# Comets proven to contain the building blocks of life



## Brian G Turner (May 28, 2016)

Building blocks of life spotted around comet for the first time



> A frosty comet could have delivered the ingredients for life to Earth. The European Space Agency’s Rosetta spacecraft has spotted an amino acid on the comet it orbits – confirming that a ball of ice and dust can hold a major building block of life.
> 
> Amino acids are the building blocks of proteins, which control essential reactions in living cells. Astrobiologists have long wondered whether they could have been delivered to early Earth on the backs of comets or asteroids.
> 
> ...


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## Vertigo (May 28, 2016)

> A frosty comet could have delivered the ingredients for life to Earth


But how much more likely are they to have simply evolved on Earth (as well)? Why must they have been delivered to Earth from comets? Just because we find amino acids on comets doesn't mean that's the only place the might have formed.


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## Ray McCarthy (May 28, 2016)

Vertigo said:


> Just because we find amino acids on comets doesn't mean that's the only place the might have formed.


I agree. The only significance is that they [amino acids] might have formed anywhere suitable. I've never understood why some people want it to be proved that life came from somewhere else. That's ultimately a "There are turtles all the way down" argument.

I think it's likely that if life is a natural phenomenon rather than "special creation" then it must have happened already on maybe over 50,000 worlds in the Galaxy, separately, independently. Amino acids aren't life anyway. It's a nutty idea that somehow it's more likely to have originated here from comets than separately.


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## Dennis E. Taylor (May 28, 2016)

Vertigo said:


> But how much more likely are they to have simply evolved on Earth (as well)? Why must they have been delivered to Earth from comets? Just because we find amino acids on comets doesn't mean that's the only place the might have formed.



The way I look at it (and used this in my current book) is that the organics were floating around space when the Earth was just forming, and were falling onto Earth long before it had cooled to the point where the organics could survive. By the time Earth cooled sufficiently, and was ready for organics to evolve domestically, the blow-ins had already been raining down for ages. It's theoretically possible that, left to its own devices, the Earth might have evolved _different_ organics, but there was no opportunity.


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## Vertigo (May 28, 2016)

I see where you're coming from but it seems to me that virtually everything in our solar system will have come from the same cloud that our sun was formed from. Possibly some stuff has been captured from beyond that cloud but relatively vanishingly small amounts I believe. Therefore pretty much everything has the same antiquity. I imagine there's some variation in when each planet formed but probably not much compared to the age of the solar system. So why should organics have formed more quickly in space than on Earth? I just don't see any strong argument for it. And even if some did come from space the likelihood is that far more formed on Earth. Note formed not evolved - organics are just chemicals they're not life and certainly wouldn't prevent the formation of other organic chemicals. There's no kind of competition going on at this stage.


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## J Riff (May 28, 2016)

Obviously, all life came from somewhere else. This particular planet we wander about on was formed millions, nay billion of years after zillions of others.
Unlest we assume they were all dead... and only Earth fluked out with the life stuff.. then we are not from around here!
- A. Lien


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## Ray McCarthy (May 28, 2016)

J Riff said:


> Obviously, all life came from somewhere else


Why?
That's like saying the Earth rests on a turtle. It answers no questions and is less likely and you still have the same problem of how did it start. The comets don't travel interstellar distances. The interstellar distances are a quite effective quarantine zone. There are billions of stars just in our own galaxy.



So what holds up the turtle?

Another turtle, it's turtles all the way down.


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## J Riff (May 28, 2016)

Oh geeee... a trillion planets and no life that drifts outward with the billions of explosions going on? We underrate this galaxy. Humans, way out here in the sticks, may be the most blinkered of all (intelligent) lifeforms extant.
I think you are right about nothing floating or drifting in for aeons, but the odds of life not forming elsewhere are microscopic, laughable. We aren't anything unusual, life fights it's way onward and upward, absolutely anywhere that it can. Spores floating through space, perhaps? Yes, gotta be true - there have to be creatures adapted to survival in space. What a waste of space it would be otherwise.


