Science questions not worth a thread I: I'm a moron!

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Mostly it should work, at least for a while. There are some things that won't work at all: As you said the speakers won't work and as the oscillation of the membrane is not damped by air anymore, trying to use them might break them easily. Then the acceleration sensors will not work as intended, because the phone cannot determine its orientation by measuring gravity. This might mess with the user interface or some controls. Last, you are not going to get any signal unless you place a relay nearby.

I don't see any other function that would not work at all, but there will be issues limiting the lifetime of the phone. The first one is heat. Usually the phone is cooled by convection in air, which won't work in a vacuum. If no alternate means of cooling is provided, the phone might overheat quickly. So you would need to cool it somehow.
Then there is radiation. If the electronics are not radiation hardened (and I don't see why the designers should have cared for that) and they are placed outside the van Allen belt they will fail sooner or later due to degradation by radiation. If the phone is supposed to be operated by humans, they will also suffer the radiation, so it would be in their interest to minimize radiation, anyway.
The limiting factor will be outgassing. All materials will slowly evaporate when placed in a vacuum. For most metals this will be very slow, but some polymers have a high outgassing rate. If the rate is too high, the material will evaporate until there is nothing left anymore. And if this material had a critical function, the phone will fail when it's gone. How long this would take depends on the materials used and their function.
I think I recall that there may be a facility or two somewhere that has a room where all the air is sucked out in order to replicate the vacuum of space. I take it the cell phone, if placed in there, would experience a similar situation, but with gravity (and maybe a signal if a relay is nearby) thrown into the mix?
 
I think I recall that there may be a facility or two somewhere that has a room where all the air is sucked out in order to replicate the vacuum of space. I take it the cell phone, if placed in there, would experience a similar situation, but with gravity (and maybe a signal if a relay is nearby) thrown into the mix?

In principle, yes. But a vacuum chamber with a smartphone inside is unlikely to ever reach pressures like that in outer space. Making a good vacuum is tough, even when you carefully consider what materials you put inside. Put something in it that has not been designed as vacuum compatible (like. a smartphone) and it becomes next to impossible.
 
It would depend on whether there are any pressurised components that are not designed to withstand a vacuum. The batteries might fail in a vacuum, as may the accelerometers. Not convinced that they would, but they might.

It also depends on the temperature. Some components wouldn't work in the really cold temperatures of space. For example, people over-clocking with LN2 need to be careful not to get some chips too cold, or they simply won't work (eg. there was an issue with early revisions of Sandy Bridge chips that had a 'cold bug' that stopped them working as temperature < ~ -15°C). I think now they're Ok down to ~ -60°C.) I do wonder whether batteries would work, as low temperatures may cause a phase change in the electrolyte, or even change the properties of the anode / cathode.
 
The cold is not an issue at all. Although space is cold, the vacuum there has a very low density, so there virtually no heat transfer by convection. So the only way for the phone to cool done would be black body radiation. But at operating temperatures of a phone, black body radiation is quite small and probably much less than the heat generated by the phone itself. So overheating would be a much bigger problem than the cold.
 
New question.

If you recall, I posted a question about whether the current global warming crisis may end up turning Earth into the next Venus. The answer to that indicated it wouldn't.

Under current accepted warming scenarios, what might the new equilibrium world temperature be? At that new equilibrium, how much permanent ice might remain when the melting pretty much stops?

With that in mind, compared to that new equilibrium temperature, how much hotter(?) might it need to be in order to melt ALL* ice on Greenland and Antarctica?

* EXCLUDING mountaintop ice. I'm sure the mountain ices in most parts of the world would be goners at such high equilibriums, but considering the locations of Greenland and Antarctica, at least some mountaintop ice may remain, once rebounding is complete. I am unsure whether the even-higher equilibriums needed to melt even that ice would trigger the runaway greenhouse needed to make a new Venus.
 
I don't know that there would be any form of an equilibrium. How much heating takes place will depend on ongoing human activity. It has no independent definition outside of human activity. And so the variables aren't really known at this point. At what point does it get so warm that people's behavior changes? No one can answer that. We can predict, based on current trends, but what if those trends are subject to change? And, eventually human activity will change, and the atmosphere will begin to cool again. When? No way to know at this point.
 
