ESO: Closest Temperate World Orbiting Quiet Star Discovered

[bystander]

Closest Temperate World Orbiting Quiet Star Discovered
ESO Science Release | HARPS | 2017 Nov 15

ESO’s HARPS instrument finds Earth-mass exoplanet around Ross 128

The sky around the red dwarf star Ross 128 Credit: Digitized Sky Survey 2. Acknowledgement: Davide De Martin

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A temperate Earth-sized planet has been discovered only 11 light-years from the Solar System by a team using ESO’s unique planet-hunting HARPS instrument. The new world has the designation Ross 128 b and is now the second-closest temperate planet to be detected after Proxima b. It is also the closest planet to be discovered orbiting an inactive red dwarf star, which may increase the likelihood that this planet could potentially sustain life. Ross 128 b will be a prime target for ESO’s Extremely Large Telescope, which will be able to search for biomarkers in the planet's atmosphere.

A team working with ESO’s High Accuracy Radial velocity Planet Searcher (HARPS) at the La Silla Observatory in Chile has found that the red dwarf star Ross 128 is orbited by a low-mass exoplanet every 9.9 days. This Earth-sized world is expected to be temperate, with a surface temperature that may also be close to that of the Earth. Ross 128 is the “quietest” nearby star to host such a temperate exoplanet. ...

Many red dwarf stars, including Proxima Centauri, are subject to flares that occasionally bathe their orbiting planets in deadly ultraviolet and X-ray radiation. However, it seems that Ross 128 is a much quieter star, and so its planets may be the closest known comfortable abode for possible life. ...

A Temperate Exo-Earth Around a Quiet M Dwarf at 3.4 Parsecs - X. Bonfils et al

• Astronomy & Astrophysics 613:A25 (May 2018) DOI: 10.1051/0004-6361/201731973
  arXiv.org > astro-ph > arXiv:1711.06177 > 16 Nov 2017

[Jim Leff]

https://www.nytimes.com/2017/11/15/scie ... s-128.html

Astronomers announced on Wednesday the discovery of an Earth-size planet around a small red star in our corner of the galaxy. The planet could hold liquid water and conditions favorable for life.

The star, Ross 128, is not the closest with a planet similar in size to ours. That would be the sun’s next door neighbor, Proxima Centauri, just 4.2 light-years away.

[Jim Leff]

Cool news! But I don't think you need to be very capricious or speculative to question statements like this:

it is close enough to Ross 128 that it absorbs warmth sufficient for liquid water, one of the requisite ingredients for life

After a couple Copernican revolutions, it's disappointing that we still seem to project human/earth-centric assumptions. We have no idea how matter gets animated with life. We really ought to maintain an open mind on this question, above all others, IMO....

[Chris Peterson]

Cool news! But I don't think you need to be very capricious or speculative to question statements like this:

it is close enough to Ross 128 that it absorbs warmth sufficient for liquid water, one of the requisite ingredients for life

After a couple Copernican revolutions, it's disappointing that we still seem to project human/earth-centric assumptions. We have no idea how matter gets animated with life. We really ought to maintain an open mind on this question, above all others, IMO....

The only kind of life we are familiar with, the only kind that we are reasonably able to detect, depends upon water. So the statement is very reasonable. It doesn't discount other forms of life, it simply doesn't consider them.

And FWIW, astrobiologists have looked seriously at alternate chemistries, and have had a hard time figuring out a way to produce life without carbon, hydrogen, and water. That doesn't mean it's impossible, of course, but it's a good argument that any life we find will be similar to ours in terms of fundamental chemistry.

[MargaritaMc]

See http://asterisk.apod.com/viewtopic.php?f=31&t=37760 for the ESO science release about this

[neufer]

Cool news! But I don't think you need to be very capricious or speculative to question statements like this:

it is close enough to Ross 128 that it absorbs warmth sufficient for liquid water, one of the requisite ingredients for life

After a couple Copernican revolutions, it's disappointing that we still seem to project human/earth-centric assumptions. We have no idea how matter gets animated with life. We really ought to maintain an open mind on this question, above all others, IMO....

The only kind of life we are familiar with, the only kind that we are reasonably able to detect, depends upon water. So the statement is very reasonable. It doesn't discount other forms of life, it simply doesn't consider them.

requisite (adj.) mid-15c., from Latin requisitus, past participle of requirere (see require).

require (v.) late 14c., "to ask a question, inquire," from Old French requerre "seek, procure; beg, ask, petition; demand," from Vulgar Latin *requaerere, from Latin requirere "seek to know, ask," from re-, here perhaps meaning "repeatedly" (see re-), + quaerere "ask, seek" (see query (v.)).

prerequisite (n.) 1630s "something required beforehand," 1650s (adj.),
"required beforehand," both from pre- + requisite.

require (v.) The original sense of this word has been taken over by request (v.). Sense of "demand (someone) to do (something)" is from 1751, via the notion of "to ask for imperatively, or as a right" (late 14c.).

