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from Tmtoulouse (Talk), group Site wide (urgent) at 15:23, 18 April 2014

Bronze-level articleLunar bukkake hypothesis

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Rescued from the

Global Flood

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Seven of the clean kind

The lunar bukkake hypothesis is a young-Earth creationist conjecture regarding the origin of craters on the moon. It has been proposed and repeated by YouTube creationist NephilimFree - although he didn't give it the derogatory name used here.[1]

Contents

How it works

One of the many problems with young-Earth creationism is that the Moon (among other bodies in the solar system) has a heavily cratered surface. The number of craters, given the known rate of meteor impacts across the solar system, is far too great for it to have all been freshly formed 6000 years ago. Barring Goddidit or other form of magic, this presents an issue for creationists.

According to NephilimFree, the water from Noah's global flood lay under the Earth's crust. During the flood, the crust dropped down and this forced all the water to shoot upwards. The water, travelling at hypersonic (supersonic according to Nephilimfree) speed from the force, would have splattered the moon (hence the name of the hypothesis) and caused all the craters to form. NephilimFree also expands this theory to explain the existence of comets.

Minor scientific problems

Conservation of energy

The energy released by the crust dropping can be easily measured. We discount the inner 9 km of rock as they essentially haven't moved, simplifying the calculation a little.[2]

Primarily it is an issue of conservation of energy. This is simple to illustrate. Consider a 10 km thick section of rock; its width and breadth don't matter much, but make it a 1km by 1km slice for the sake of unit numbers. If this drops straight down into a 1 km deep underwater ocean, the amount of energy created is the equivalent of just a 1 km section dropping 10 km down (see diagram). Given a perfect system where energy cannot be lost (to friction, for example), this is enough energy to send another lump of rock 10 km up. The density of water is about a quarter or so of the Earth's crust so it can go a little higher, about 40 km up. Not exactly enough to get to the moon, which is nearly 10,000 times further away.[3]

Adding in friction, such as resistance of rock and air, the height that the water can reach as a result of these hydroplates dropping becomes much smaller. This is difficult to quantise precisely, but it certainly won't improve things for this creationist nonsense. So by the same principle that means the fat kid is the ruler of the see-saw, we can demonstrate the concept is fundamentally flawed before getting into the details of these creationist insights.

The target size

The moon is a relatively small target, about 30 arc minutes across in the sky.[4] Therefore the odds of hitting it with any of the ice meteors produced by NephilimFree's method is very low, unless the amount of water released in this manner was much, much, much greater than even NephilimFree claims. Assuming a reasonably even distribution of water flying up into space, we can calculate how much would eventually hit the moon. The surface of a sphere is calculated from a well-known classroom equation:

\!A = 4\pi r^2

So the Earth's surface therefore works out to 500,000,000 km2 thanks to a mean radius of just over 6,000 km. Assuming 1 km of water under the crust we have, simply,[5] 500,000,000 (5 x 108) km3 of water. But how thinly spread would this water be once it's been fired half a million kilometres to the moon? A sphere that would stretch to the moon would have a surface of approximately 2,000,000,000,000 (2 x 1012) km2 - 4000 times larger than the Earth by surface area. Thus dividing our 1 km depth of water we find that there would be only 25 centimetres depth of water that would statistically hit the moon. Hardly the grand splattering required to generate the 300,000 or so craters on the moon's surface.[6]

The theory also hardly explains the even more cratered surface of the far side of the moon or the craters on every other body that has been examined in the solar system.

Nozzle velocity

NephilmFree has defended his claim with the idea that the "nozzle size" matters. That is, when you try to squeeze water through a smaller space, it speeds up. This is true, but only in a system where pressure can build up behind the bottle neck (Neph is misapplying Bernoulli's principle). This is the case with a tap or hose pipe where water is constantly being pushed through the system, building up pressure and force which manifests as the greater distance that the water can travel. In situations where the pressure cannot build up and has only a constant amount of force to use (such as a barrel that is draining water through a hole in the side) the nozzle sizes does not affect the velocity of the water and the distance it can travel.

The water would have to reach Earth's escape velocity (at least) in order to hit the moon. It's a common misconception that this is the speed you have to achieve to "break free" of the Earth's gravitational pull - it's just the speed you have to be travelling when you cut your engines off and stop applying additional force. This value actually decreases with altitude; thus providing you constantly push yourself upwards with consistently applied force you could break free of the Earth's pull at any speed. This is why rockets or even a space elevator can leave the Earth's orbit at a lower speed - they're constantly applying force with their motors and engines. However, in the case of water shooting up from the Earth's surface, the "misconception" is actually fairly good representation as the water cannot gain more momentum from motors or engines. In this theory it has only one chance to receive energy in the form of momentum so it would have to be accelerated to the surface escape velocity. The water would have to be shooting up from Earth's surface at 11.2 km/s (40,320 km/h) in order to escape the Earth's gravity and make its way towards the moon. The accelerating force required to do this is far, far above what you could get[7] from even dropping ten cubic kilometres of rock onto some water, regardless of NephilimFree's erroneous claims about nozzle velocity (which is what the above discussion about conservation of momentum confirms).

