1389: "Surface Area"

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bigmyk2k
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Re: 1389: "Surface Area"

Postby bigmyk2k » Wed Jul 02, 2014 1:24 pm UTC

So, I'm not at all a space nerd, but I still hope I'm not the only one to be surprised that there actually is a Miranda in our solar system...

*insert River Tam picture with your own mind, since apparently my doing so is spam*

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Re: 1389: "Surface Area"

Postby littlebum2002 » Wed Jul 02, 2014 1:25 pm UTC

I'm almost positive Saturn and Jupiter have a small,rocky core. I wonder why they aren't represented.

EDIT: Actually,some research says the core of Saturn is about 25,000km across, which makes it about twice the diameter of earth, and therefore would dominate this picture

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Re: 1389: "Surface Area"

Postby Neil_Boekend » Wed Jul 02, 2014 1:31 pm UTC

bigmyk2k wrote:*insert River Tam picture with your own mind, since apparently my doing so is spam*


It is only spam your first few posts. If you read <a href=http://forums.xkcd.com/viewtopic.php?f=7&t=30124>the rules</a> you'll see why and how many posts.
I do hope that nobody employs PAX to a population in our solar system though.

littlebum2002 wrote:I'm almost positive Saturn and Jupiter have a small,rocky core. I wonder why they aren't represented.

Probably because the size is not known.
It is highly unlikely that they would not have gathered some dust and asteroids in the millions of years they have been milling around and that is completely additional to the current theory that they must have had a core to start gathering all that gas. However, whether that core is of the size of earth or the moon or whatever is not clear.
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Re: 1389: "Surface Area"

Postby Whizbang » Wed Jul 02, 2014 1:41 pm UTC

cellocgw wrote:
Spoiler:
Amazing -- is it the summer heat or what? A whole page of comments and not one about Yo Mama (let alone the surface area covered by Uranus)?

I would have liked to see the surface area of the chrono-synclastic infandibulum in there, but sadly that's somewhat less than solid :oops:


TWSS.

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Re: 1389: "Surface Area"

Postby jpvlsmv » Wed Jul 02, 2014 1:51 pm UTC

For reference, if this comic were printed the size of a standard SD card, the surface of the sun would be 1.5 square meters, or the size of a "square foot garden" that can provide a year's worth of vegetables for one person.

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Re: 1389: "Surface Area"

Postby Spectrum » Wed Jul 02, 2014 1:53 pm UTC

What if you properly accounted for all the small bodies and dust? Does the surface area of smaller objects decline fast enough to counteract their increasing numbers?

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Re: 1389: "Surface Area"

Postby cct » Wed Jul 02, 2014 2:14 pm UTC

It says
Solid Surfaces,
but some of it looks like liquid surfaces. (I realize there is solid under the liquid, but then the boundary differentiating the two kinds of surface is misleading.)

(And, yes, I think it is creepy that randall thinks that this should be done, including all human skin. Is reading XKCD encouraging him?)

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Re: 1389: "Surface Area"

Postby ucim » Wed Jul 02, 2014 2:54 pm UTC

Ool wrote:...Eventually a gigantic cloud of space stations is going to surround the Sun and dim it out...
I'd hate to be the traffic cop of the future.

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Re: 1389: "Surface Area"

Postby Zassounotsukushi » Wed Jul 02, 2014 3:05 pm UTC

I took this comic and measured the relative sizes of the Earth to the two asteroid blocks. This is done by coloring a region in one uniform color in paint. Then I use a histogram tool to count the number of pixels with that color. This gives me a count of pixels in all those regions. Let me share my results. First I have the pixels, then I have the ratio relative to Earth's total surface area, then I have the squared km value.

