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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift

KentuckyFC writes "Many types of small spider release threads into the air which then lift and carry them significant distances. Biologists have found them at altitudes of up to 4 km. The conventional thinking is that the threads catch thermal air currents which then carry them away but this does not explain how spiders perform their trick even when there is little or no wind. Now one physicist says the explanation is the atmosphere's natural electric field which has an average downward-pointing magnitude of 120 Volts per metre. He calculates that a strand of silk need only gain a negative charge of around 30 nanoCoulombs to lift a spider. That explains how the spiders take off on windless days, how they reach such great heights and how several strands can lift heavier spiders of up to 100 milligrams."

13 of 213 comments (clear)

  1. Next step is testing by schneidafunk · · Score: 5, Insightful

    "Of course, Gorham’s ideas will need to be tested by actually measuring the charge on gossamer spider silk as it is generated. That’s an experiment for an enterprising biologist to take on."

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    Some people die at 25 and aren't buried until 75. -Benjamin Franklin
  2. Re:Yes, But... by deusmetallum · · Score: 4, Informative

    He lives in New York, he's always swung from the multitude of high rises.

  3. Re:Yes, But... by MightyYar · · Score: 5, Funny

    It's a shame that they ruin it with that - the rest of the story is totally plausible.

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    W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  4. Yes by Flipstylee · · Score: 4, Insightful

    Stories like this are the reason i frequent /.

  5. Airborne mini drones, here we come.... by gestalt_n_pepper · · Score: 5, Funny

    This really bugs me.

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    Please do not read this sig. Thank you.
  6. Nature is amazing by brunes69 · · Score: 4, Insightful

    To me stuff like this is what proves evolution. There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

    1. Re:Nature is amazing by jones_supa · · Score: 4, Insightful

      I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.

    2. Re:Nature is amazing by MadKeithV · · Score: 5, Insightful

      I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.

      Most "precisely engineered" stuff that's actually engineered is still the product of large quantities of trial and error, at some level :)

    3. Re:Nature is amazing by hort_wort · · Score: 5, Insightful

      What if the intelligent designer just wanted to use evolution? I've never understood why the two solutions have to be exclusive.

    4. Re:Nature is amazing by RKThoadan · · Score: 5, Insightful

      "not as efficient?" These seem a whole lot more efficient than wings to me. A single one-time expenditure of energy and they go for miles. There are downsides to this method of course, most obviously that they don't have any control of where they go. But if you accept that limitation this seems to be a nearly optimal method of flight.

  7. Re:batman by MickyTheIdiot · · Score: 5, Informative

    The bat signal itself doesn't fit with physics.

    My parents have owned a searchlight rental business for 30 years now. For the first Batman movie they were asked to put a bat signal cutout on the searchlight to simulate the bat signal. The thing is that searchlights have too high a candlepower and the light just bends around the cutout. The light spreads more the farther away from the searchlight. It looks cool when shown against a wall, but far out in the sky it simply doesn't work. The physics of light doesn't allow it.

  8. Re:Yes, But... by meerling · · Score: 4, Funny

    You're trying to work out continuity issues from an old and poorly made no budget ancient cartoon?
    You might as well complain that dropping an anvil on sombody's head will not result in a bump but will crush their freaking skull and kill them.
    Besides, Spiderman doesn't do web flight. He must not have been bit by a gossamer spider. :)

  9. Re:120V/m - why can't we tap that by jones_supa · · Score: 4, Informative

    I've just read that one bolt of lightning powers one household with all their energy needs for a month. I'm not too sure how accurate that is; but I think we'll need a lot more than that.

    I will try to plug the numbers in. Let's see how this goes.

    According to the physics.org toast power article, a lightning packs "over five billion joules of energy". I will round that down to 5 billion. A watt is the same thing as "joules per second". A month has 60 * 60 * 24 * 30 = 2,592,000 seconds. Then, 5 * 10^9 J / 2,592,000 s = 1929 J/s. This means that we can run the house at a constant power consumption of 1929 watts. Converted to a standard kWh number that would be 1389kWh per month.

    That's pretty much on the spot. It would indeed be enough to run a house of a small family for one month, accounting electrical heating running around winter.