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Comment Re:hostile ot all known life? (Score 1) 77

It should be noted that life almost certainly started in Earth's oceans (where the vast majority of it remains to this day -- life outside the oceans is practically a footnote). I do believe are hydrosphere is approximately two-thirds hydrogen, one-third oxygen (by atom count -- by mass, of course, the one oxygen atom outweighs the two hydrogen atoms).
Space

Astronomers Investigating Unknown Object That Hit the Earth In 773 AD 84

KentuckyFC writes "In November 2012, a group of Japanese scientists discovered that the concentration of carbon-14 in Japanese cedar trees suddenly rose between 774 AD and 775 AD. Others have since found similar evidence and narrowed the date to 773 AD. Astronomers think this stuff must have come from space so now the quest is on to find the extraterrestrial culprit. Carbon-14 is continually generated in the atmosphere by cosmic rays hitting nitrogen atoms. But because carbon-14 is radioactive, it naturally decays back into nitrogen with a half-life of about 5700 years. This constant process of production and decay leaves the amount of carbon-14 in the atmosphere relatively constant at about one part in a trillion will be carbon-14. One possible reason for the increase is that the Sun belched a superflare our way, engulfing the planet in huge cloud of high energy protons. Recent calculations suggest this could happen once every 3000 years and so seems unlikely. Another possibility is a nearby supernova, which bathed the entire Solar System in additional cosmic rays. However, astronomers cannot see any likely candidates nearby and there are no historical observations of a supernova from that time. Yet another possibility is that a comet may have hit the Earth, dumping the extra carbon-14 in the atmosphere. But astronomers have ruled that out on the basis that a comet carrying enough carbon-14 must have been over 100 km in diameter and would surely have left other evidence such as an impact crater. So for the moment, astronomers are stumped."

Comment Re:Reporters have zero clue, News at 11 (Score 1) 230

Or perhaps the reports here have a bigger clue than you. Yes, jet fuel is kerosene, but not all kerosene is jet fuel. If they were, in fact, using jet fuel, using the more specific term would be more accurate. Do you have some reason for thinking they got their facts wrong here?

Jet fuel is liquid, too. They could have reported that they used liquid, which would be equally true... but even less specific and thus less informative. The more specific you can be, the better.

Comment Re:units (Score 3, Interesting) 67

Only that was what was said. They said they were the same size as a basketball court...

Actually, that's not what they said. They said that the probe would not have been able to power itself even with solar panels the size of a basketball court. It's a hypothetical statement. My car would not be able to lift itself, even if it was filled with hydrogen. This is true, but in saying this, I'm not saying my car is actually filled with hydrogen, just pointing out that it wouldn't have enough lift even if it was.

Granted the way they said it unfortunately implied what you said. But it's not what they actually said.

Comment Re:Need for materials (Score 1) 265

. (And then there's the environmental advantage of mining asteroids over terrestrial mining.)

What, pray tell, might the advantage be? I dare say that creating a rocket and fuel to launch tones of stuff far enough into space to reach an asteroid is going to be pretty rough on the local environment. Then add the ability to return at least some recovered mass and I'm thinking we are nowhere near an environmental wash for quite some time.

You are either overestimating the environmental impact of a rocket, or way, way, way underestimating the environmental impact of mining on Earth. Also, "far enough into space to reach an asteroid"? The fact that you thought this worth mentioning, rather than simply saying "launch tons of stuff into space", makes it sound like you mistakenly believe it takes a lot more effort to send something to an asteroid than it does to get it into orbit, which is pretty much the exact opposite of the case. Get to orbit, and you're nearly done. The amount of fuel you'll expend getting to an asteroid is just a few extra percent on top of what it took to get to orbit. In any case, you'd have a near impossible task to design a rocket that had as much environmental impact as a mine.

Comment Re: Side-effects (Score 1) 139

[Citation needed]

"Most mammals normally cease to produce lactase, becoming lactose intolerant, after weaning,[4] but some human populations have developed lactase persistence, in which lactase production continues into adulthood. It is estimated that 75% of adults worldwide show some decrease in lactase activity during adulthood.[5] The frequency of decreased lactase activity ranges from 5% in northern Europe through 71% for Sicily to more than 90% in some African and Asian countries.[6]"

70% would mean that 7 out of every 10 people I know would be lactose intolerant. However, that ratio for me is more like 1 in every 100.

So either I'm an extreme statistical outlier or you're spouting bullshit. Guess which one I'm betting it is?

Do not try to generalize from personal experience: you are not the center of the universe. (You are, in fact, a moron.) The human mutation that allows some adult humans to continue to tolerate lactose into adulthood, an extremely abnormal trait for mammals, is only common among those of northern European descent, becoming an increasing smaller minority the further afield you get from northern Europe or its colonies.

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I tell them to turn to the study of mathematics, for it is only there that they might escape the lusts of the flesh. -- Thomas Mann, "The Magic Mountain"

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