  • Earth 156110 5.10E+08 100%
  • 1 km 14941 4.88E+07 9.57%
  • 100 m 1236 4.04E+06 0.79%
  • land 38144 1.25E+08 24.43%

For at least the 1 km class, this is relatively consistent with my research. You can use the JPL Small Body search tool to produce cool lists of asteroids. But we don't have data fields for the diameter for most, but they can be estimated using average albedo values and standard methods. Doing this for the main belt asteroids, I get a sum of 4.42e7 squared km, which is 8.66% of Earth's area. This is very close to the comic's value. I did the same thing for objects under 100m, but it doesn't match and it's hard to get a reliable method for that with data. I think the problem is that undiscovered asteroids are very numerous.

But we can delve into the issue a little further and consider even undiscovered tiny asteroids. There are some known correlations for this, of course. I like this one, although the site has since been removed for some reason.

Bottom line is that small asteroid abundances follow a trend of D^-4 for large objects and D^-2.3 for small ones. That is for dN/dD, the differential number given the diameter. Once you convert to surface area, you'll be multiplying by D^2. That means that d(surface area)/dD will follow D^-0.3. Integrate this to get total surface area within a certain diameter range. Say that you're looking at diameters D1 to D2. The total surface area of all asteroids within that range will be (D2^0.7 - D1^0.7).

Theoretically, this is quite weighty. It implies that there is a finite surface area of all asteroids as you limit to zero size. If this was not the case, you would have to look at molecular limitations. But even without that, it seems that equations do not predict that asteroids will block out the sun.

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Re: 1389: "Surface Area"

Postby Unclevertitle » Wed Jul 02, 2014 3:12 pm UTC

Klear wrote:So... anybody still thinks Pluto should be a planet? =P

Well at least it's bigger than Australia.

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Re: 1389: "Surface Area"

Postby arto7 » Wed Jul 02, 2014 3:17 pm UTC

the interweb wrote:Venus's atmosphere is nearly a hundred times thicker than Earth's, and because it's 96% Carbon Dioxide, the planet has a massive greenhouse effect. Can you think of a way to get rid of most of a planet's atmosphere to reduce the temperature enough so water stays liquid? Then there's the other 4% of Venus's atmosphere which contains some really nasty gasses like Sulfur Dioxide, Carbon Monoxide, Hydrogen Chloride and Hydrogen Flouride. How do we get rid of them?

Mars has a huge amount of carbon dioxide frozen in the ground. Melt that with nuclear reactors to release it, this warms the planet and increases atmospheric pressure enough to allow liquid water on the surface of Mars. Then you add plants to turn CO2 to Oxygen. Easy
Could we start by dumping volcanic vent bacteria on Venus? They feed directly on the nasty stuff I believe, at least the Sulfur Dioxide. Get some other critters for the Hydrogens. Once enough of that is filtered from the atmosphere we add plants. Of course, by the time we are ready to settle there will be some hideous blob descendent of the original bacteria waiting for us. Hungrily.

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Re: 1389: "Surface Area"

Postby Minerva » Wed Jul 02, 2014 3:27 pm UTC

I think it would be really cool to show the portion of Titan's surface area which is covered by its rivers and oceans.
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Re: 1389: "Surface Area"

Postby Zassounotsukushi » Wed Jul 02, 2014 3:33 pm UTC

arto7 wrote:
the interweb wrote:Venus's atmosphere is nearly a hundred times thicker than Earth's, and because it's 96% Carbon Dioxide, the planet has a massive greenhouse effect. Can you think of a way to get rid of most of a planet's atmosphere to reduce the temperature enough so water stays liquid? Then there's the other 4% of Venus's atmosphere which contains some really nasty gasses like Sulfur Dioxide, Carbon Monoxide, Hydrogen Chloride and Hydrogen Flouride. How do we get rid of them?

Mars has a huge amount of carbon dioxide frozen in the ground. Melt that with nuclear reactors to release it, this warms the planet and increases atmospheric pressure enough to allow liquid water on the surface of Mars. Then you add plants to turn CO2 to Oxygen. Easy
Could we start by dumping volcanic vent bacteria on Venus? They feed directly on the nasty stuff I believe, at least the Sulfur Dioxide. Get some other critters for the Hydrogens. Once enough of that is filtered from the atmosphere we add plants. Of course, by the time we are ready to settle there will be some hideous blob descendent of the original bacteria waiting for us. Hungrily.