Is there any way to even take a stab at calculating which single species has the greatest total biomass? Like, I know that ants probably have a worldwide biomass several orders of magnitude higher than humans, but there are probably thousands of species of ants.
 
Well, my hunch would be something like cyanobacteria, and it's hard to classify bacteria as a species. Species is less defined than you'd think.

So eschewing that, I'd guess a tree. I highly doubt it'd be an animal. Keep in mind food chains here... plants should out number animals in terms of biomass by an order of magnitude.
 
Yeah . . . I sort of had all those caveats in mind, but I am not sure how plant species diversity compares to animal species diversity.

Just speculating based on my travels, but there's not a large diversity of trees when you reach the taiga. It's just an endless swath of white spruce trees from Labrador to Alaska. Siberia is similar, with pine. It goes on and on and on like grassland steppes, except trees have a lot of biomass in them.
 
Just speculating based on my travels, but there's not a large diversity of trees when you reach the taiga. It's just an endless swath of white spruce trees from Labrador to Alaska. Siberia is similar, with pine. It goes on and on and on like grassland steppes, except trees have a lot of biomass in them.

Must it be living biomass? Because trees have a lot of dead biomass in the form of the dead Xylem in their wood.

Also, it gets a bit grey when you consider the human body is comprised of a lot of bacteria also. There is a commonly cited statistic about 90% of the body being bacteria, but that's probably by number, rather than mass.
 
Must it be living biomass? Because trees have a lot of dead biomass in the form of the dead Xylem in their wood.

Also, it gets a bit grey when you consider the human body is comprised of a lot of bacteria also. There is a commonly cited statistic about 90% of the body being bacteria, but that's probably by number, rather than mass.

I think you'd only ignore rot. After all, a dead xylem cell is still an integral part of the organism.

The human body number would have to be a number percent, not a mass percent.
 
Is there any way to even take a stab at calculating which single species has the greatest total biomass? Like, I know that ants probably have a worldwide biomass several orders of magnitude higher than humans, but there are probably thousands of species of ants.

Pretty improbable to do more than very rough estimate.
You'd have to mass all elements on Earth and then be able to tell the inorganic from the organic, and then you'd have to guess how much of the organic forms was actually in a species. It's easy to see how problematic it in considering organic waste molecules----are they part of biomass or are they already excreted into the environment. And then you'd need to actually measure the elemental composition, say by some spectral analysis that required minimal sample preparation.

It'd be easier to due random samples of different biomes, figure the dominant species in each biome multiplied by the biome's prevalence and call it a day. It's easily a microbe, and probably a bacteria, that is the most prevalent in each biome.

The top of list would probably be the most common topsoil bacteria, but then who knows about the oceans?


who would win in a fight T-Rex or Spinosaurus


Jesus, in the VelociRAPTURE!
 
Pretty improbable to do more than very rough estimate.
You'd have to mass all elements on Earth and then be able to tell the inorganic from the organic, and then you'd have to guess how much of the organic forms was actually in a species. It's easy to see how problematic it in considering organic waste molecules----are they part of biomass or are they already excreted into the environment. And then you'd need to actually measure the elemental composition, say by some spectral analysis that required minimal sample preparation.

It'd be easier to due random samples of different biomes, figure the dominant species in each biome multiplied by the biome's prevalence and call it a day. It's easily a microbe, and probably a bacteria, that is the most prevalent in each biome.

The top of list would probably be the most common topsoil bacteria, but then who knows about the oceans?

Soil food webs are diverse, not really dominated by a single species of bacteria. While the total biomass of bacteria might be immense, a single species -- again, ignoring how hard it is to define species here -- is not going to be so.
 
I was listening to a "Scientific American 60-second science" podcast this morning, and it talked about looking for signs of light on exoplanets by trying to find reflected light from the planet among the starlight from the associated star. They mentioned that light reflected from the planet would be polarized. They are examining the light that the Earth reflects to the moon.

By what mechanism would light reflected from Earth be polarized? I would think that the light would be just as scattered as light emanating from the sun.

See, for example, http://www.space.com/14645-alien-planets-atmospheres-scattered-light.html.
 
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