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BREAKING: New potentially habitable exoplanet found around Teegarden's star

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#51 russell23

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Posted 22 June 2019 - 12:38 PM

If we are quoting scripture:

 

https://www.youtube....h?v=b240PGCMwV0

Great lecture segment!

 

Nothing in there contradicts the clarifications I made.



#52 russell23

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Posted 22 June 2019 - 12:48 PM

Titan.  And there are probably oceans under other Saturnian and Jovian moons - we just haven't sent the right instruments there yet.  Also Triton, Pluto...  

 

These are lot more interesting for astrobiology than exoplanets.  We could acuatally get samples back.  For exoplanets, the most we will get, even far in the future, is the sort of image we had of Pluto before New Horizons.  A few pixels, endlessly parsed, but never hinting at what we found there when we sent a probe.

This is an important area for exploration in the Solar System. 

 

Models for the differentiated interiors of the icy spherical Satellite Planets in the outer Solar System predict an internal ocean at some depth inside these planetary bodies.   The depth and thickness of the ocean will vary with the mass and composition of the body.   Some of these Satellite Planets are mostly rock with planetary ices composing the outer layers.  Others are mostly ice by mass with a smaller rocky core. 

 

What makes Europa particularly interesting is that the internal structure model has the sub-surface ocean sitting directly on a rocky mantle.  This means that there should be raw materials for life leaching into that ocean from the mantle rocks.  Other Satellite Planets have the subsurface ocean sandwiched between different ice layers so there will be less dissolved raw materials in those oceans. 

 

Like Europa, Pluto is mostly rock by mass. 



#53 TOMDEY

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Posted 22 June 2019 - 02:15 PM

I would say that for practical purposes, we are alone.  

But at least the problem has been solved for the case of the spherical cow.

Jon

Hi, Jon; I actually worked out the packing-density for spherical cows decades ago... but it assumes an infinitely-larger container. A bound container reduces the density, of course. Udder nonsense!

 

And you make an excellent point. Our projections are only as good as our model and available data... In this case... both are pathetically-lacking!  And the container is beginning to look like it is spherical, with a diameter only slightly larger than the diameter of a cow.

 

For those interested in the cute problem, try to figure out (from scratch... no internet, books or computer) the max-possible packing density for (equal-sized) spheres in Euclidian 3-space. Level of difficulty is not entirely trivial, but still quite ~Meh~. Bonus credit... same question for 1, 2, ... N-dimensional spaces. And the ultimate toughie - same problem for oblate spheroidal regular m&mand prolate spheroidal peanut m&ms!    Tom, uniquely Tom

Attached Thumbnails

  • 101 m and m packing spherical cow.jpg
  • 102 m and m packing spherical cow.jpg

Edited by TOMDEY, 22 June 2019 - 02:18 PM.


#54 Cpk133

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Posted 22 June 2019 - 02:31 PM

Have they detected any evidence of canals?



#55 areyoukiddingme

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Posted 22 June 2019 - 03:12 PM

Great lecture segment!

 

Nothing in there contradicts the clarifications I made.

 

Yes, I was very happy when I came across it. I have the unenviable task of explaining science to social science students, and this does the job beautifully.

 

It's also interesting in that he frames science as the search for laws. In my neck of the woods, we are just happy for p < .05.


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#56 gnowellsct

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Posted 22 June 2019 - 03:18 PM

The most wishful thinking in 1919 would never have imagined we would have millions of people comfortably flying almost anywhere in the world they desire.

 

Cheers,

More like 1909 IMO.  In 1919 there would have been a basis for extrapolation.  Industrial scale production of aircraft, for one.



#57 gnowellsct

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Posted 22 June 2019 - 03:31 PM

Kevin:

 

I checked your calculations using both MathCad which understands units and my phone's calculator which does unit conversions and has the light-year as a unit. Both gave me 2.34 x 10-5 arc-seconds, this agrees with your number.  I also verified your 6000 meter aperture/separation.. 

 

That would be one large Dob.

 

Jon

An interferometric array might do the trick.  It would get the resolution.  Maybe you don't need all the light gathering.

 

https://www.aavso.or...ng-λ-andromedae

 

https://en.wikipedia...iki/CHARA_array

 

If we think of CHARA as a primitive forerunner we might do better on the imaging then one might guess at this juncture, in a decade or two or five.  

 

After all, a c8 today turns out better images of Saturn and Jupiter then you could have gotten from the Hale telescope back in the 1960s.  It isn't always about brute force aperture.