[Jim Leff]

The only kind of life we are familiar with, the only kind that we are reasonably able to detect, depends upon water. So the statement is very reasonable.

The only view we'd ever had of the sky seemed to show celestial objects spinning around us. So it was a "very reasonable statement" to suppose our centrality. Then we realized we were incorrect in presuming specialness and centrality. Same when we discovered we're not central in the Milky Way. Woops. Shouldn't presume ourselves central/special. Same when we discovered that planetary nebula were galaxies....and we're not in an interesting or central one. Again: not central/special. We're not prototypical, and it's generally going to drive us to wrong conclusions if we assume otherwise.

And yet here we are.

I understand it's difficult to imagine non-carbon, non earth-like life. But it's in no way "VERY REASONABLE" to assume it will be carbon-based or otherwise similar to what we see on earth. There is absolutely no reason whatsoever for such an assumption.

And FWIW, astrobiologists have looked seriously at alternate chemistries, and have had a hard time figuring out a way to produce life without carbon, hydrogen, and water.

<sarcasm>Hey, astrobiolgists ought to know!</sarcasm>

I know they have. And it means nothing. Zero.

That doesn't mean it's impossible, of course, but it's a good argument that any life we find will be similar to ours in terms of fundamental chemistry.

No it's not a good argument. It's perhaps a minimally acceptable initial working assumption, strictly due to our lack of imagination in conjuring up other hypothetical models (i.e. it's all we've got), but it's no argument at all. And since you're a very bright fellow who surely took at least intro logic, I'm not going to spend further time arguing.

[Ann]

Interesting, Jim, and you may be right, of course.

But I think that until we can find some sort of scientific proof that non-carbon-based life not dependent on liquid water either actually exists, or certainly could exist, then non-carbon-based life not dependent on liquid water remains a matter of speculation. There are many things we can only speculate about, and we don't know how to find any real knowledge about them, let alone find positive proof that these things actually exist. The best examples might be what existed before the Big Bang, or whether there is a multiverse out there, and how we could possibly visit another universe.

The suggestion that there might be non-carbon-based life not dependent on liquid water out there doesn't seem inherently crazy to me, but until we see some signs of such life, either in the Universe itself, or in our computer models, then I think it is reasonable to talk about life as "life as we know it". By that, I certainly don't suggest that we should stop looking for other kinds of life.

I might add that I don't see life (at least multicellular, let alone intelligent life) as a "commandment" dictating the evolution of the Universe. I don't see why the Universe would be "obliged" to make multicellular, intelligent life on billions or even millions of planets in every galaxy in the Universe.

Chris has often argued that simple life forms might be extremely common in the Universe. I can't argue with you there, Chris, not because I'm convinced that you are right, but because I think that you may well be right.

But complex, intelligent life is another matter, and non-carbon-based life not dependent on liquid water is another matter still.

To paraphrase Einstein, I think that the Universe may indeed be playing dice. But I suspect that the dice of the Universe has billions of faces, and only one of those faces leads to intelligent, complex life. That face was the one that came up for the Earth when the Universe was playing dice for the fate of our solar system. And the Universe certainly used carbon-based compounds and liquid water to make us.

The rarity of intelligent life, and the tendency of life in the Universe to be carbon-based and dependent on liquid water, is what I believe in. But I have no more proof to back up my belief that I think you have to back up yours, Jim.

Ann

[geckzilla]

Why, there are a bunch of ethanol-based life forms right here on Earth...

[Chris Peterson]

The only kind of life we are familiar with, the only kind that we are reasonably able to detect, depends upon water. So the statement is very reasonable.

The only view we'd ever had of the sky seemed to show celestial objects spinning around us. So it was a "very reasonable statement" to suppose our centrality.

Only in a very different sense than what "reasonable" means today. We now have a much more accurate understanding of how the Universe works. We now have the ability to apply reason in ways that we did not 1000 years ago.

Shouldn't presume ourselves central/special.

You are very much misunderstanding my comments if you think this is what I'm suggesting.

I understand it's difficult to imagine non-carbon, non earth-like life.

Actually, it's not so terribly difficult. The reality is that our knowledge of chemistry and physics now makes it possible for us to do just that. To create feasible models of life-like processes that utilize other chemistries, to simulate the results, to make predictions.