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## Ray McCarthy (May 29, 2016)

J Riff said:


> but the odds of life not forming elsewhere are microscopic, laughable. We aren't anything unusual,


which is why I said


Ray McCarthy said:


> I think it's likely that if life is a natural phenomenon rather than "special creation" then it must have happened already on maybe over 50,000 worlds in the Galaxy, separately, independently.


Either life is an inevitable natural process, or starts by "creation" by God. Either way there is no reason to suppose that Earth is unique.

Eventually spectroscopic analysis with bigger space telescopes, maybe the "James Webb", will show us planets that not only have life but maybe have industrialisation.
Unless starships are possible we can only barely "visit" our own doorstep.



J Riff said:


> Spores floating through space, perhaps?


It's not like sea or air. There in no medium in which to float.
It takes about 16 days for light from our sun to reach beyond the very far off Kuiper belt. The nearest star is approximately twice the 1000 times further away distance of the Oort Cloud, a very very low density region of lumps  of ice and rocks, not actually a cloud. If you were travelling to Alpha Centauri you'd not notice the Oort Cloud, there is so little material relative to its own diameter of about 2 light years on average. The next star is a MILLION times the Earth - Sun distance away.

Logarithmic scale. Each step right is TEN times distance.
Oort cloud - Wikipedia, the free encyclopedia

We are in a low density "bubble" in space possibly caused by a supernova very long ago. It's about 300 Light years across.
Local Bubble - Wikipedia, the free encyclopedia

Where are we?


> There is speculation that the local spur known as the Orion–Cygnus Arm, which includes the Solar System and Earth and is located inside of Perseus Arm, is a branch of it, but this is unconfirmed.
> ...
> Within the Orion Arm, the Solar System, including Earth, is located close to the inner rim in the Local Bubble, about halfway along the Orion Arm's length, approximately 8,000 parsecs (26,000 light-years) from the Galactic Center.


We aren't in the "backwoods" as the Milky Way, our galaxy is 100,000 to 180,000 Light Years in diameter (we can't see it clearly enough to be sure of size  being inside it).  So we are about 1/4 to 1/6th of the distance from centre to edge of the galaxy.
The space between stars is very large and between clusters is huge. Even the "darker" parts which give the effect of seeing spiral arms are full of stars.

We are part of a local galactic group
File:5 Local Galactic Group (ELitU).png - Wikipedia, the free encyclopedia

Position in observable universe
File:Earth's Location in the Universe (JPEG).jpg - Wikimedia Commons

Just the observable universe has a mind boggling number of galaxies, each with an incomprehensible number of stars. Even if each planet with life was 1000 light years apart, there could still be millions of planets with life in our own galaxy. We don't know. Nor do we know how often a planet with life results in a civilisation, or how long one can last (our oldest archaeological records suggest we have been building towns for nearly 10,000 years). The dinosaurs don't seem to have had a culture or civilisation, but did last about a million years, I think.


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## Vertigo (May 29, 2016)

Dinosaurs were Earth's dominant life form for around 135 million years. Which is one of the reasons why I'm sceptical about our level of intelligence being the inevitable logical conclusion of life. Dinosaurs didn't need it so didn't evolve it. At least not beyond that needed by a smart predator.



J Riff said:


> Obviously, all life came from somewhere else. This particular planet we wander about on was formed millions, nay billion of years after zillions of others.
> Unlest we assume they were all dead... and only Earth fluked out with the life stuff.. then we are not from around here!
> - A. Lien


If all life came from somewhere else then where did _*that*_ life come from. And so on...


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## Ray McCarthy (May 29, 2016)

Vertigo said:


> Dinosaurs were Earth's dominant life form for around 135 million years


Just shows that having a civilisation isn't needed for longevity of a species. That's a LONG innings!

I agree that it's possible a tiny proportion of planets with life may ever have a civilisation. Even if it was only 1:100,000 planets with life there might still be 1,000 to 50,000 civilisations right now, with a tiny proportion of those being industrialised. Till we have better spectroscopic surveys we can only guess. We can't know if there are 100,000 or a 100 million planets (still maybe less than 1:1000 planets!) with some form of life right now. We don't have the information. Perhaps life is rare and a civilisation (even without industrialisation) very much rarer.

