ESO: Closest Temperate World Orbiting Quiet Star Discovered

[BDanielMayfield]

...
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%.

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.

If life exists elsewhere, which is likely, it is only reasonable to expect it to require both water and cabon. This is because both are abundant, because water is such a good solvent, and because carbon chain molecules can have unlimited combinations of configurations, shapes, etc. No other element can match carbon in its versatility.

I agree with Jim Leff's comments here:

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.

, but I wouldn't use the word "ghost".

It spite of Chris' assurances that life must arise fairly easily given the right set of conditions, this remains an unproven assumption. Even so called simple life is extremely complex.

Bruce

[geckzilla]

Sometimes I think the problem with humanity is that we are at the top of the list of intelligent animals, so we make the mistake of thinking we're highly intelligent. Sure, we are of relatively high intelligence, but I'm pretty sure we're not all that smart in an absolute sense. DNA seems utterly incomprehensible, because our brains can't readily comprehend it. We stumble over things like consciousness because our brain is totally unaware of itself. Just how conscious are we?

[neufer]

Click to play embedded YouTube video.

Sometimes I think the problem with humanity is that we are at the top of the list of intelligent animals, so we make the mistake of thinking we're highly intelligent. Sure, we are of relatively high intelligence, but I'm pretty sure we're not all that smart in an absolute sense. DNA seems utterly incomprehensible, because our brains can't readily comprehend it. We stumble over things like consciousness because our brain is totally unaware of itself. Just how conscious are we?

• But we use words... the BEST words

[BDanielMayfield]

Sometimes I think the problem with humanity is that we are at the top of the list of intelligent animals, so we make the mistake of thinking we're highly intelligent. Sure, we are of relatively high intelligence, but I'm pretty sure we're not all that smart in an absolute sense. DNA seems utterly incomprehensible, because our brains can't readily comprehend it. We stumble over things like consciousness because our brain is totally unaware of itself. Just how conscious are we?

It is good to be humble, both personally and as a species, but otoh isn't the human brain the most complex structure found in nature? We have great potential for intelligence, but the problem is that relatively few of us use our brains wisely.

"Question everything."

[geckzilla]

It is good to be humble, both personally and as a species, but otoh isn't the human brain the most complex structure found in nature?

By what measurement? By our seeming lack of understanding it? Because then a black hole, dark matter, dark energy, the big bang, or any number of astrophysical objects or concepts might win. By the difficulty of creating something like it? Because we're getting pretty darn close with computers. One imagines it won't be much longer. By size? It's hardly that big. As a species, we don't even have the biggest brains on our own planet. Is this just one of those things that sounds about right, so people repeat it—ironically—without thinking? When you get down to it, the human brain is just a pattern computer. Consciousness is just success at recognizing one's own pattern. Congrats on that, humanity.

[Doum]

i think from what we know or what i think i know about life:

500 to 800 millions years after earth creation, life appear. Primitive life. It stay a very primitive lifeform for around 3.5 billions years (almost all of the earth age). Then 500 millions years ago it evolve untill today. Wich was fast compare to the age of earth.

So when earth was still bombard by meteor life seem to appear in this harsh environment. Just from that i suppose that life dont have a problem to appear. As if it is common for it to happen. It didnt seem to be luck for it to happen that early after earth was born.

Evolve life seem to be more difficult to happen. Way more difficult. As if its a luck when it happened. It seem to need a lot of right condition. So, may be finding alien intelligence will be hard to do. Or just finding animal on other planets might be rare (if we can go there someday).

Since we only have earth as an exemple for life appearing and evolving late in his history, i can only assume on what i know. As for other kind of lifeform, well we can speculate only. We have no bases to know. (May be exobiologist will find out someday)

All of the above is just a thought. But to my opinion, life seem easy to appear but very hard to evolve. Are we lucky to exist.

May be. May be not.

So : To be or not to be

[Chris Peterson]

So when earth was still bombard by meteor life seem to appear in this harsh environment. Just from that i suppose that life dont have a problem to appear. As if it is common for it to happen. It didnt seem to be luck for it to happen that early after earth was born.

Yeah, that's how I see it, too. It happened so fast and under such harsh conditions that it seems like it might be an inevitable thing. In a rich environment, it's only a matter of time until some sort of chemical appears which can minimally replicate itself, and once that happens, you have evolution. And once you have evolution, I don't see how life can fail to follow, along with increasing complexity.

Evolve life seem to be more difficult to happen. Way more difficult. As if its a luck when it happened. It seem to need a lot of right condition. So, may be finding alien intelligence will be hard to do. Or just finding animal on other planets might be rare (if we can go there someday).