 

Greg N



#58 Edd Weninger

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Posted 23 June 2019 - 01:24 AM

No, by 1919 we had learned to make aircraft a weapon of war.  It took another decade to begin to think about using aircraft to move ordinary people about.

 

Cheers,



#59 InkDark

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Posted 23 June 2019 - 09:40 AM

Titan.  And there are probably oceans under other Saturnian and Jovian moons - we just haven't sent the right instruments there yet.  Also Triton, Pluto...  

 

These are lot more interesting for astrobiology than exoplanets.  We could acuatally get samples back.  For exoplanets, the most we will get, even far in the future, is the sort of image we had of Pluto before New Horizons.  A few pixels, endlessly parsed, but never hinting at what we found there when we sent a probe.

Yes Titan. I guess methane is a worthy solvant. But is it as good as water for life? 



#60 InkDark

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Posted 23 June 2019 - 09:47 AM

We don't know how rare cells are, but it's pretty amazing how easily the building blocks of life come together. The Urey-Miller experiments are an interesting read. I was told by a biology professor that they set up a number of long term experiments just tossing the ingredients in a pot, and freezing them for years, without even the electricity used in the first experiment. The ones at more moderate subfreezing temps did you'reresults, and he said they have another in a freezer at Harvard around -100 that's been running for decades.

Biuding blocks for life are pretty far from complex life as I understand it. Even thought I don't understand exaclty what are the limiting steps for a simple cell to produce or acquire a nucleus and an energy machinery as sophisticated and prodcutive as the mitochondria, it seems that life was caught in a rut for a very long time on Earth before something sparked the complex cell. 



#61 Phil Cowell

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Posted 23 June 2019 - 11:45 AM

No, by 1919 we had learned to make aircraft a weapon of war.  It took another decade to begin to think about using aircraft to move ordinary people about.

 

Cheers,

They were weapons of war for most of WWI. By 1919 many problems had been solved.


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#62 Araguaia

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Posted 23 June 2019 - 01:56 PM

Yes Titan. I guess methane is a worthy solvant. But is it as good as water for life? 

 

The methane lakes are on the surface of Titan, which is made of water ice (mostly).  There appears to be liquid water deep under the surface as well, touching rock.  There may also be contact between the methane lakes and the subsurface water ocean.  Quite a potent brew for life, that would be.



#63 denny-o

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Posted 24 June 2019 - 03:55 PM

I spent more than half my life immersed in the complexities of a multi celled organism. One thing I have always maintained is that the life force is not just complex aggregations of proteins and carbohydrates, the life force goes all the way down to the atomic level. Now this notion has a historical name, called the Vital Force. In the early 1800's a german chemist, name of  Wohler, produced the organic compound Urea artificially by treating silver cyanate with ammonium chloride. This supposedly was the wooden stake through the heart of the Vital Force. Maybe, maybe not. Urea is by definition an organic compound but it has no life of its own.

Now in 2010 the Venter group synthesized a complete DNA gene sequence from a computer record  (nucleotide printer - think 3D printer) and inserted it into a bacterial cell with it's DNA freshly removed. The Frankenstein bacteria went happily on, dividing and multiplying and creating a new family of bacteria that had no living ancestor.

Before we get all happy and high fiving (or predicting the end of Man) note that the DNA helix (a simple structure of 6 nucleotides) had to be inserted into a previously living cell with an active life force. The cell wall and all the internal components of a single cell organism are mind bendingly complex.

Maybe we will create life from scratch, maybe not.

I hope we will not - but then I am old, cranky, and probably should have shuffled off my life force long ago.



#64 Phil Cowell

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Posted 24 June 2019 - 08:35 PM

I spent more than half my life immersed in the complexities of a multi celled organism. One thing I have always maintained is that the life force is not just complex aggregations of proteins and carbohydrates, the life force goes all the way down to the atomic level. Now this notion has a historical name, called the Vital Force. In the early 1800's a german chemist, name of  Wohler, produced the organic compound Urea artificially by treating silver cyanate with ammonium chloride. This supposedly was the wooden stake through the heart of the Vital Force. Maybe, maybe not. Urea is by definition an organic compound but it has no life of its own.

Now in 2010 the Venter group synthesized a complete DNA gene sequence from a computer record  (nucleotide printer - think 3D printer) and inserted it into a bacterial cell with it's DNA freshly removed. The Frankenstein bacteria went happily on, dividing and multiplying and creating a new family of bacteria that had no living ancestor.