But it's in no way "VERY REASONABLE" to assume it will be carbon-based or otherwise similar to what we see on earth. There is absolutely no reason whatsoever for such an assumption.

And precisely because we are able to actually address the possible chemistries of life in a scientific way, it becomes reasonable to assume that life is likely to be based on carbon and water chemistries. That is not at all the same as saying that there might not be other forms of life. It's just about what's reasonable.

And FWIW, astrobiologists have looked seriously at alternate chemistries, and have had a hard time figuring out a way to produce life without carbon, hydrogen, and water.

<sarcasm>Hey, astrobiolgists ought to know!</sarcasm>

Well, yes. They should. They are the experts we should be looking to. I don't understand why you discount their work so casually.

FWIW, the reasonableness of looking for life utilizing carbon-water chemistries goes beyond scientific theory, as well. We are looking at worlds which are very similar to Earth- terrestrial water worlds. And we know a lot about how our sort of life will produce detectable chemical signatures. So again, it is reasonable to look for what we know how to find.

[Chris Peterson]

Why, there are a bunch of ethanol-based life forms right here on Earth...

AKA carbon-water chemistry.

[bystander]

...
I understand it's difficult to imagine non-carbon, non earth-like life. But it's in no way "VERY REASONABLE" to assume it will be carbon-based or otherwise similar to what we see on earth. There is absolutely no reason whatsoever for such an assumption. ...

Three of the four most abundant elements in the universe are hydrogen, oxygen, and carbon. Why is not "VERY REASONABLE" to assume life is based upon those elements? (The fourth is helium which is not reactive.)

Another essential element to life as we know it, nitrogen, is also among the top seven, joined by iron and neon (another non-reactive element). The other elements each contribute less than 0.1%.

[rstevenson]

And it's not just the abundance of those few elements that make life based on them very reasonable. It's also the amount of energy required in their various reactions. It's hard to imagine life opting for reactions that require more energy input, no matter what sort of strange environment they might be occurring in. It seems likely that evolution will always favour the shortest, most energy-efficient path.

Rob

[geckzilla]

Why, there are a bunch of ethanol-based life forms right here on Earth...

AKA carbon-water chemistry.

The connoisseurs seem convinced enough that alcohol is its own element, anyway.

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Jim's argument is that searching for Earth-like life is essentially geocentrism, and geocentrism is always wrong, ergo assuming other life must be Earth-like must be wrong.

I think you all are on the right track by showing that it is not the same as the geocentric model. Furthermore, it is not an anthropocentric model. There's the fallacy—to think that humans are unique. Indeed, we are made of the same materials as all other known life. It is most amusing to me that an anti-anthropocentric argument seems to contain an anthropocentric fallacy.

[Chris Peterson]

And it's not just the abundance of those few elements that make life based on them very reasonable. It's also the amount of energy required in their various reactions. It's hard to imagine life opting for reactions that require more energy input, no matter what sort of strange environment they might be occurring in. It seems likely that evolution will always favour the shortest, most energy-efficient path.

That's a very strong argument- scientifically supported- for complex life. Carbon-hydrogen chemistry with water as a solvent is almost certainly the most energy efficient. If life exists with fundamentally different chemistries, it's much more likely that it will be very simple- analogous to prokaryotic cells.

[Jim Leff]

Busy for next couple days, but I'll reply to this one posting now and to the others later in the week. Thanks for your thoughts.

Three of the four most abundant elements in the universe are hydrogen, oxygen, and carbon. Why is not "VERY REASONABLE" to assume life is based upon those elements? (The fourth is helium which is not reactive.)

Bystander, I enjoy and value your postings (Chris', too!), so please don't feel disrespected, but I've parsed your question 8 or 9 times and I can't see, from any conceivable angle, that you're actually saying anything.

You're stating a fact, and it's true, but I don't see the slightest relevance or connection. I almost suspect this is some sort of Zen koan, concocted to stop my mind and flip me into nirvana. "My bicycle is blue; why shouldn't pizza be spicy?"

[bystander]

Jim, if you can't see the reasonableness of assuming that life would be based on what is most likely available and most energy efficient, I'm quite sure that you would fail to see any relevance or connection in any thing else that I could add.

[Jim Leff]

<sarcasm>Hey, astrobiolgists ought to know!</sarcasm>

Well, yes. They should. They are the experts we should be looking to. I don't understand why you discount their work so casually.

The idea that astrobiologists should be assumed to have special knowledge of the biology of extraterrestrial life is...well, adorable to me. We're just the cutest organisms, aren't we?

How about "futurists"? Do you defer to their expertise re: the future?