I'm assuming that by "evolve" you actually mean "complex". If so, then yes, I agree. It took a lot long for significant complexity to occur, and the amount of time that significantly intelligent life has been present is so short that we might treat it as nothing but an aberration.

[Doum]

An aberration is a good word to describe it. I like it.

As for evolve and complex life form. yes, it is what i mean.

My writing in english aint that good. So finding the right word is not easy. That is why i am often wrong ( It is a normality for me).
You should ear my speaking.

[BDanielMayfield]

So when earth was still bombard by meteor life seem to appear in this harsh environment. Just from that i suppose that life dont have a problem to appear. As if it is common for it to happen. It didnt seem to be luck for it to happen that early after earth was born.

Yeah, that's how I see it, too. It happened so fast and under such harsh conditions that it seems like it might be an inevitable thing. In a rich environment, it's only a matter of time until some sort of chemical appears which can minimally replicate itself, and once that happens, you have evolution. And once you have evolution, I don't see how life can fail to follow, along with increasing complexity.

Evolve life seem to be more difficult to happen. Way more difficult. As if its a luck when it happened. It seem to need a lot of right condition. So, may be finding alien intelligence will be hard to do. Or just finding animal on other planets might be rare (if we can go there someday).

I'm assuming that by "evolve" you actually mean "complex". If so, then yes, I agree. It took a lot long for significant complexity to occur, and the amount of time that significantly intelligent life has been present is so short that we might treat it as nothing but an aberration.

I agree that the fossil record shows that life has a long history on this very old planet, and that the first life had to be able to survive harsh conditions. This shows that early life here had to be tough, right from the start. The harshness of the environment would require robust organisms, right from the start. This suggests to me that the seeding of life engineered to be able to withstand such conditions is at the very least a plausible alternative explanation.

Bruce

[Chris Peterson]

I agree that the fossil record shows that life has a long history on this very old planet, and that the first life had to be able to survive harsh conditions. This shows that early life here had to be tough, right from the start. The harshness of the environment would require robust organisms, right from the start. This suggests to me that the seeding of life engineered to be able to withstand such conditions is at the very least a plausible alternative explanation.

Plausible. But not likely I think, and not necessary. I assume that the primitive roots of life were not robust at all. Fragile molecules that formed and failed. But with replication, there was no way to go but towards more robustness. Natural selection is an inexorable force.

[BDanielMayfield]

I agree that the fossil record shows that life has a long history on this very old planet, and that the first life had to be able to survive harsh conditions. This shows that early life here had to be tough, right from the start. The harshness of the environment would require robust organisms, right from the start. This suggests to me that the seeding of life engineered to be able to withstand such conditions is at the very least a plausible alternative explanation.

Plausible.

Hey, I'll take that. It at least acknowledges a possibility.

But not likely I think, and not necessary. I assume that the primitive roots of life were not robust at all. Fragile molecules that formed and failed. But with replication, there was no way to go but towards more robustness. Natural selection is an inexorable force.

So goes the general, consensus viewpoint. I still think the harshness of the early Earth argues in favor of life getting a boost over the gap between inanimate and living matter.

Life is a powerful force. Life force. That's the expression I'd substitute for "ghost" in Jim Leff's comment.

Bruce

[Chris Peterson]

Life is a powerful force. Life force.

I don't even know what that means. Life is chemistry. Like baking soda and vinegar. The Universe is full of complex systems created and sustained by external energy sources. Life is just one of many. Not a "force" in any sense of the word. Just physics.

[neufer]

Click to play embedded YouTube video.

Life is a powerful force. Life force.

I don't even know what that means. Life is chemistry. Like baking soda and vinegar. The Universe is full of complex systems created and sustained by external energy sources. Life is just one of many. Not a "force" in any sense of the word. Just physics.

[Doum]

Life appear in what we consider harsh environment. But fot that lifeform it aint that harsh. So it replicate relatively easy. But also for it to evolve it need a change in the environment. And it doesnt seem to have happened frequently (over a few billion of years).

So, if condition are there, life will appear.

Mehhh, that sound like creationist.

[BDanielMayfield]

Young Earth Creationists with their stubborn refusal to accept scientific facts about the ages of both the Earth and the Universe and the role of natural selection in the diversity of life have besmirched the words creationist, creationism, etc. They hurt their cause enormously because of this, along with all the other ______ (insert expletive) and evil done by and in the support of religion.