I do tire of reading all the ideas for terraforming Venus that lack reference to actual physical values. If you're talking about a purely atmospheric bacteria, then even if we could engineer such an organism, they have a major purity problem that people don't often talk about. Life on Earth often requires water, and the ingredients are horribly absent on Venus. There's very little Hydrogen, for one.

You could certainly sequester the CO2, but the problem is that... you need to sequester C and O. How? We can make large carbon blocks of a variety of forms. Again, the problem is that the content of other elements must be kept within the parts per million range in order to keep those elements available for your standing population of bacteria. That also limits the total number of bacteria you can have because there's a huge premium on these things. But even if the Carbon falls to the surface in graphite blocks, what form does the Oxygen wind up in? No really, I'm asking you. Where does the Oxygen from the CO2 go? I can't figure it out. If you make O2 gas, the planet will end up just as uninhabitable as it started out.

Alternative Proposal

So let me offer a certain way of thinking that I believe can work. Build large flexible tubes. These will be like 8 km long and many meters in diameter, but they don't need to be rigid. Now, have a floatie on one end. Once you're in the Venus atmosphere, you deploy the floatie bags and let the rest of the tube's length dangle down to lower altitudes. Now, you have a giant straw standing straight up in the atmosphere. You might have a fan to start the flow, but once you have a flow from the bottom to the top, natural circulation will continue this indefinitely. You can even extract power from it.

Why? Because if you continue this plan long enough, you can homogenize the atmosphere's temperature with no energy input. Once you do that, the surface becomes workable with robots and some organisms. Now, you can bring the regolith material into your material balance, bonding the extra atmospheric elements with various minerals. Then, over a much longer time, you can decrease the atmosphere pressure.

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Re: 1389: "Surface Area"

Postby rcox1 » Wed Jul 02, 2014 3:48 pm UTC

littlebum2002 wrote:I'm almost positive Saturn and Jupiter have a small,rocky core. I wonder why they aren't represented...

I am ok with leaving Jupiter and Saturn out because the intent of the comic was to depict solid surfaces. Earth has a lot of solid surfaces, including mostly underneath the water. On the other hand, we don't know if the core of Jupiter or Saturn is really solid. The temperatures and pressures at the hypothetical point at which a surface might be present is really beyond what we have studied or can create in a lab. There is probably a core, it is probably many times the diameter of the Earth and may constitute much of the mass in the solar system. But whether there is a solid surface is speculation.

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Re: 1389: "Surface Area"

Postby orthogon » Wed Jul 02, 2014 4:02 pm UTC

jpvlsmv wrote:For reference, if this comic were printed the size of a standard SD card, the surface of the sun would be 1.5 square meters, or the size of a "square foot garden" that can provide a year's worth of vegetables for one person.

So a "square foot garden" is over 16 square feet? That's inflation, I suppose... That, or marketing.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1389: "Surface Area"

Postby DanD » Wed Jul 02, 2014 4:12 pm UTC

Patteroast wrote:As for Mars colonization, keep in mind that there aren't oceans covering 70% of its surface. For dry land area we end up about equal.


But does it remain that way after terraforming?

http://what-if.xkcd.com/54/
Last edited by DanD on Wed Jul 02, 2014 4:16 pm UTC, edited 1 time in total.

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Re: 1389: "Surface Area"

Postby DanD » Wed Jul 02, 2014 4:15 pm UTC

Dyolf_Knip wrote:I don't really understand the appeal of planet colonization myself. You go through an incredible amount of trouble to hoist yourself and your vehicle out of a gravity well, move it umpteen millions of miles... and then promptly drop it down another one, into an environment you can exercise only minimal control over? Nuts to that. You want to colonize space, then colonize space.


Gravity. To the best of out understanding, humans, especially the newly developing ones really like gravity. They also like atmospheres that don't disappear during accidents and built in radiation shielding (not that Mars is great on that, but it's better than Ceres), little things like that.