The Milky Way contains between 200 and 400 billion stars and at least 100 billion planets. The exact figure depends on the number of very-low-mass stars, which are hard to detect, especially at distances of more than 300 light years from the Sun. That 300 LY is about 0.0008% of the Milky Way's stars!
Every time we get better telescopes we revise the estimates upwards! There are likely to be more than 100,000,000,000 planets in our own Milky Way. The current best estimate is that the OBSERVABLE universe has 100 Billion  galaxies. Some bigger, some smaller than ours. So even if there was only 10 planets with life of ANY sort, (which would then be statistically maybe 10,000 light years apart!), there might then be 1 Million, Million planets with life in the observable universe.

Really we are a less than a speck in the observable universe and hardly likely to be unique?




Vertigo said:


> If all life came from somewhere else then where did _*that*_ life come from. And so on...


The Turtles thing...


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## Cathbad (May 29, 2016)

Ray McCarthy said:


> Either life is an inevitable natural process, or starts by "creation" by God.



It has always intrigued me that these "two" possibilities are thought to be unique to each other.  Why cannot both be true?  After all, God didn't explain _how_ he did it!


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## Ray McCarthy (May 29, 2016)

Cathbad said:


> Why cannot both be true?


That would cover two "theologies":
1) God as Clockmaker.
2) God influencing which of many possible evolutions wins.
Purely evolution with no god and "Special" creation by a god are the two most opposed views.


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## Vertigo (May 29, 2016)

Ray McCarthy said:


> Just shows that having a civilisation isn't needed for longevity of a species. That's a LONG innings!
> 
> I agree that it's possible a tiny proportion of planets with life may ever have a civilisation. Even if it was only 1:100,000 planets with life there might still be 1,000 to 50,000 civilisations right now, with a tiny proportion of those being industrialised. Till we have better spectroscopic surveys we can only guess. We can't know if there are 100,000 or a 100 million planets (still maybe less than 1:1000 planets!) with some form of life right now. We don't have the information. Perhaps life is rare and a civilisation (even without industrialisation) very much rarer.


This is my suspicion and then you must ask what the expected life of a civilisation is likely to be. The jury's out on this particular example...



Ray McCarthy said:


> The Milky Way contains between 200 and 400 billion stars and at least 100 billion planets. The exact figure depends on the number of very-low-mass stars, which are hard to detect, especially at distances of more than 300 light years from the Sun. That 300 LY is about 0.0008% of the Milky Way's stars!
> Every time we get better telescopes we revise the estimates upwards! There are likely to be more than 100,000,000,000 planets in our own Milky Way. The current best estimate is that the OBSERVABLE universe has 100 Billion  galaxies. Some bigger, some smaller than ours. So even if there was only 10 planets with life of ANY sort, (which would then be statistically maybe 10,000 light years apart!), there might then be 1 Million, Million planets with life in the observable universe.
> 
> Really we are a less than a speck in the observable universe and hardly likely to be unique?


I get a bit twitchy about counts of planets. The vast majority of stars in any galaxy are naturally concentrated around the centre where exactly that concentration results in huge levels of radiation making any life that relies upon reliable replication extremely unlikely. And without consistent replication you would have chaos not life. So the actual count of star systems in our galaxy where life is possible is almost certainly a tiny proportion of the actual number of star systems.




Ray McCarthy said:


> The Turtles thing...


Precisely!


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## Ray McCarthy (May 29, 2016)

Vertigo said:


> The vast majority of stars in any galaxy are naturally concentrated around the centre where exactly that concentration results in huge levels of radiation


Is it really more than half? We are only 1/4 to 1/6th of the way out between GC and "edge". Also the bigger risk before you are close enough to GC is getting wiped out by a super nova, but then there are a lot of stars there not disrupted by supernova.

