pavelcherepan

Only temporarily. If the region's ecosystem is supportive of tree growth, they will grow back again. Grasslands on the other hand is a specific ecosystem where trees are rare due to low amounts of precipitation and also infertility of local soils.

I'd actually want to correct my earlier post. In fact the barycenter of this hypothetical system won't be at the center of the star. That would be the case if orbit was perfectly circular but since they are somewhat elliptical barycenter will shift towards one of the planets when it's in the pericenter and away from the planet at the apocenter and then slowly drift towards the center of the star (autumn and spring equinoxes) and then move to the other side.

Are there only two planetary bodies in the system you're describing? If that's so and if their masses are equal then the barycenter would be at the center of the star, so that the star would be stationary in the reference frame centered at barycenter. If there are other bodies present then all of them (and the star too) will be orbiting the common barycenter which will be located well inside the star but not at the exact center.

Here's a quote from the second link: Also from the first link: And as far as Murphy's law is concerned, if there's a chance that a well could be constructed poorly it will happen:

Have a look at these: http://ec.europa.eu/environment/integration/energy/pdf/fracking%20study.pdf https://www.gov.uk/government/publications/shale-gas-extraction-review-of-the-potential-public-health-impacts-of-exposures-to-chemical-and-radioactive-pollutants And also:

Mostly that would be contamination of ground waters, but also there is are some studies that link increased seismic activity with fracking. There are also some noise and air pollution concerns but I'm more worried about the first two.

Apparently there's been an oil field found in Sussex in the vicinity of Gatwick airport. With some 100 bn barrels it's supposed to be one of the biggest onshore deposits in the world and while only 3-15% can be extracted it's still a lot of oil. Oh, yeah, and fracking will be required. Now I wonder whether common sense and community pressure will be able to hold off the development of deposit? EDIT: Sorry, forgot to add a link http://www.theguardian.com/business/2015/apr/09/west-sussex-oilfield-could-produce-50-to-100m-barrels-of-oil

I think it's you who is being silly. If by easing off on sanctions the Western nations can in the future try and rely on the pro-west younger generation and your way of doing things would simply destroy all of this. In the face of hardships, especially if those are brought about by external forces what does flourish? That's right, nationalism. Do you really want to turn educated pro-west people in Iran into nationalists who will also march on streets screaming "Death to America!"? Sanctions won't stop Iran from getting the bomb, bombing is unlikely to stop Iran from getting the bomb and the current deal is the best option out there. If you have a better one, as iNow said, we'd love to hear it.

Yeah. What's wrong with indisputable evidence?

1. Indisputable evidence

Brontosaurus was a sauropod dinosaur species originally identified in 1879 and was some 20 meters long, weighted 15 tonnes and was a nice and friendly herbivore. Later on in 1903 after more rigorous research it was decided that brontosaurus was the same as already known Apatosaurus and then the genus name was abandoned. Now, after even more research paleontologists have again changed their minds and decided that brontosaurus is in fact a different scecies and was different from apatosaurus in term of neck structure. Good to hear this but I wonder if that will last http://www.scientificamerican.com/article/the-brontosaurus-is-back1/ http://www.theguardian.com/science/2015/apr/07/brontosaurus-is-back-new-analysis-suggests-genus-might-be-resurrected

Thanks! Mostly going to St.Petersburg, but will try to get to Ukraine if possible, I have some relatives near Kiev as well

Wow! Thanks a lot imatfaal! A lot of good info!

Flour costs money and kaolinite can be dug for free on a river bank Yeah, silicosis would be a problem if you do it too often, but once a year shouldn't be too bad.

Cocaine Kaolinite - white mineral that makes up big percentage of most clays and you often have almost pure kaolinite clays. When dry it's easy to get it into powder form and has no adverse health effects that I've heard of. And it's free too if you manage to find a proper sediment EDIT: Ouch. Apparently people also eat kaolinite, never heard of that before but here's the quote:

I guess it would be really hard to estimate because we don't know or can estimate the initial mass of Theia as it sets off towards Earth we don't know and can't really estimate the rate of accretion and without these it's just a guessing game.

The logic is impressive. That, given that one of the major US allies in the region - Saudi Arabia has capital punishment for homosexuality and severely disadvantaged position for women. Can;t really compare but from where I'm sitting human rights situation is better in Iran.

Hi everyone, thanks for reading! I have a 2-month old son and we're planning a trip to Russia in summer to visit some extended family members. Here in Victoria, Aus tuberculosis is all but nonexistent so much that our GP went into stupor for some 5 minutes when I tried to explain that we need to get a TB vaccination for our son. Now I have vaccination scheduled for the 2nd of June, but some of the things doctors told me are in conflict with what I read before, so I would greatly appreciate it if someone with knowledge in immunology could help answer those: 1) Our trip is scheduled for the end of July and with the immunization on 2nd of June is this enough time for developing immunity? 2) My son has another immunisation scheduled for 26th of May for DPT vaccine and Hep B. Could those be in conflict with TB vaccination? Doctors told me it's all good, but they didn't sound so sure. EDIT: Sorry, posted in a wrong forum. If any of moderators are reading this is it possible to move this thread to immunology forum? Thanks in advance.

I was thinking along the same lines with imatfaal, but I went with volume calculations. [latex]V_{roll}= \pi r_{outer}^2*h - \pi r_{inner}^2*h = 3.14*2.5^2*3-3.14*1.5^2*3 = 37.68[/latex] [latex]V_{sheets}=500*3*3*x = 4500x[/latex] [latex]x = \frac{37.68}{4500} = 0.008373 \,in[/latex]

[latex]v_e=\sqrt \frac{2GM}{r} = \sqrt \frac{2*6.67*10^{-11}*6*10^{24}}{1.5*10^{11}} = \sqrt {\frac{80.04*10^{13}}{1.5*10^{11}}}=\sqrt{53.36*10^2} = 73.05[/latex] My original calculation seems slightly off, still way lower than what you've got. Would it be because you never answer those?

Do you even read my posts? Or do you just start writing random stuff?

Yeah, I've figured that out already. Anyway, what's the physical basis for calculating impact velocity by subtracting escape velocities at two points? Show me a link or physical explanation of the calculation. Yes, I was saying that from the very beginning , but you never agreed and have been trying to prove it came from L3. And then suddenly you agree with me? By the way, your calculation for escape velocity at L4 is still off by an order of magnitude.

OK, so it wasn't you who said all that? OK? N one has even mentioned L3 until you started repeatedly bringing it up. You seem to have lost all your argumentation, you can't make a simple calculation without being off by orders of magnitude and you can't support your position with any relevant links or evidence. Now you're just making stuff up. Stop your straw manning. You said: Here are we not subtracting square roots of escape velocities at two different points? EDIT: OK, my fault. We're just subtracting escape velocities. Anyway, what's the basis for this calculation?

You asked about gravitational attraction, right? So for the Earth-size body and Mars-size body at 3*1011 meters away Fg will be 13.34*1015 Newtons. What other answer do you want? Also, I believe you've been explicitly told that his thread is only for the first question in the OP.

What do you mean? That's 300 million kilometers to L3 from the Earth. Your calculations are orders of magnitude off. 2. Explain physical reason for subtracting square roots of escape velocities at different distances? Can you show me where you got that formula from or explain what it's used for?