I'm not saying that I don't agree that space habitats are probably the way to go (and provide a lot of promise for eventual interstellar colonization), but there are a lot more problems to be solved with them than there are with Mars.

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Re: 1389: "Surface Area"

Postby Moose Anus » Wed Jul 02, 2014 4:19 pm UTC

Is this in Mercator projection?
Lemonade? ...Aww, ok.

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Re: 1389: "Surface Area"

Postby orthogon » Wed Jul 02, 2014 4:25 pm UTC

Moose Anus wrote:Is this in Mercator projection?

How dare you?!
Anyway, no, because Antarctica is of finite size.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1389: "Surface Area"

Postby operagost » Wed Jul 02, 2014 4:41 pm UTC

Klear wrote:So... anybody still thinks Pluto should be a planet? =P

Then Jupiter, Uranus, and Neptune shouldn't be planets, because they're gaseous.

Or maybe Jupiter's too big.

Or maybe Saturn and Uranus should be excluded because they have rings.

Or maybe Uranus should be renamed because you can't pronounce it in any manner that doesn't produce laughter.

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Re: 1389: "Surface Area"

Postby orthogon » Wed Jul 02, 2014 4:55 pm UTC

operagost wrote:
Klear wrote:So... anybody still thinks Pluto should be a planet? =P

Then Jupiter, Uranus, and Neptune shouldn't be planets, because they're gaseous.

Or maybe Jupiter's too big.

Or maybe Saturn and Uranus should be excluded because they have rings.

Or maybe Uranus should be renamed because you can't pronounce it in any manner that doesn't produce laughter.

For some reason this reminded me of Randy Newman's classic Political Science, specifically this verse:
Randy Newman wrote:Asia's crowded and Europe's too old
Africa is far too hot
And Canada's too cold
South America stole our name
Let's drop the big one
There'll be no one left to blame us

I imagine some crazed president enacting Newman's proposal and then continuing to the logical next step of launching Inter-Planetary Ballistic Missiles to take out all those annoying planets too.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1389: "Surface Area"

Postby BlueNight » Wed Jul 02, 2014 5:07 pm UTC

As a Doom player, I was initially disappointed that Phobos and Deimos weren't on here, but then I remembered that they are "small rocks": 1,500 km^2 and 500 km^2. By comparison, the smallest labelled bodies on the chart are Miranda and Vesta, at 700,000 km^2 and 800,000 km^2.

eran_rathan wrote:@Phorrest - Regarding Venus, the upper atmo is pretty habitable - its just a matter of figuring out how to stay up there all the time (breathable air mixes are a lifting gas in Venus's atmo, so that helps).

Or, if we were going that route, bombardment of Venus with large amounts of water-ice comets and seeding it with extremophiles could terraform it to habitability with moderate effort (though granted, more effort than it would take to terraform Mars).


What if we bioengineer different lifeforms for different stages?
What if they all adapt over time to the changing conditions?
What if the resulting habitable planet has vast forests between colony towns, inhabited by the adapted extremophiles?
What if the colonists' kids can catch and train them?

Let's make a Pokemon planet out of Venus! Go, Team Rocket!
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Re: 1389: "Surface Area"

Postby Moose Anus » Wed Jul 02, 2014 5:18 pm UTC

operagost wrote:Or maybe Uranus should be renamed because you can't pronounce it in any manner that doesn't produce laughter.
Your anus. Urine us. Just call it dickbutt.
Lemonade? ...Aww, ok.

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Re: 1389: "Surface Area"

Postby Pfhorrest » Wed Jul 02, 2014 5:27 pm UTC

operagost wrote:Or maybe Uranus should be renamed because you can't pronounce it in any manner that doesn't produce laughter.

The Ancient Greek way works fine for me. "Ooh-ran-os". It's neither poopy like your anus nor pissy as in urine-ous. It's exciting: "ooh! ran-os!"
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Re: 1389: "Surface Area"

Postby SecondTalon » Wed Jul 02, 2014 5:33 pm UTC

Blackfoot wrote:What is the extra space around the Earth land area? Can't be the oceans, as this is solid surface only.
cct wrote:It says
Solid Surfaces,
but some of it looks like liquid surfaces. (I realize there is solid under the liquid, but then the boundary differentiating the two kinds of surface is misleading.)