I'd say any current estimate of number of planets and number of planets that might be suitable for life is pretty speculative till we have better observations. It's likely much more than was thought 50 years ago, but then people didn't actually know if ANY other star had a planet!

We only have a sample of one out of maybe 400 billion stars to examine closely!



Vertigo said:


> So the actual count of star systems in our galaxy where life is possible is almost certainly a tiny proportion of the actual number of star systems.


A tiny proportion still might be a relatively large number, but we won't know till we get better observations. 

At any rate the various newspaper headlines about "Life from comets" are a bit misleading. Not impossible but seems less likely than local development on each planet. If some watery moon of Jupiter is discovered with microbes, that will be interesting. Currently Mars seems unlikely.


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## Vertigo (May 29, 2016)

It is of course hugely speculative but this is the wiki page discussing it (there are many others) File:Milky Way galactic habitable zone.gif - Wikipedia, the free encyclopedia

Also I think the sun is a bit farther out than you suggest. As I understand it the galaxy is approx 30 kpc diameter so about 15kpc radius and we are about 8 kpc from centre so just over half way out.


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## K. Riehl (May 29, 2016)

Vertigo-"I get a bit twitchy about counts of planets. The vast majority of stars in any galaxy are naturally concentrated around the centre where exactly that concentration results in huge levels of radiation making any life that relies upon reliable replication extremely unlikely. And without consistent replication you would have chaos not life. So the actual count of star systems in our galaxy where life is possible is almost certainly a tiny proportion of the actual number of star systems."

Life as we know it couldn't evolve in a high radiation area. That doesn't mean something that looks on radiation as food/power couldn't evolve. It would be almost incomprehensible to our version of "life" but I am not going to rule out that entire section of space as a possible search area once we develop intergalactic space probes.;-)


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## Vertigo (May 29, 2016)

K. Riehl said:


> Vertigo-"I get a bit twitchy about counts of planets. The vast majority of stars in any galaxy are naturally concentrated around the centre where exactly that concentration results in huge levels of radiation making any life that relies upon reliable replication extremely unlikely. And without consistent replication you would have chaos not life. So the actual count of star systems in our galaxy where life is possible is almost certainly a tiny proportion of the actual number of star systems."
> 
> Life as we know it couldn't evolve in a high radiation area. That doesn't mean something that looks on radiation as food/power couldn't evolve. It would be almost incomprehensible to our version of "life" but I am not going to rule out that entire section of space as a possible search area once we develop intergalactic space probes.;-)


Oh I agree, I wouldn't rule it out, I just consider it highly unlikely. Consider the damage (highly unpredictable damage) radiation does to molecules. Then consider that life of any form is almost certainly going to comprise complex molecules (Simple molecules just don't contain sufficient information to make life plausible). Then consider that it surely will require level of stability and repeatability and I have to say that any model of life imaginable becomes highly unlikely (I believe most scientists agree on this). I'm not saying it's impossible - how could I say that - but I do think it is highly unlikely. Complex molecules are just too vulnerable to such radiation. Whether it be simply from the concentration of stars or the increased frequency of supernovas. The whole idea of a life form that feeds off radiation is I think hugely unlikely though I'm not saying impossible.

I think it's fair to say that the general consensus is that any form of life imaginable is highly improbable in the centre of the galaxy. And the outer reaches of the galaxy are very poor in heavier elements which also makes the formation of the complex molecules required for life highly unlikely.


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## Ray McCarthy (May 29, 2016)

Vertigo said:


> As I understand it the galaxy is approx 30 kpc diameter so about 15kpc radius and we are about 8 kpc from


Our sun 8.34 ± 0.34 kpc
MW 31–55 kpc  (possibly larger, no sharp edge, another Star Trek myth!)
I guess I forgot to divide by two, for radius vs Diameter, my figures above are x2   Sorry.



Vertigo said:


> Consider the damage (highly unpredictable damage) radiation does to molecules.


