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

[peadar1987]

 

2 hours ago, kurja said:

But it would also need to rotate..?

Yeah, it would. Tidal locking is the biggest problem here, not lack of a moon

 

1 hour ago, Bill Phil said:

In the case of planets, yes. Gas Giant moons, however... Well, how else do you think Europa is warm enough?

Well yes, but that's not what the situation is here. This new planet orbits at 0.05AU. Europa orbits at about 0.003AU. There's an order of magnitude in the difference

 

[Bill Phil]

Just now, peadar1987 said:

 

Well yes, but that's not what the situation is here. This new planet orbits at 0.05AU. Europa orbits at about 0.003AU. There's an order of magnitude in the difference

 

But there's also an (a few?) order of magnitudes of difference in the mass of the parent.

[peadar1987]

Just now, Bill Phil said:

But there's also an (a few?) order of magnitudes of difference in the mass of the parent.

As I understand it, the heating is caused by the eccentricity of the orbit, and the orbital period. The mass of the planet isn't included in the equation

[Bill Phil]

Just now, peadar1987 said:

As I understand it, the heating is caused by the eccentricity of the orbit, and the orbital period. The mass of the planet isn't included in the equation

Yeah... But there's likely to be some tidal heating.

[Spaceception]

5 hours ago, Scotius said:

This planet is orbiting too close to the star to have a sizeable moon. No moon to keep the inner core dynamo turning, means no magnetic field. No magnetic field means less protection from already increased amounts of radiation coming from the star. I don't have much hope for Proxima b to be anything more than a sterile barren desert. Maybe, if there are sizeable bodies of water life appeared under the surface, where radiation is not a threat.

Not necessarily, Mercury has a weak magnetic field, but no Moon.

So I guess we just have to wait and see, more reason to fund Starshot, right?

[peadar1987]

29 minutes ago, Bill Phil said:

Yeah... But there's likely to be some tidal heating.

Of course, but the dominant factors are going to be primordial heat and radioactive decay. My original post was a reply to someone saying that this planet wouldn't have a magnetic field, because it wouldn't have a moon to create an internal dynamo, I was just pointing out that a moon isn't necessary for that (although I suspect Earth's primordial energy was significantly "topped up" in its collision with Theia to form the moon, which won't have hurt)

[Bill Phil]

Just now, peadar1987 said:

Of course, but the dominant factors are going to be primordial heat and radioactive decay. My original post was a reply to someone saying that this planet wouldn't have a magnetic field, because it wouldn't have a moon to create an internal dynamo, I was just pointing out that a moon isn't necessary for that (although I suspect Earth's primordial energy was significantly "topped up" in its collision with Theia to form the moon, which won't have hurt)

Those do tend to be dominant factors.

[Spaceception]

Okay, okay, now the real question arises.

 

Who's going to make this system in KSP?

[Spaceception]

https://planetplanet.net/2016/08/24/the-eyeball-planet-next-door-a-proxima-poem/

This is pretty cool

[Mitchz95]

8 hours ago, Kryten said:

Not a chance, Hubble's angular resolution is far too low to see the planet as separate from Proxima.

Would the Webb be able to see it?

[Vanamonde]

Overlapping threads have been merged. 

[Shpaget]

2 hours ago, Mitchz95 said:

Would the Webb be able to see it?

No. JWST has about the same resolution as Hubble (~0.1 arcsec).

Proxima b and Proxima Centauri are separated about 0.036 arcsec.

[Francois424]

If anything this might make science progress in a worthy direction for space flight.

We've been sitting on our backsides since the Apollo program was canned (excluding the shuttles and LEO projects).  I've enjoyed the probes and super-telescope discoveries, but Back in '86 when I was 10, I was sure we'd be on Mars by now, heck, maybe starting the exploration of Jupiter...  Not still sending probes.  What we learn sending these "super probes" to Proxyma/Alpha Centauri should really help us getting on with space exploration.  If there is a god in this universe, I hope s/he makes that new planet a real earth-2 and provoke us to get there asap.

 

But regardless this is great news, the best since Gliese 581 (and the fabled "Zarmina's world" which could never be proven).  Far better news than "Habitable planets" 1000+ LY away (yeah, GL getting there).

[Streetwind]

55 minutes ago, Francois424 said:

But regardless this is great news, the best since Gliese 581 (and the fabled "Zarmina's world" which could never be proven).  Far better news than "Habitable planets" 1000+ LY away (yeah, GL getting there).

That's a bit unfair. The planets we've found so far are mostly so far away because the Kepler Space Telescope is (by design) only able to properly work above a certain distance, looking at small patches of sky quite far away. And the vast majority of planets we know come from Kepler. By contrast, we simply haven't looked all that closely at our more immediate stellar neighbourhood. Ground-based telescopes have found a decent number, but that's just a tiny sliver of what's nearby. We'll need a dedicated space telescope that's designed to look at nearby stars.

