pavelcherepan

Even starting from the Earth we generally use two- or three-staged designs, which is simply due to the fact that it's very inefficient to carry around empty fuel/oxidizer tanks and would be even more inefficient on a planet with higher gravity and denser atmosphere.

Who are 'we' or is it a quote? the Earth and Venus are called 'sister planets' mostly for the size, mass and overall composition. Their histories are very different based on what science knows, but there's no need to involve Venus in the first place, because we're talking about the Earth and as far as I'm concerned, Ophiolite had given you a great summary of the current knowledge of the formation of the Earth and its age. What do you not understand from what he wrote? I would also like to note that aligning your text to the right makes it really hard to read and that's probably why no one else uses it. Looking at your post I constantly get a feeling that I have my laptop upside down. David, it appears to me that you didn't read or didn't understand what your opponents have said before and now without any understanding of their arguments you keep throwing in some random numbers into your random calculations. How is this going to help your point? Do you have or do you not have evidence to support your idea that the Earth is older?

Could it be logic? I mean, every science is based on some sort of logical conclusions, on ability to find connections between a cause and effect, which is then written in mathematical form.

I don't think that it's really a conflict, rather an uneventful, slow-going and probably pointless debate, because it really depends on what definition of "science" you use, for example: Wikipedia: Since mathematical predictions are untestable without involving natural sciences, it's not a science. Encyclopaedia Britannica: http://www.britannica.com/EBchecked/topic/528756/science Mathematics by itself is not concerned with physical world and involves no experimentation, hence not a science. But (same source): In this sense it's a science. From Google thesaurus (3rd definition): So in a broad sense mathematics is indeed a science, since it collects and organizes knowledge on a particular subject, yet it has very little to do with scientific method and is not a science in a sense that most other sciences are. I'm not sure if this debate can ever be resolved without some drastic change.

Not a 'natural science', yes. The question whether it's a science or not is being debated: With your other question: I'll paraphrase. Physics studies any natural phenomena that can be observed with any senses that humans have at their disposal. Note: even if a phenomenon can't be observed naturally with normal senses (e.g. X-Ray) technology is used to convert the input into something perceivable by a human being. How does that sound?

Physics studies objective reality, while mathematics focuses on abstract problems that may or may not be relevant to the real life. For example, if in physics (or any natural science) theory must be supported by experimental data, in mathematics it only has to be logical and consistent, no experiment is required. A lot of people, including Feynman in the link I attached above, describe mathematics as a 'language' of science, which in my mind is a good analogy. And since it's a language, nowadays pretty much any science uses maths to some extent. Also, it's unclear which one, physics or maths, takes priority, because if in old times mathematics advanced more or less on its own, but since probably 17th century most of the major advances in maths are due to the need to mathematically explain more and more complicated physical phenomena.

That is because here I incorrectly read those to be GWh, not GW. So increase in power of 422 GW will result in an increase in energy production per year of ~3700 TWh. Which, using the number I used before (1029 kg CO2/MWh) gets us to 3.8*10^12 kg of CO2 per year or 10*10^9 kg CO2 per day. And that equates to 7.5*10^6 tonnes of O2 consumed per day. Your original estimate was very close, mine was wrong.

434238000 kg = 434*10^9 g/44g/mol = 9*10^9 mol CO2 , hence 324*10^6 kg O2 required per year, which is 0.9*10^6 kg or 900 tonnes per day.

If we assume this extra power comes from coal thermal plants and based on this: This power increase will equate to 422000*1029 = 434238000 kg of extra CO2 released. The number will be half as big if energy would come comes from natural gas plants.

Richard Feynman in his lectures sure seems to think so

There is another way to calculate it and it gives an even scarier number. Here based on observations they give an average number of O2/N2 ratio decrease at ~19 per meg per year. The current ratio in the atm is (21/78*1000000) = 269231 per meg. Assuming that nitrogen doesn't come from anywhere in massive amounts and all O2 lost will be incorporated in CO2 and other oxides than we're looking at a target level of ~140000 per meg and with 19 per meg/year reduction it gives us 7368 years and now this is a very scary number.

But that 1 million molecules of oxygen represents the current concentration in the atmosphere of 21%. Then in order to get to 11% of atmospheric concentration is 1,000,000 - ((11%/21%)*1,000,000) = 476190 O2 molecules needs to be lost per 1 million.

That's odd. It worked for me yesterday and now it doesn't.

A precursor to modern-day physics was "Natural philosophy" (it was called that at the time of Newton, for example) implying that it studies everything the nature has to offer, so in my mind generally Physics would be the one you need.

StringJunky, I got different value from what you calculated. The way I understood what they said we lose 19 per 1,000,000 molecules of oxygen and so getting to 11% oxygen concentration requires losing almost half ~476190 molecules, which makes it ~25063 years. Or did I go wrong somewhere?

