 

[fredinno]

23 hours ago, PB666 said:

The only problem with that big foil plate ousing a coke can that weighs as much as a paper clip and sees all knows all and transmits all back to earth.........The laser energy he proposes on occassion would destroy the big foil plate. Second tracking, you arrays are gathering juice from near sun orbit,mthey are in orbit about the sun, how do they track a plate so small that even hubble could not see it. 

I might see the innovate interstellar explorer + a mission to Eris by the same probe by 2099, but not an Alpha Centauri probe. That would need tech too extensive for the next century.

https://en.wikipedia.org/wiki/Innovative_Interstellar_Explorer

Edited April 7, 2016 by fredinno

[Spaceception]

YES!!!!!

At the end of August, ESO will formally annouce an Exoplanet, potentially habitable, around Proxima.

 

WHOO!

http://www.seeker.com/new-nearby-earth-like-planet-discovered-1970197349.html

[StrandedonEarth]

2 hours ago, Spaceception said:

YES!!!!!

At the end of August, ESO will formally annouce an Exoplanet, potentially habitable, around Proxima.

 

WHOO!

http://www.seeker.com/new-nearby-earth-like-planet-discovered-1970197349.html

Woohoo! And we shall name it "Wunderland"!

[_Augustus_]

YAYAYAYAYAYAYAYAYA! Now we must beam our TV signals at it!

[ProtoJeb21]

If there is an intelligent civilization around Proxima, then they've been watching our sitcoms for the last 80+ years. We can probably communicate with them an form an alliance. How cool would it be for members of each civilization, ours and Proxima's, to be visiting each other's solar systems?

[Mitchz95]

Let's hope it's not Trisolaris...

Edited August 15, 2016 by Mitchz95

[SargeRho]

8 hours ago, ProtoJeb21 said:

If there is an intelligent civilization around Proxima, then they've been watching our sitcoms for the last 80+ years. We can probably communicate with them an form an alliance. How cool would it be for members of each civilization, ours and Proxima's, to be visiting each other's solar systems?

Actually, I read that our radio "bleed" is undetectable after 2-3 light years, due to becoming indistinguishable from background noise. I'm not sure how much that applies to targeted transmissions though.

[ProtoJeb21]

47 minutes ago, SargeRho said:

Actually, I read that our radio "bleed" is undetectable after 2-3 light years, due to becoming indistinguishable from background noise. I'm not sure how much that applies to targeted transmissions though.

I guess that may be a good thing, since they may get some "inspiration" on how to introduce themselves from Jack Nicholson's character in The Shining. That would scare the core out of our planet, and everyone who witnesses it.

[magnemoe]

37 minutes ago, SargeRho said:

Actually, I read that our radio "bleed" is undetectable after 2-3 light years, due to becoming indistinguishable from background noise. I'm not sure how much that applies to targeted transmissions though.

Targeted signals is targeted against places on earth or in orbit and the earth rotates so you would just get fragments, targeted signals is also weaker than the high power broadcast ones. Radars is high powered but carry no signal. 
My guess is that we would know if it was an civilization around Proxima if we listened for an good time, you might have to listen for weeks for an targeted signal going in out direction. 

 

[Streetwind]

On 13.8.2016 at 4:50 AM, StrandedonEarth said:

Woohoo! And we shall name it "Wunderland"!

Let's not go begging for a catpeople invasion, shall we?

[Emperor of the Titan Squid]

Woohoo! Let's start sending signals and launch a probe ! I say we add laser sails, a VASIMR drive, and an Orion drive. Begin colonizing the moon, Mars, Venus, deep space, orbit, asteroids, and everything else. Build star ports! Build propellant depots! Build orbital construction and logistics bases! Destroy the outer space treaty! Build spaceplanes, HLVs and RLVs! Mine the asteroids! Create space fountains  and space elavators! I am excited to see what this planet is like. If only it has a magnetic field . . .

Edited August 15, 2016 by Emperor of the Titan Squid

[_Augustus_]

10 hours ago, SargeRho said:

Actually, I read that our radio "bleed" is undetectable after 2-3 light years, due to becoming indistinguishable from background noise. I'm not sure how much that applies to targeted transmissions though.

No, in theory it could stretch as far as 5 light-years.

Unfortunately, the first things they'd see would be the 1938 Olympics in Berlin, followed by World War II and the Cold War.

[Emperor of the Titan Squid]

We should send probes to alpha Centauri too, to make sure that there are no planets to destroy earth to make way for a hyperspace bypass, and make sure that the Fithp don't invade. How close is Proxima Centauri's habitable zone to itself? 

Edited August 15, 2016 by Emperor of the Titan Squid

[magnemoe]

9 hours ago, _Augustus_ said:

No, in theory it could stretch as far as 5 light-years.

Unfortunately, the first things they'd see would be the 1938 Olympics in Berlin, followed by World War II and the Cold War.

However even if the signal to noise level is not an issue I think the radio telescope able to pick up the 1938 broadcast would have been so big as an small planet. 
More so an advanced civilization would know it was life on Earth this is far easier to spot, in short they would be here first. 
 
So an advanced civilization is unlikely but we can always hope for catgirls in fur bikinis

Edited August 15, 2016 by magnemoe

[Spaceception]

Just now, Emperor of the Titan Squid said:

 How close is Proxima Centauri's habitable zone to itself? 

6 to 28 days I believe.

[Spaceception]

Proxima Centauri is trending #1 on Facebook.