Solid in the "Not gaseous" sense, not solid as in "dry land" sense.
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Re: 1389: "Surface Area"

Postby JudeMorrigan » Wed Jul 02, 2014 6:14 pm UTC

cellocgw wrote:Amazing -- is it the summer heat or what? A whole page of comments and not one about Yo Mama (let alone the surface area covered by Uranus)?

I heard they were going to change the name to Urectum to avoid those jokes.

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Re: 1389: "Surface Area"

Postby Dyolf_Knip » Wed Jul 02, 2014 6:26 pm UTC

Ool wrote:Eventually a gigantic cloud of space stations is going to surround the Sun and dim it out, capable of containing many trillions and quadrillions of people.


This, by the way, was the actual notion of a Dyson Sphere. Not a single, rigid, monolithic construct, but a swarm of smaller orbiting bodies collectively blocking out the sun.

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Re: 1389: "Surface Area"

Postby Klear » Wed Jul 02, 2014 6:32 pm UTC

Re: Colonizing Mars instead of Venus - it's great that with a lot of effort we could probably come up with an expensive plan how to terraform it at least a little bit over several decades, but we can fly to Marx now.

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Re: 1389: "Surface Area"

Postby Dyolf_Knip » Wed Jul 02, 2014 6:37 pm UTC

DanD wrote:To the best of out understanding, humans, especially the newly developing ones really like gravity. They also like atmospheres that don't disappear during accidents and built in radiation shielding (not that Mars is great on that, but it's better than Ceres), little things like that.


The gravity issue is a problem to be overcome, not a reason to tie yourself down to a planet. It's not like we don't know how to simulate it, either. It's just a question of having sufficient resources to build habitats big enough to spin up to a good chunk of 1G. Which would be much easier to start doing closer to Earth, rather than way the hell out on Mars, where in any event you'd be stuck at 0.38G no matter what.

As you say, no other body in the solar system has the atmosphere thing already taken care of, so it's a problem no matter where you go. As for radiation shielding, I specifically mentioned tunneled-out asteroids. Put 10 meters of rock between yourself and the inky blackness and your dosage will be less than what you'd get standing here on Earth.

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Re: 1389: "Surface Area"

Postby Tyndmyr » Wed Jul 02, 2014 6:51 pm UTC

Dyolf_Knip wrote:
Istaro wrote:Huh. I must admit this makes Mars colonization efforts seem a little less important (not that the eggs-basket argument doesn't still hold). I mean look, we've already got a plurality of the solar system's solid surface area right here.


I don't really understand the appeal of planet colonization myself. You go through an incredible amount of trouble to hoist yourself and your vehicle out of a gravity well, move it umpteen millions of miles... and then promptly drop it down another one, into an environment you can exercise only minimal control over? Nuts to that. You want to colonize space, then colonize space.

Now, if you were to redo this with the surface area of the asteroids after you've gone and honeycombed them out (something not really feasible with higher gravity larger bodies), I doubt you'd even be able to see the rest of the planets on the map.


Fully agree. Planets are a terribly inefficient use of material, and gravity wells are so obnoxious. Time for orbitals.

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Re: 1389: "Surface Area"

Postby Quizatzhaderac » Wed Jul 02, 2014 7:02 pm UTC

Unclevertitle wrote:
Klear wrote:So... anybody still thinks Pluto should be a planet? =P

Well at least it's bigger than Australia.
Australia should have never been a continent! It's just a barren island off the coast of Java!

Interesting point, with Venus it looks like we have too much atmosphere for all the surface area, not too little.

So here's the plan for terraforming:For Earth we cut a little deeper under the oceans so that most of the oceans are only a kilometer deep. Nothing interesting is happening between the photic zones and the floor, and well need the water for other things. We'll cut the other bodies to have at least some shallow oceans to let water move through the whole mess.