Bruce, most definitely not a YECer

[BDanielMayfield]

Life appear in what we consider harsh environment. But fot that lifeform it aint that harsh. So it replicate relatively easy. But also for it to evolve it need a change in the environment. And it doesnt seem to have happened frequently (over a few billion of years).

So, if condition are there, life will appear.

I understand your point. The first life would be what we call extremophiles, happily replicating themselves in boiling pools of anoxic acid. Maybe that's a bit too extreme, but my point is that the early environment would have been corrosive. How could an exposed molecule of RNA survive that before it has given the instructions to erect a protective cell wall?

Bruce

[Chris Peterson]

I understand your point. The first life would be what we call extremophiles, happily replicating themselves in boiling pools of anoxic acid. Maybe that's a bit too extreme, but my point is that the early environment would have been corrosive. How could an exposed molecule of RNA survive that before it has given the instructions to erect a protective cell wall?

Why assume it would be RNA? That's a much more complex molecule than required for replication. And why assume such a harsh environment? Even in early oceans, it need not be so hot or so reducing/oxidizing as to destroy or denature simple polymers. Indeed, why assume these primitive self-replicating molecules were even free in solution, as opposed to bound to minerals? And being anoxic is a plus, since oxygen is generally toxic to most biological processes. It took a long time for life to figure out how to safely utilize it for its energetic value without it poisonous qualities being a problem (and indeed, those properties remain a problem for complex life).

Assuming free proto-life molecules, there was no early need to build their own cell walls, because nature readily provides lipid vesicles on its own, which would be capable of trapping organic molecules (something which has been experimentally demonstrated).

[Doum]

One of the reason life stagnate for a long period on earth.

http://www.spacedaily.com/reports/Limit ... e_999.html

And an informative article how life is strong.

http://www.spacedaily.com/reports/Scien ... s_999.html

[Doum]

that one is interesting.

When water met iron deep inside the Earth, did it create conditions for life?

https://phys.org/news/2017-11-met-iron- ... tions.html

[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.

You have no idea.

You do? Cool! Be sure and shoot a video!

[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.

You do? Cool! Be sure and shoot a video!

It's not something that a single video can illustrate. I would suggest that you simply buy an introductory biology book that includes all the chemistry that goes on in plant and animal cells.

[Chris Peterson]

You have no idea.

You do? Cool! Be sure and shoot a video!

It's not something that a single video can illustrate. I would suggest that you simply buy an introductory biology book that includes all the chemistry that goes on in plant and animal cells.

I suspect a logical fallacy on Jim's part to conclude that the opposite of "no idea" is "completely understand".

[geckzilla]

Heh, maybe so. I certainly don't completely understand it. It is not an uncommon topic with the hubby, though. Understanding disease processes also requires an good understanding of the basic nature of cells and how they interact with one another. The immune system is also absolutely fascinating.

[bystander]

Rocky Planet Neighbor Looks Familiar, but Is Not Earth's Twin
Carnegie Institution for Science | 2018 Jul 10

This artist’s impression shows the temperate planet Ross 128 b, with its red dwarf parent star in the background. (Credit: ESO/M. Kornmesser)

---

Last autumn, the world was excited by the discovery of an exoplanet called Ross 128 b, which is just 11 light years away from Earth. New work from a team led by Diogo Souto of Brazil’s Observatório Nacional and including Carnegie’s Johanna Teske has for the first time determined detailed chemical abundances of the planet’s host star, Ross 128.

Understanding which elements are present in a star in what abundances can help researchers estimate the makeup of the exoplanets that orbit them, which can help predict how similar the planets are to the Earth. ...

The team determined that Ross 128 has iron levels similar to our Sun. Although they were not able to measure its abundance of silicon, the ratio of iron to magnesium in the star indicates that the core of its planet, Ross 128 b, should be larger than Earth’s.

Because they knew Ross 128 b’s minimum mass, and stellar abundances, the team was also able to estimate a range for the planet’s radius, which is not possible to measure directly due to the way the planet’s orbit is oriented around the star. ...

The estimated radius of Ross 128 b indicates that it should be rocky.

Lastly, by measuring the temperature of Ross 128 and estimating the radius of the planet the team was able to determine how much of the host star’s light should be reflecting off the surface of Ross 128 b, revealing that our second-closest rocky neighbor likely has a temperate climate. ...

Stellar and Planetary Characterization of the Ross 128 Exoplanetary System from APOGEE Spectra - Diogo Souto et al

• Astrophysical Journal Letters 860(1):L15 (2018 Jun 10) DOI: 10.3847/2041-8213/aac896
  arXiv.org > astro-ph > arXiv:1805.11633 > 29 May 2018 (v1), 14 Jun 2018 (v2)