Which why it's suggested an iron core is needed, so there is a Magnetosphere, to deflect solar radiation.
We might argue also that plate tectonics are a good idea and a decent moon for tides.  It seems anyway that moons might be two a penny and a reasonable sized planet on a second generation star might have an iron core anyway.

I find it a fascinating subject, no matter how many restrictions you put, even places like here might still be a significant number even if a tiny proportion of the galaxy's stars.



Vertigo said:


> that the general consensus is that any form of life imaginable is highly improbable in the centre of the galaxy. And the outer reaches of the galaxy are very poor in heavier elements which also makes the formation of the complex molecules required for life highly unlikely.


There maybe a Galaxy level "goldilocks" zone, though perhaps "much less likely to improbable" closer to GC and progressively less likely, but not impossible as you get nearer the rim, as at outer edges there maybe older stars from passing galaxies and all we know about is life here. But you probably need carbon, oxygen and Iron as well as some other heavier elements, though you might not need them in the proportions we have.


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## Vertigo (May 29, 2016)

Oh I agree absolutely it is a fascinating topic whose waters have been frankly very muddied by an awful lot of pulp SF...

A magnetosphere is no doubt useful (though I believe less so than was once thought). The stabilising effect of our moon is certainly useful but it does require a massive moon which is I think thought to be somewhat less common. Plate tectonics are also useful but I suspect they are tied to the magnetosphere since both require (I think) an active molten core. Other things that I'm sure are also useful would be a relatively non erratic orbit around the sun and possibly, though this is much debated, a few gas giants to shepherd most of the unused debris from the original dust cloud into nice discrete zones.

I agree there are still a huge number of potential candidates but the one thing we really don't know is just how likely the actual creation of life is. It appears to have happened only once here on Earth as all life shares the same structure and we have still not really managed to create it ourselves. We've managed to modify it but not actually create any new life (I think). And if it's that hard to do then that is why I debate (not assert!) how often it will happen/has happened by pure chance. Going from amino acids to molecules that can reproduce is a HUGE step.


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## Ray McCarthy (May 29, 2016)

Vertigo said:


> It appears to have happened only once here on Earth as all life shares the same structure and we have still not really managed to create it ourselves


It could be at that at the basic level /lowest level there is only one way to do it.
*At a higher level we have*
Horse shoe crabs, octopus and other creatures not using iron based blood.
Monotremes, marsupials, avians (descendants of some dinosaurs), sharks vs regular fish, aquatic mammals, coconut crabs that drown in water,
Different schemes for sex chromosomes, higher creatures that can decide to reproduce without sex, bizarre greenfly reproduction, fish that change sex.
Convergent Evolution (Gliding Marsupials like gliding mammals, marsupials like cats and dogs and bears), Panda with non-thumb, thumb.

My theory is that with similar environments, you'll have "fish", "birds", "reptiles", "mammals," "marsupials", "monotremes", "grasses", "bushes", "trees" on alien worlds that at first glance SEEM similar, but actually,  biologically are not similar at all.

We can presume that copper based rather than iron based blood is only an advantage in deep water or cold environments. Silicon life despite SF & Star trek is probably impossible. A bunch of organic style chemicals is the limit. The Chemistry & Physics isn't possible. Any ammonia cycle or such is very speculative indeed, so most likely somewhere with a temperature range -5C to +50C, carbon based and oxygen breathing for anything with legs or big enough for us to see without a magnifying glass. There are some pretty weird algae, bacteria and simple stuff, (thermal vents under sea with arsenic, sulphur. Or boiling salty lakes or frozen wastes) but anything more than water bears (and they "sleep out" hazards by shutting down) is much less exotic in what it copes with.

Anywhere very "hostile" might reasonably have very simple organisms. I'd be surprised if anything more "evolved" isn't more ordinary biochemistry. I don't think it's a lack of imagination, we know a lot more about biochemistry than 50 years ago. Some scenarios seem to have gone speculative->unlikely->impossible as we have learned more. From an evolutionary point of view a creature able to switch between two sexes and parthogenic reproduction is incredibly more likely than a creature needing 3 or more sexes, such a creature can't compete.