We'll figure out just how much of Venus's atmosphere we want and make two cuts for Venus, one below and one above to cut off the extra atmosphere. Same for Titan.

We put the first fence around what's currently Earth. We put some pressure valves at the bottom to let the extra ocean out. To the other areas, we release extremophiles, then algae, then ferns and kelp, and eventually grasses, trees, and pokemon.

Once the other areas are terraformed we start emigrating.

The second fence we'll put around the border of this whole... thing. I'm not sure what the outside is (sea of aether?), but it's probably full of reavers, forgotten beasts, creepers, trollocs, murlocks, pa'anuri, nerve runners, vashda narada, horrorterrors, and hipsters.
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Re: 1389: "Surface Area"

Postby eran_rathan » Wed Jul 02, 2014 7:04 pm UTC

BlueNight wrote:As a Doom player, I was initially disappointed that Phobos and Deimos weren't on here, but then I remembered that they are "small rocks": 1,500 km^2 and 500 km^2. By comparison, the smallest labelled bodies on the chart are Miranda and Vesta, at 700,000 km^2 and 800,000 km^2.

eran_rathan wrote:@Phorrest - Regarding Venus, the upper atmo is pretty habitable - its just a matter of figuring out how to stay up there all the time (breathable air mixes are a lifting gas in Venus's atmo, so that helps).

Or, if we were going that route, bombardment of Venus with large amounts of water-ice comets and seeding it with extremophiles could terraform it to habitability with moderate effort (though granted, more effort than it would take to terraform Mars).


What if we bioengineer different lifeforms for different stages?
What if they all adapt over time to the changing conditions?
What if the resulting habitable planet has vast forests between colony towns, inhabited by the adapted extremophiles?
What if the colonists' kids can catch and train them?

Let's make a Pokemon planet out of Venus! Go, Team Rocket!


I'd like to direct your attention to Podkayne of Mars, circa 1962... ;)
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Re: 1389: "Surface Area"

Postby Zassounotsukushi » Wed Jul 02, 2014 7:12 pm UTC

Dyolf_Knip wrote:
Ool wrote:Eventually a gigantic cloud of space stations is going to surround the Sun and dim it out, capable of containing many trillions and quadrillions of people.


This, by the way, was the actual notion of a Dyson Sphere. Not a single, rigid, monolithic construct, but a swarm of smaller orbiting bodies collectively blocking out the sun.


Even then, it's not a completely physically accurate notion. Just look at the Kardashev scale - the levels of civilization are set to benchmarks in terms of the quantity of energy use. This only makes sense to us right now because we live on Earth, which has a relatively well-defined ambient temperature. The same isn't true for space, and because of that, entropy is a better classifier of their industrial throughput.

In space, you can run a thermal cycle between room-temperature and a radiator. Imagine a solar array harvesting 1 MW of power. Use that power in a space station, and you now have 1 MW of waste heat at roughly 293 Kelvin. Then connect a cryogenic cycle between that space station and a radiator at 4 Kelvin. The theoretical maximum is 98.6% efficiency there. That means that, with no additional solar panels, you could (at least theoretically) increase this from a 1 MW station to a something like a 70 MW station with no additional solar radiance.

The further out you go from the sun, the colder a Dyson Sphere's heat sink could be. Its heat source is a constant temperature set by the surface temperature of the sun. That means the ultimate amount of useful work you could get from a 10 AU Dyson Sphere could be 3 times more than what you'd get from a 1 AU Dyson Sphere. You also won't mess with the solar dynamics by reflecting its own heat back to it so much.

So the most correct picture (based only on energetics) would be sparse habitats dispersed through the interstellar medium, avoiding each other in order to reduce their temperature. Whether the energy source is a sun or fusion, it makes no matter. But perhaps they'll mine rogue planets for the coldness trapped within them.