Before we get all happy and high fiving (or predicting the end of Man) note that the DNA helix (a simple structure of 6 nucleotides) had to be inserted into a previously living cell with an active life force. The cell wall and all the internal components of a single cell organism are mind bendingly complex.

Maybe we will create life from scratch, maybe not.

I hope we will not - but then I am old, cranky, and probably should have shuffled off my life force long ago.

The CRSPR CAS-9 allows for genetic modification using a virus as the delivery agent.

I’m looking forward to the day life is created from scratch. My guess it’ll be a very simple life form and within 20 years.

Probably in a similar timeframe the first legal case for intelligence in a non-organic device.



#65 EJN

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Posted 24 June 2019 - 08:48 PM

Or the corollary:

 

"If I have not seen further than others, it is because giants were standing on my shoulders."

 

Jon

 

I have seen further than others because I am surrounded by midgets. :yay:



#66 rowdy388

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Posted 24 June 2019 - 08:59 PM

I have seen further than others because I am surrounded by midgets. yay.gif

...and I have seen further because I have telescopes and they don't.  hamsterdance.gif 



#67 InkDark

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Posted 25 June 2019 - 09:05 AM

The methane lakes are on the surface of Titan, which is made of water ice (mostly).  There appears to be liquid water deep under the surface as well, touching rock.  There may also be contact between the methane lakes and the subsurface water ocean.  Quite a potent brew for life, that would be.

I did not know about water on Titan. Thanks for the info.


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#68 Araguaia

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Posted 25 June 2019 - 11:36 AM

 

Now in 2010 the Venter group synthesized a complete DNA gene sequence from a computer record  (nucleotide printer - think 3D printer) and inserted it into a bacterial cell with it's DNA freshly removed. The Frankenstein bacteria went happily on, dividing and multiplying and creating a new family of bacteria that had no living ancestor.

Before we get all happy and high fiving (or predicting the end of Man) note that the DNA helix (a simple structure of 6 nucleotides) had to be inserted into a previously living cell with an active life force. The cell wall and all the internal components of a single cell organism are mind bendingly complex.

 

 

Imagining that all the information needed to create a complex life form (viruses are easier) is contained in the DNA was always a fallacy.  A great deal of the needed information is located in the structure of the cell, which the DNA never leaves.  Cell growth, division, and differentiation are molded by interactions with the environment and other cells.  DNA synthesizes proteins in response to the chemical conditions of the cell, to signals it receives from outside the nucleus, and to stimuli provoked by organelles.

 

By itself, a strand of DNA wouldn't know which genes to turn on or off when, and would get no feedback to regulate its activity.

 

Mind bendingly complex, life is.  But not incomprehensibly so.  


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#69 gnowellsct

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Posted 25 June 2019 - 04:01 PM

I did not know about water on Titan. Thanks for the info.

Don't forget the Europa Report (movie).  Spooky squid.



#70 InkDark

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Posted 26 June 2019 - 09:59 AM

Imagining that all the information needed to create a complex life form (viruses are easier) is contained in the DNA was always a fallacy.  A great deal of the needed information is located in the structure of the cell, which the DNA never leaves.  Cell growth, division, and differentiation are molded by interactions with the environment and other cells.  DNA synthesizes proteins in response to the chemical conditions of the cell, to signals it receives from outside the nucleus, and to stimuli provoked by organelles.

 

By itself, a strand of DNA wouldn't know which genes to turn on or off when, and would get no feedback to regulate its activity.

 

Mind bendingly complex, life is.  But not incomprehensibly so.  

Yes, but where would be the cell without DNA?

 

As I understand, the gene produce the cell and organism for its own reproduction. As it have been said: "The chiken is the best way the egg found to produce another egg."   



#71 dgordontx

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Posted 26 June 2019 - 10:25 AM

I'm not sure if these announcements are for publicity or if it's just because so many book-smart people lack common sense and an ability to look at the big picture.



#72 kksmith

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Posted 27 June 2019 - 05:14 AM

I like how they toss around the term "habitable". Habitable is being able to step outside, take the helmet off,  breath, AND live. Shorts, t-shirt, flip-flops or Sorels, touque, choppers, and a parka. But if you have to continuously wear a life support system - it ain't habitable.

 

Ken



#73 Araguaia

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Posted 27 June 2019 - 06:12 AM

No, habitable would be for any life form.  The ocean on Earth is habitable, but you can't take your mask and regulator off and breathe in it.




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