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Comment Re:My curiosity (Score 1) 22

No. Acceleration is change in velocity. That's what it is measuring. If velocity is not changing, acceleration = 0.

No experiment can distinguish between gravity and uniform acceleration, so if acceleration is what it's measuring, it can't possibly tell the difference between 9.8m/s^2 of acceleration and Earth-normal gravity. Indeed, just as Special Relatively is based on the fact that rest and uniform motion are the same thing, General Relativity is based on the fact that gravity and acceleration are the same thing. If you are sitting still on Earth's surface, you are undergoing 9.8m/s^2 of gravitational acceleration. In order for the accelerometer to read zero, you would have to be in free-fall.

Comment Re:My curiosity (Score 1) 22

An accelerometer doesn't measure speed but acceleration, if it was moving on earth at a perfectly constant pace (and perfectly smoothly) the accelerometer would likewise not measure anything, right?

If it measures acceleration, then whether at rest or undergoing smooth, constant motion, it should measure an acceleration of 9.8m/s straight down.

Comment Re:Lack of privacy knowledge (Score 2) 182

Understanding of basic vocabulary seems to have gone out the window today.

anonymous: without a name attached to the work/deed/etc. cf. greek/latin "an-" (without) prefix and "onym" (name)

pseudonymous: with a false name attached. cf. greek/latin "pseudo-" (false)

What's being described here is not pseudonymous, unless a note is being attached to each transaction saying "This transaction was made by Mark Twain" (assuming the actual person conducting the transaction isn't actually named Mark Twain).

Comment Re:Lack of privacy knowledge (Score 2) 182

By that absurd definition, anonymous posts aren't anonymous because they are posted, anonymous letters aren't anonymous because they're printed, etc. You fundamentally fail at understanding what "anonymous" means if you think being logged makes it not anonymous. What makes anonymous things anonymous is not the fact that they're not recorded, because indeed they all are, and have been for the thousands of years of anonymous writing/deeds/etc. What unites all the things we've described as "anonymous" for millennia is that what isn't recorded alongside the various things that are is the author's name.

Comment Re:There may well be life on Europa (Score 1) 216

Another mission to a world we've been to before will yield more interesting science that one to a world we've never been to before? That seems unlikely. Not saying there isn't a heck of a lot more to learn on Titan, but your reasoning here is bizarre.

The fact of the matter is, we don't know what we'll find if we go looking at Europa. One of the things about science is, instead of trying to find the answers to questions like that by just thinking about it (i.e. the philosophical method), the scientific method involves actually looking instead of merely guessing. If we want to know what we'll find on Europa, we'll have to send a probe and actually see.

You could fill a book full of perfectly reasonable statements about what we'd find on planets before we sent probes to them, all as reasonable as what you've saying, based on what we thought we knew at the time, and all dead wrong.

A mission to Europa is far more likely to yield scientifically interesting results than another mission to anywhere we've been before.

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.

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