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Re: 1389: "Surface Area"

Postby Lexi_K » Wed Jul 02, 2014 7:48 pm UTC

How are the surfaces of these objects estimated?
I can imagine that the asteroids and maybe the one or other moon is really, really porous.
If one gram active coal can already reach 1500m² ...
As far as I know, asteroids might be barely more than snow dust around a more or less massive core.

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Re: 1389: "Surface Area"

Postby RFredW » Wed Jul 02, 2014 8:39 pm UTC

Blackfoot wrote:What is the extra space around the Earth land area? Can't be the oceans, as this is solid surface only.


I completely agree that this comic has an odd "liquid counts as solid, but gas doesn't" vibe, and would have preferred a fair fight. Possibly it's tied into events in this week's "What if".

ttfn
Fred

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Klear
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Re: 1389: "Surface Area"

Postby Klear » Wed Jul 02, 2014 8:52 pm UTC

RFredW wrote:
Blackfoot wrote:What is the extra space around the Earth land area? Can't be the oceans, as this is solid surface only.


I completely agree that this comic has an odd "liquid counts as solid, but gas doesn't" vibe, and would have preferred a fair fight. Possibly it's tied into events in this week's "What if".

ttfn
Fred


I believe it's because it's an easy matter to imagine Earth without water, but the gas giant's atmospheres turn continuously into the solid core with the increasing pressure without any clear-cut boundary.

DanD
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Re: 1389: "Surface Area"

Postby DanD » Wed Jul 02, 2014 8:59 pm UTC

RFredW wrote:
Blackfoot wrote:What is the extra space around the Earth land area? Can't be the oceans, as this is solid surface only.


I completely agree that this comic has an odd "liquid counts as solid, but gas doesn't" vibe, and would have preferred a fair fight. Possibly it's tied into events in this week's "What if".

ttfn
Fred


I'm pretty sure if we flatten out the earth into a thin sheet in order to sew it to the others, the water mostly goes away, so the sea floor is now able to support structures. If you do the same thing with a gas giant, the solid core most likely sublimates, resulting in no or minimal planet remaining.

armandoalvarez
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Re: 1389: "Surface Area"

Postby armandoalvarez » Wed Jul 02, 2014 10:07 pm UTC

RFredW wrote:
Blackfoot wrote:What is the extra space around the Earth land area? Can't be the oceans, as this is solid surface only.


I completely agree that this comic has an odd "liquid counts as solid, but gas doesn't" vibe, and would have preferred a fair fight. Possibly it's tied into events in this week's "What if".

ttfn
Fred

It's completely fair to include "the extra space around the Earth land area": there is solid surface directly below our oceans. To discount that solid surface just because it has liquid above it would be like discounting all the surfaces that have atmospheres above them.

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keithl
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Re: 1389: "Surface Area"

Postby keithl » Wed Jul 02, 2014 11:44 pm UTC

Pfhorrest wrote:Someone remind me again why colonizing Venus is totally out of the question? Yeah it's got the runaway greenhouse thing but at least it has an atmosphere and the right gravity and such; since we'd need to reprocess the atmosphere of any planet we wanted to settle, why can't we do Venus?


There are serious proposals for colonizing Venus - but not the surface!

Aerostats filled with oxygen and nitrogen, which is buoyant in CO2. The temperatures are fairly cool high in the Venus atmosphere. You will need to import water, and lots of it, not sure how to deliver that without a lot of pesky delta V. Perhaps there is some bound in the rocks below. All the structural carbon you could ever want, and plants can help you make more.

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MisterH
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Re: 1389: "Surface Area"

Postby MisterH » Thu Jul 03, 2014 12:47 am UTC

Xenomortis wrote:
tomandlu wrote:Do Jupiter and Saturn have no solid surface at all (or am I just going blind)?

Basically, no.
As you descend into Jupiter's atmosphere (or the other gas giants), the pressure keeps increasing. After a while, the gas surrounding you starts becoming more and more liquid like (and eventually you might hit some exotic ices).


Until you land on a lump of metallic Hydrogen and if we're not allowing that because it's sloshing about, why has Randall included the Earth's oceans?


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