Similarly there seems to be a physical reason as a creature is bigger; to go from 6 to 4 (or 2 + wings) limbs, to have bilateral symmetry, mostly have two sexes (but able to reproduce with out, birds and reptiles and fish can anyway, not recorded with mammals, monotremes or marsupials, mice trials not very successful), a head at one end with two eyes, rather than say eight of a spider, etc. Hands with method to grip has arisen quite separately.


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## Vertigo (May 29, 2016)

You list all the same reasons why I don't expect too many surprises if we ever do find other life. For example, as you say our experience seems to suggest more than four limbs simply isn't practical on larger organisms. If it was we would have seen (successful) examples of it in the history of life on Earth. Life even experimented with 6 digits we be reverted to five. I think we would see an awful lot of parallel evolution.

However if it's correct, as has been speculated, that our high (? ) intelligence was only a chance by product of needing a better cooling system then high intelligence may just be an expensive fluke that we got away with.


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## Ray McCarthy (May 29, 2016)

If similar life is found elsewhere, it changes nothing ...
Evolution supporters will say: Ah really we expected it to be the same, convergent evolution and at the most basic level everywhere has same chemistry and physics.
Those believing in "Special Creation" will say, "Well 'He' did it here, so 'He' can do it there"

Really it would be very odd if everything isn't similar (to a degree) everywhere.


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## Ray McCarthy (May 29, 2016)

Vertigo said:


> high intelligence may just be an expensive fluke that we got away with


it's a very mysterious thing. I've been musing about "teaching" a computer to play music and card games, an "idiot savant" program. Subject for another thread.


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## J Riff (May 29, 2016)

Polarized thinking sure doesn't work so well when gabbing about Galaxies... this/that.. and/or a million other chance occurences. Advanced ETs that change all the rules. Nobody thinks there's ETs around? in a SFF writer-based site? Well that's a good thing, because if stuff that's as amazing as our imaginations shows up, we are out of work. *
Oop sorry, did I refer to writing as 'work'.. that thing that people get paid for? *


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## Stephen Palmer (May 30, 2016)

A new book on the origins of life on Earth was published this year. It is fantastic and I recommend it to you all!


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## Ray McCarthy (May 30, 2016)

J Riff said:


> Nobody thinks there's ETs around? in a SFF writer-based site? Well that's a good thing, because if stuff that's as amazing as our imaginations shows up, we are out of work.


a) Makes no difference and opens new opportunities. c.f. inventions of computers (1938-1940s), Rockets (1930s), Mobile Radio leading to Mobile Phones to Smart Phones (1914, 1973, 1998). First proven discovery of exo-planet 1992.
b) Writing, editing etc is real work!
c) SF is  a lot more than speculation about aliens and gadgets. Some of the best has neither.


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## Ray McCarthy (May 30, 2016)

Stephen Palmer said:


> A new book on the origins of life on Earth. It is fantastic


It does sound interesting.


At £7 vs £6 (rounded), I'd buy the paperback. The eBook might  be my choice at £4.99 vs £8.99 for a paperback.  I wish Publishers would offer eBook free with hardcopy, like TicketyBoo does. I can't even see how to do that on Amazon.


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## Vertigo (May 30, 2016)

I probably wouldn't go for the ebook for this one as it has at least some diagrams and I still find them really difficult to study on an eReader (and I don't read on tablets). I find this sort of book works better in printed form.


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## Ray McCarthy (May 30, 2016)

Vertigo said:


> and I still find them really difficult to study on an eReader


I have the 9.7" Kindle DXG and 6.8" Kobo Aura H2O HD, both do diagrams far better than the older 6" kindles. The latest model 6" Kindles are about 300dpi rather than about 200dpi, so are better,* but the 6" models are still often too small for diagrams*. Colour originals may be poor. (I check that images in my eBooks work in mono, though I put them in colour for App users, on the paper books I use higher resolution mono).

I'd agree, I'd get anything with important diagrams as paper. It's only illustrations in fiction that I don't worry about.