What core temperature are you referring to? Modern day? This paper, for example, suggests it would be possible to return to partially crystalline state in just 30 my (plus or minus 10). http://www.nature.com/nature/journal/v437/n7063/full/nature04129.html The next study with highly technical calculations suggests a cooling time of ~100 my (that including the 'precipitation' of evaporated silicate rocks). https://books.google.com.au/books? hl=en&lr=&id=8i44zjcKm4EC&oi=fnd&pg=PA179&dq=%22giant+impact%22+%26+%22cooling%22&ots=7J7G5oM4kO&sig=wwNA70Ueg5akNq0HCdlX_wD6fPU#v=onepage&q=%22giant%20impact%22%20%26%20%22cooling%22&f=false And here you also have some studies on thermal equilibrium, molten surface and what effect water had on all of it. http://www.jstor.org/discover/10.2307/74159?sid=21106221504453&uid=3737536&uid=4&uid=2 http://www.sciencedirect.com/science/article/pii/S0012821X99001569 http://adsabs.harvard.edu/abs/2000orem.book..413A

There's some research if you look hard enough. Here's the oxygen concentrations measured at Cape Grim for the last couple decades (btw, who knows what is the unit 'per meg'?) Here's the general oxygen levels trend for the last billion years: And the reason why not much research has been done on recent anthropogenic effects is probably hidden in this quote:

It is actually very possible that the Earth was cool enough to have water and oceans about 100-150 million years after formation, which is based on studies of oldest known zircon crystals: http://geoscience.wisc.edu/geoscience/people/faculty/john-valley/a-cool-early-earth/ Prior to that the Earth might have been partially or completely molten due to the Giant Impact that formed the Moon and in general impacts with smaller bodies during initial coalescence stage. Also the Iron Catastrophe at a later time could've lead to formation of magma ocean. http://astro.hopkinsschools.org/course_documents/earth_moon/earth/geologic_time/iron_catastrophe.htm http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1988LPICo.681...20G&db_key=AST&page_ind=0&data_type=GIF&type=SCREEN_VIEW&classic=YES In any case the oldest known rocks are some 4 bya and oldest evidence of life in the form of stromatolites is some 3.5 bya. http://www.nature.com/nature/journal/v441/n7094/full/nature04764.html

Then maybe "Gott ist tot" so to speak?

Acme, thanks for the links. I'll have a look at that.

Yes, I do that sometimes, agreed. Can't help it. But in this case I wasn't nit-picking. The actual question was: 1. Article you referred to suggested that in case of Venus it's due to the fact that it stayed molten for longer time and lost all the water. 2. Based on what I read before, I said that there were other secondary sources that could've provided water for oceans. 3. Hence the absence of oceans on Venus is due to an extreme greenhouse effect and closeness to the Sun and not because it lost surface water. How is that not contributing to discussion? Did I try to answer the OP's question 'Why is that so?' or did I not?

NASA site has some explanations to that regard: http://neo.jpl.nasa.gov/news/fireball_130301.html As far as disintegration is concerned, same NASA website and the article I linked earlier (from page 819) have some descriptions of what causes it and how it happens. P.S. It's not a comet but is usually referred to as meteor or 'superbolide meteor'. On a side note - Ain't it strange by the way? Pieces of it did land on the surface, so why meteor? Why not meteorite?

OK. In the article you attached they mention the time for the surface of the Venus' surface to solidify at about ~100 my. So that puts it somewhere 4.4-4.3 Gya. So let's consider as they mentioned in the article the total water inventory goes down to 0.1 MEO or similar. Then what about Late Heavy Bombardment that happened 4.1-3.8 Gya? There was plenty of water brought about by all these objects. So that will increase the total water inventory to some degree, and more importantly, it will be the inventory on the surface, rather than buried in the mantle. Secondly, what about volcanism? Venus is volcanically active and all the effects mentioned in the paper do not mention any major changes to the water inventory in the mantle. So, for the example of the Earth in volcanic gases we have between 30 to 92% of H2O vapor. The former is for diverging plates, the latter - for converging. We can safely disregard converging plates example as there is a lot of water trapped within subducting slab and use the smallest value of 30% of vapor in volcanic gas. Still with the amount of volcanism and the timeframes involved had it not been for the tremendous greenhouse effect and being so close to the Sun, Venus did have some secondary sources of water. There have been a few examples discovered in Greenland, I think with formations looking similar to BIFs with >3.7 Gy age. But those are only a few localised patches and their formation is still being discussed. All other BIFs come to be between some 2.4 and 2 Gya

UPDATE: Sorry, cross-posted with Acme with similar info. There is relatively a small amount of water in the inner Solar system and that relates to how SS was formed. When the Sun had finally started fusion the solar wind started dragging all the lighter elements towards edges of the system. For example, we have Ganymede (Jupiter's moon) that is thought to have an underground ocean holding more water than there is on the Earth. The inner planets did have some water as they formed but with the lack of atmosphere and magnetic field H2O was easily broken down by solar radiation and then both hydrogen and oxygen escaped. What we have now has partly been brought about by comets and asteroids or by volcanism and releasing water from the mantle. Here I found calculation for what would temperatures on Venus would be had it not been for the greenhouse effect, which suggests that water could exist in a liquid form. Although, I see that the guy uses the modern-day albedo of the Venus (which is mostly due to atmosphere) in his calculations and so I've used his formula with an albedo similar to that of Mars and got 456 K, which is definitely too much.

OK, now I see. So you have a frictionless surface suspended on springs. You're initial drawing didn't have this one. Did you change your design? So now it makes sense - you'll just need a frictionless material, probably brought from the other universe or simply not consisting of atoms or molecules and you're golden. Best of luck with that!