I'm sure those guys do intelligent work of some sort that serves a very useful purpose. But unless I've missed an important news report, they have no knowledge of extraterrestrial biology. They know incomparably less about extraterrestrial biology than we know about about fashion styles in year 4000.

[Jim Leff]

And it's not just the abundance of those few elements that make life based on them very reasonable. It's also the amount of energy required in their various reactions. It's hard to imagine life opting for reactions that require more energy input, no matter what sort of strange environment they might be occurring in. It seems likely that evolution will always favour the shortest, most energy-efficient path.

Rob

But back up.

We don't know how aliveness happens. Once kindled, we certainly know a lot about what helps life thrive, and what makes it decline and extinguish. But animation itself is still a complete mystery. If I give you a pile of chemical materials and energy sources, you will not be able to animate it. Even if I give you a nearly optimized arrangement of those materials (i.e. a corpse), you still will only flounder. We know a lot about the machine, but nothing about the ghost.

Having no idea how matter animates, we certainly can't anticipate how it will animate on alien worlds. The supposition that it would thrive or decline from the factors that make it thrive or decline on Earth seems extraordinarily primitive, ala pre-Copernican thinking re: the cosmos.

[geckzilla]

But back up.

We don't know how aliveness happens. Once kindled, we certainly know a lot about what helps life thrive, and what makes it decline and extinguish. But animation itself is still a complete mystery. If I give you a pile of chemical materials and energy sources, you will not be able to animate it. Even if I give you a nearly optimized arrangement of those materials (i.e. a corpse), you still will only flounder. We know a lot about the machine, but nothing about the ghost.

Having no idea how matter animates, we certainly can't anticipate how it will animate on alien worlds. The supposition that it would thrive or decline from the factors that make it thrive or decline on Earth seems extraordinarily primitive, ala pre-Copernican thinking re: the cosmos.

Chemistry. I've got a certain group of friends who practice this application of chemistry who are pretty good at keeping a human body from dying or bringing it back from the verge of death with the right chemicals. And a corpse cannot be reanimated because once the chemical machinery fails, we have no way to go back in and repair it. A brain contains a specific pattern, and cellular death destroys that pattern. Just because it's impossible to rearrange it back to the way it was doesn't mean we have no clue how it happens or why it's impossible.

[Jim Leff]

You're talking past my point. I'm aware of science and medicine.

The problem with a corpse isn't that it's broken. It's that we don't know how matter animates. We have no idea.

[Chris Peterson]

<sarcasm>Hey, astrobiolgists ought to know!</sarcasm>

Well, yes. They should. They are the experts we should be looking to. I don't understand why you discount their work so casually.

The idea that astrobiologists should be assumed to have special knowledge of the biology of extraterrestrial life is...well, adorable to me.

Why shouldn't they? Chemistry and physics are the same everywhere. The form of life is guided by evolution, which is not predictable. But the chemistry of life is a subject open to solid scientific analysis. The kinds of chemical reactions that can result in replication. In energy transfer. In interactions with the environment.

How about "futurists"? Do you defer to their expertise re: the future?

Do you know any futurists who apply the scientific method to their predictions?

I'm sure those guys do intelligent work of some sort that serves a very useful purpose. But unless I've missed an important news report, they have no knowledge of extraterrestrial biology. They know incomparably less about extraterrestrial biology than we know about about fashion styles in year 4000.

Perhaps you should read some of the research they're producing before passing such harsh judgment.

[Chris Peterson]

And it's not just the abundance of those few elements that make life based on them very reasonable. It's also the amount of energy required in their various reactions. It's hard to imagine life opting for reactions that require more energy input, no matter what sort of strange environment they might be occurring in. It seems likely that evolution will always favour the shortest, most energy-efficient path.

But back up.

We don't know how aliveness happens. Once kindled, we certainly know a lot about what helps life thrive, and what makes it decline and extinguish.

But we do know a lot about that. We know that it isn't "kindled", but occurs along a continuum. It isn't a big mystery.

If I give you a pile of chemical materials and energy sources, you will not be able to animate it.

Are you sure? This has been done in the lab. Life created following models of existing life. And we're very close to doing it for novel life.

Even if I give you a nearly optimized arrangement of those materials (i.e. a corpse), you still will only flounder. We know a lot about the machine, but nothing about the ghost.

There is no ghost. It's just chemistry, and it's chemistry we understand pretty well.

[geckzilla]

You're talking past my point. I'm aware of science and medicine.

The problem with a corpse isn't that it's broken. It's that we don't know how matter animates. We have no idea.

You have no idea.

[neufer]

Click to play embedded YouTube video.