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## Vertigo (May 30, 2016)

Yeah I get all tech books in paper (or sometimes both) and, yes, my eReader is an only 6" Sony. When I'm reading books with maps (about to start Andy Weir's Martian) I generally print off copies of the maps for reference, as not only are they difficult to read on the reader (even using zooming the original resolution is usually too low) but it's also a pain to keep going back and forth to them. There is no simple digital equivalent to just sticking your finger in the book to keep your place. Bookmarks, yes, but they're way more fiddly than just sticking your finger between the pages  They'll get there eventually...


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## Ray McCarthy (May 30, 2016)

Vertigo said:


> my eReader is an only 6" Sony


Really OK for text, but unless one of very last models quite poor compared even to 2013 Kindle or Kobo. I nearly bought one in 2007, I think.


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## Vertigo (May 30, 2016)

Yeah it was probably back around then when I bought it. It's getting a bit tired now and I've been thinking of replacing it with a Kobo (won't get Kindle on principle). But we digress...


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## Ray McCarthy (May 30, 2016)

More off topic  ... but



Vertigo said:


> Kobo (won't get Kindle on principle)


kobo has nastier book monitoring and only the expensive 6.8" Aura H2O HD is better than cheaper Kindle 2015 PaperWhite. Calibre can turn off the evil. Kobo are simply less successful than Amazon. Their "push marketing" is evil (Never Sync and only give them a disposable email address via signup on Kobo, don't sign up on Website!) and both need you to enter a working email address to start use. I use via USB only. Amazon are not at all more "evil". The software is slightly more stable on Kindle. Both are similar functionality with Calibre (I put DRM Amazon content on Kobo, and DRM epub on Kindle DXG via Calibre plug ins, only stuff *I* bought!)
If you want diagrams get 6.8" Aura H2O HD, if you want 6" then save money and get Touch (though one version is only 2013 Paperwhite eInk, you want the higher resolution one using same eInk as 2015 PaperWhite). High street shops may have older models.


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## Vertigo (May 30, 2016)

I'm probably looking at the 6" glo, and my principles on Amazon are not just to do with eBooks and monitoring but everything about how they behave. Maybe Kobo would do the same if they had Amazon's dominance, but it's almost a question of me finding that dominance of itself abhorrent. However as I said we digress and it's a topic I have discussed all to often


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## Ray McCarthy (May 30, 2016)

Vertigo said:


> 6" glo,


The H2O HD Aura far better. The glo is a version of Paperwhite 2013 (probably same screen), not even the higher resolution same size PaperWhite 2015.


Vertigo said:


> Maybe Kobo would do the same if they had Amazon's dominance


Worse, just not successful!


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## Vertigo (May 30, 2016)

The glo has a smaller screen (I like the 6") but is 300dpi whereas the H2O HD whilst a larger screen actually has lower resolution at 265dpi. However it's the smaller size I'm interested in. I considered the larger size but, for me, the six inch format is my preference.


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## Ray McCarthy (May 30, 2016)

Vertigo said:


> The glo has a smaller screen (I like the 6") but is 300dp


Ok, so it's a newer HD Glo, Likely same eInk as 2015 PaperWhite and probably similar LED front lights (only needed if you are reduced to candles, oil lamps or nothing in the dark!). That will be fine 
Calibre and USB only transfer is your friend once you register it.

I'd like a 6" eInk with a smaller bezel, thinner is irrelevant, though as I never go anywhere, it doesn't matter. There was a nice Russian phone with LCD on one side and eInk on the other. It would be nice for reading on the go. The Voyage and the Oasis are more expensive than Glo and don't really do anything that the Glo, or PaperWhite do.
They are all very similar software and technology. Keep the Sony to test compatibly of any eBooks you make.


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## J Riff (May 30, 2016)

eReaders proven to contain the building blocks of SFF text ..


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## Ray McCarthy (May 30, 2016)

J Riff said:


> eReaders proven to contain the building blocks of SFF text




Sorry, do not adjust your set. 
Abnormal service and discussion of science and speculative fiction may resume.


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