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


Spaceception

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That's a shame.

However, the knowledge of such a planet may change the JWST mission plan in some ways or result in a specially designed telescope. This may be the first planet other than Earth and Mars that humans will land on :D

Plans in this directions, 
http://www.nextbigfuture.com/2016/08/upcoming-telescopes-that-will-provide.html

Edited by magnemoe
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8 hours ago, Green Baron said:

@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 ...

 

Well, on the other hand red dwarves last quite a bit longer, potentially giving evolution plenty of time, even if it's slow... Assuming offcourse habitability of planet lasts long enough. Not betting on life on this particular one tho...

However... A small habitable zone, that could last for eg. 50-100 mio. years more (A far cry from over all red dwarf lifespans)... would be a decent beginners backup site. If we can get there... A big if...

 

Edited by 78stonewobble
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1 hour ago, 78stonewobble said:

Well, on the other hand red dwarves last quite a bit longer, potentially giving evolution plenty of time, even if it's slow... Assuming offcourse habitability of planet lasts long enough. Not betting on life on this particular one tho...

However... A small habitable zone, that could last for eg. 50-100 mio. years more (A far cry from over all red dwarf lifespans)... would be a decent beginners backup site. If we can get there... A big if...

 

Uh, try 'billions', at least theoretically.

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Since Nature already paywalled the paper, have a preprint hosted by ESO.

 

Annoyingly, there is a lack of transit detection that manages to mean rather little because they only got to 5% depth. (ie: excludes something neptune sized being edge-on, but for a rocky body in this mass range? ¯\_(ツ)_/¯) I'm not touching actual habitability with a 10 km baseline interferometer given the current unknowns.

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How Proxima b could be habitable, and the challenges it faces.

https://palereddot.org/opportunities-and-obstacles-for-life-on-proxima-b/

There also seems to be an unconfirmed planet with an orbit of a little less than 200 days, which is mentioned in the article.

Edited by Spaceception
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2 hours ago, Spaceception said:

Looks like the planets around Ross and Barnard's don't want to be found.

 

I find Ross 154 to be a rather odd choice for a long-term search for potentially habitable planets. While it's small size would make detection of habitable zone planets easier, the tiny star has quite the attitude. It's classified as a UV Ceti flare star, and it can put Proxima and Trappist-1 to SHAME. Huge flares erupt on its surface about once every two days - not as quick as Trappist-1, but these are much more powerful. On average, a flare from Ross 154 would increase its brightness by 3-4 magnitudes. That is a HUGE increase in luminosity. While Trappist-1 may have flares that rival the most powerful every put out by our Sun (as far as we know), Ross 154 makes such flares look like sparklers. In addition, the star is less than a billion years old, which makes the prospect of biosignature-producing life pretty low, excluding the flares I just mentioned. But there might be a ray of hope. Large icy planets with underground oceans like Europa would not have their habitability compromised by flare events. Also, based on worlds like LHS 1140b and K2-3d, it seems like the habitable zone area around red dwarfs is where much of the system's iron is, which would form a dense planet with a powerful magnetosphere. One final note is that there's a chance of life developing (and staying) in underground water reserves on desert planets. Now, with all that in mind, where would promising worlds be located around Ross 154? The star has about 0.0038 times the luminosity of the Sun, which means that it's conservative habitable zone ranges from 0.058775 to 0.8467474 AU, with orbital periods between 12.614-21.8122 days and equilibrium temperatures ranging from 261*K to 217*K. Now for the optimistic habitable zone, which I will constrain with a temperature range from 305*K to 180*K. With these values, the inner limit is marked by a 7.8935-day orbit at 0.0430 AU, and the outer limit is marked by a 38.2345-day orbit at 0.1231 AU. A safe area for iron planets would be from 15 to 40 days (246-178*K), as they would likely have significant greenhouse effects. Some smaller iron worlds could reside closer to the 12-day boundary. Europa-like planets would probably have equilibrium temperatures less than 230*K, and thus would have orbital periods greater than 18 days. Finally, Earth-sized desert worlds can be potentially habitable with orbital periods between 7.5 and 30.5 days. Planets with more than 2 Earth masses would be safer with years greater than 8-10 days.

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@ProtoJeb21 Maybe they're trying to find the limits of what HZ planets can handle? Flares are bad, but we haven't studied planets orbiting those in detail, and there are variables that can allow planets to survive, plus they would find interesting targets we can study in the short term, unlike Kepler.

Edited by Spaceception
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11 hours ago, Spaceception said:

@ProtoJeb21 Maybe they're trying to find the limits of what HZ planets can handle? Flares are bad, but we haven't studied planets orbiting those in detail, and there are variables that can allow planets to survive, plus they would find interesting targets we can study in the short term, unlike Kepler.

That's an interesting take on it. Like I was saying in my previous post, iron planets might have magnetic fields durable enough for this environment, and Europa-like planets won't be affected by a high flare rate.

Now for Barnard's star, which is both better and worse than Ross 154. It's a very small, old, and calm star. I didn't find anything about any major flares, which is expected due to its long rotation period of 130 days. However, despite a life-friendly environment, Barnard is EXTREMELY metal poor. It has only about 10-35% the heavy element content as our Sun, which makes finding planets less likely. If there are any, they would either be Mars-sized rocky worlds, or Earth-sized ocean planets or gas dwarfs. The latter two would provide quite a unique opportunity to do thorough investigation of a rare planet class. I mean, the only planet that would count as an Earth-sized water/gas world would be Kepler-138d, with 1.21 RE and 0.64 ME. While the Kepler-138 system is one of the best studied Kepler systems, it is rather distant at 217 light-years away. By comparison, Barnard is just 6 light-years! So if PRDs manages to find a transiting gas dwarf or waterworld around Barnard, it would be an incredibly opportunity to study such a bizarre and rare planet class.

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43 minutes ago, Spaceception said:

Do you guys think we'll find planets around Barnard's star.

Based on what Mendez said on the official Barnard's Star search press release, it seems like there is a possible super-Earth mass planet in that system. I believe it may be a gas dwarf due to the low metal content of Barnard and how it was said that this candidate was in the cold region of the system. 

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