Coincidentally, we're getting one within the next two years: the Transiting Exoplanet Survey Satellite (TESS). It will not catch every star system nearby - some stars will simply be too dim - but in contrast to Kepler's narrow field of view, this one will be an all-sky survey. It'll be scanning the entirety of the stellar neighbourhood, in all directions. It's projected to examine over 200,000 nearby star systems this way, over a span of two years. They expect to find a minimum of 1,500 planets during that time, likely more, with a minimum of 500 rocky ones. So if you're interested in nearby planets, this is the mission you should keep your eyes on.

TESS launches December 2017, so less than 1.5 years from now.

Edited August 25, 2016 by Streetwind

[K^2]

12 hours ago, kurja said:

But it would also need to rotate..?

Convection can also result in magnetic dynamo, as far as anyone understands it. Of course, rotation helps craft a neat dipole field. Mag field of a tidally locked planet is likely to be weaker and potentially multipole, which can result in gaps in magnetic shield.

Of course, all this really means is that complex land life is unlikely, which is already the case from increased UV, really crappy weather, etc. On the plus side, if Proxima b has oceans, there could still be complex marine life. Something simple, with high rad resistance near the top collecting sunlight, more interesting things deeper under water, protected by the best natural radiation shield there is.

[Green Baron]

56 minutes ago, K^2 said:

 

Of course, all this really means is that complex land life is unlikely, which is already the case from increased UV

According to the paper the planet is most likely dry and exposed to X-rays 400 times the strength of earth. Particles from the star would probably have blown any atmospheric gases away.

Interesting is that the planet could not have formed from a planetary disc, its mass is too high, there wasn't enough material so close to the star. Could be a caught traveller or formed from planetesimals farther out and moved in.

Also i have to ask how they inferred the mass of the planet as they cannot know the tilt of the ecliptic plane. But maybe i just haven't understood the method. New instruments might reveal more in the future.

 

I must add: i am in no social network and not as exposed to the "hype" and speculation and thus may seem a little "behind the moon" to those who mainly rely on social networks and online-magazines. I have to live with that :-)

 

 

Edit: nevermind, i got that mass thing.

Edited August 25, 2016 by Green Baron

[kerbiloid]

43 minutes ago, Green Baron said:

Interesting is that the planet could not have formed from a planetary disc, its mass is too high, there wasn't enough material so close to the star. Could be a caught traveller or formed from planetesimals farther out and moved in.

Btw, whether A, B and Proxima had formed together or captured each other.
If the former, it could steal a planet in their early days. In the latter, maybe too.

Edited August 25, 2016 by kerbiloid

[Kryten]

10 hours ago, Mitchz95 said:

Would the Webb be able to see it?

No, you need something much bigger; Some of the big ground-based interferometry projects might be able to do it. There probably will be nearby exoplanets JWST can resolve, the small separation in this case just makes it particularly difficult.

[ProtoJeb21]

I never though I would say this about a Habitable Zone exoplanet....but I hope Proxima b is tidally locked.

Why?

The highest eccentricity value for Proxima b (which I've nicknamed "Feronia") is around 0.35, higher than that of Mercury. This will not make the planet tidally locked. A planet so close to its star with such a high eccentricity value would cause intense tidal heating. Feronia would be rendered not just uninhabitable, but also a volcanic planet like Mustafar. Another issue with high eccentricities is the 3:2 resonance between rotation period and orbital period. Tidal locking gives Feronia a rotation period of 11.186 days. A 3:2 resonance, like with Mercury, will give it a rotation period of at least 16.779 days. The quickest rotation period would generate a more powerful magnetic field around Feroinia, increasing chances for habitability.

If Feronia is tidally locked, life wouldn't be impossible. Plant life would be easy to adapt on Feronia, where they will just have to point in the same direction. 3:2-resonant rotation would be less favorable for plants. Not only that, but bizarre forms of life would prefer an exposure to X-Rays and UV light. Check out this cool article:

http://gizmodo.com/how-life-could-survive-on-proxima-b-1785548877

A shorter rotation period caused by tidal locking will be a bit more favorable to life, an maybe even Earth life too. The tidal locking of Feronia may not be as bad as some people think. If you look at where Feronia is around Proxima Centauri, it is in a region where materials like iron and nickel will be more abundant than where Earth formed around the Sun. Feronia could've formed with a large iron core, maybe 40-50% the volume of the planet. That would cause higher gravity, sure, but the magnetic field of the planet would be stronger. 

Feronia's formation region not only could contain lots of iron, but also lots of H/He gases. Even though that could make the planet a gas dwarf, other possible planets in the system could have shoved in different materials from farther out or could've eaten most of the gases. Also, the radiation that Feronia gets may have stripped off most of its primordial atmosphere. My best guess is that Feronia has an atmosphere between 0.5 and 5 times the pressure of Earth's atmosphere, with more H/He than Earth has but still small enough to keep it habitable.

[Shpaget]

6 hours ago, K^2 said:

Of course, all this really means is that complex land life is unlikely, which is already the case from increased UV, really crappy weather, etc. On the plus side, if Proxima b has oceans, there could still be complex marine life. Something simple, with high rad resistance near the top collecting sunlight, more interesting things deeper under water, protected by the best natural radiation shield there is.

This sort of discussion always brings up a certain thought in my head.

Assuming a marine life with DNA or similar structure, would it be such a stretch of imagination to assume the possibility of evolution to stumble upon an exceptionally robust DNA fixing mechanism? A life form that occupies shallow waters and over generations spreads to intertidal regions and eventually land would experience gradually stronger radiation. Over multiple generations it is plausible that a very strong DNA repairing mechanism emerges. Such organism would have no or little problem with existing levels and types of radiation.

[Green Baron]

@Shpaget: Too strong fixing and there's no evolution ... which means a simple change in the environment kills them all. Evolution is about variation (and selection).

@ProtoJeb21: A planetary magnetic field is not correlated with rotation or the amount of iron in a core. See the gas giants. From the paper: Proxima B ist probably locked. Also the 0,35 ecc. is a statistical figure, no fixed measurement, it may be less.

Inventing life forms on paper is surely fun but science fiction. From the paper: Equilibrium temp. of Proxima B is -39° Celsius. It would need a special greenhouse atmosphere (stronger than earth) to keep liquid water. But atmospheric gases are probably gone. Water, if it was present at all, was probably lost during the first few hundred million years.

I'd suggest we (or whoever feels entitled) take a look at Mars and Europa first ...

 

Edited August 25, 2016 by Green Baron

[CptRichardson]

23 hours ago, Kryten said:

Not a chance, Hubble's angular resolution is far too low to see the planet as separate from Proxima.

Don't need to get a seperation of imagery. We've been able to glean atmospheric data from planets without doing so before thanks to spectrally analyzing the star during transits to detect the elements associated with the planet. If any part of the planet transits, we should be able to get atmospheric data with a concentrated hubble campeign, and if not then Hubble will be better able to constrain the orbital characteristics, mass, and other properties of the planet.

[Spaceception]

6 hours ago, ProtoJeb21 said:

I never though I would say this about a Habitable Zone exoplanet....but I hope Proxima b is tidally locked.

Why?

The highest eccentricity value for Proxima b (which I've nicknamed "Feronia") is around 0.35, higher than that of Mercury. This will not make the planet tidally locked. A planet so close to its star with such a high eccentricity value would cause intense tidal heating. Feronia would be rendered not just uninhabitable, but also a volcanic planet like Mustafar. Another issue with high eccentricities is the 3:2 resonance between rotation period and orbital period. Tidal locking gives Feronia a rotation period of 11.186 days. A 3:2 resonance, like with Mercury, will give it a rotation period of at least 16.779 days. The quickest rotation period would generate a more powerful magnetic field around Feroinia, increasing chances for habitability.

If Feronia is tidally locked, life wouldn't be impossible. Plant life would be easy to adapt on Feronia, where they will just have to point in the same direction. 3:2-resonant rotation would be less favorable for plants. Not only that, but bizarre forms of life would prefer an exposure to X-Rays and UV light. Check out this cool article:

http://gizmodo.com/how-life-could-survive-on-proxima-b-1785548877

A shorter rotation period caused by tidal locking will be a bit more favorable to life, an maybe even Earth life too. The tidal locking of Feronia may not be as bad as some people think. If you look at where Feronia is around Proxima Centauri, it is in a region where materials like iron and nickel will be more abundant than where Earth formed around the Sun. Feronia could've formed with a large iron core, maybe 40-50% the volume of the planet. That would cause higher gravity, sure, but the magnetic field of the planet would be stronger. 

Feronia's formation region not only could contain lots of iron, but also lots of H/He gases. Even though that could make the planet a gas dwarf, other possible planets in the system could have shoved in different materials from farther out or could've eaten most of the gases. Also, the radiation that Feronia gets may have stripped off most of its primordial atmosphere. My best guess is that Feronia has an atmosphere between 0.5 and 5 times the pressure of Earth's atmosphere, with more H/He than Earth has but still small enough to keep it habitable.

I thought scientists made a climate model for Prox b and found a 3:2 resonance would be good, since it would distribute heat all over the planet, slower than Earth, but still good, in fact, I've already thought of a possible climate regarding this resonance for my book.

Anyway, if it's that bad, what's the minimum eccentricity for Prox b that would give it a 3:2 resonance, but would still be able to support life?

 

Also, what were the odds we'd find an Earthsized planet getting almost the same amount of light as Earth, around the closest star other than the Sun?

Edited August 25, 2016 by Spaceception

[Shpaget]

8 minutes ago, Spaceception said:

Also, what were the odds we'd find an Earthsized planet getting almost the same amount of light as Earth, around the closest star other than the Sun?

Impossible to tell without knowing how common are Earth sized planets that receive similar amount of light.

[Spaceception]

Pictures!!