Comet composition

Halley's comet. Its corona is near 20% carbon monoxide and so if this ice originated on the Earth 6000 years ago, the conditions would have been inhospitable to life.[8]

An additional claim is that the ejected water then goes on to explain the existence of comets in the Solar System - although certainly not their highly elliptical and far-reaching orbits. This can be demonstrated to be bullshit by actually looking at the composition of comet ice, which has been measured with spectroscopic methods by various spacecraft.[9] As a result of this, we know that comets can be around 0.1% hydrogen cyanide (HCN) anywhere up to 15-20% carbon monoxide (CO). In the case of the HCN, this doesn't seem like much but would make drinking about 1 litre of water (assuming Noah's flood waters had the same composition as comets) to be lethal. In order for the CO to be present in such high concentrations, the water would have to have been on Earth under a partial pressure of CO. As it stands, CO dissolves poorly in water and a significantly high pressure would be needed to force the gas to dissolve. Working backwards from the comet concentration we can determine that the atmosphere during Noah's great flood would be about 0.01 atmospheres of CO. Like the cyanide, this concentration is above the lethal dose - which is around 1% CO to kill within minutes.[10] In short, if this was the case surviving the flood would have required far more than a sturdy boat - God's orders to Noah should therefore have involved instructions to build space-age life support systems!

Temperature

Using Geothermal gradient one can estimate the lower bound of temperature/heat content of fluid hidden deep below the surface. using the Gradient of 22.1°C per km of depth (avg by location) at 10km deep the water at the deep would be at least 200°C hotter than the water at the surface[11]. Therefore, either we were shooting out superheated steam instead of liquid water (Remember that at the nozzle the pressure is atmospheric), or the earth was pretty much frozen over at temperatures of lower than -100°C.

In the case of ejecting steam, for the amount of water at 4.5 billion cubic kilometres (see the approximated calculations here) counting the existing oceans(1.3 billion cubic kilometres) (because it would have vapourize the entire existing ocean even at 0°C average) it should have 3.2 x 1023 moles of water, which using ideal gas law as an approximation, at a minimum of 100°C[12] and atmospheric pressure, gives 9.8 x 1021 cubic meters of steam (lower bound), which would cover the earth all the way to a height of 7300 kilometers (lower bound)[13], so everything alive would have been steam cooked in a matter of minutes, furthering the need for space-age life support systems.

Fossils on the moon

Bearing some similarity to known conspiracy theories and far-out ideas about history,[14] NephilmFree has also suggested that lunar bukkake theory would result in us finding fossilized remains on the moon. This would be quite consistent with huge quantities of water splashing up and hitting the moon, although not entirely consistent with water travelling at the 11.2 km/s escape velocity for it to leave the Earth's surface, which would have shredded any remains pretty quick - by comparison, water jet cutters can cut through steel at a fraction of this speed.

See also

Footnotes

  1. If you don't get it already, you're probably not the sort that wants to know, so don't bother looking it up.
  2. You can satisfy yourself that this hand-waving simplification works by imagining a point mass of 10 cubic km of rock dropping only 1 km (thus the force is proportional to 10 x 1) compared to just 1 cubic km of rock dropping 10 km (thus the force is proportional to 1 x 10).
  3. Why do people laugh at creationists? (part 33)
  4. "I used to bullseye womp rats in my T-16 back home. They're not much bigger than 30 arc minutes!
  5. This is a simplification. We'd have to integrate the volume between a sphere of 6000 km and 6001 km to get a real value. The size of the spheres in question make the difference negligible and less than the margin of error thanks to the fact the Earth isn't a perfect sphere anyway.
  6. ESA - Moon facts
  7. doing the math would get you no more than say 650 m/s (velocity increase is proportional to the square root of pressure increase so it will never be much), slightly less than Mach 2 but still not enough to reach 10% of the surface escape velocity.
  8. Woods, T. N.; Feldman, P. D.; Dymond, K. F.; Sahnow, D. J.; Rocket ultraviolet spectroscopy of comet Halley and abundance of carbon monoxide and carbon. Nature, 324, 436-438 (1986)
  9. NASA.gov - Comets
  10. Why Do People Laugh At Creationists? (Part 34)
  11. Checking the phase diagram validates that it is still in liquid form (~300 MPa, 500K).
  12. This is a lower bound due to mass of steam being ~3 times as much as the mass of existing oceans.
  13. Suprisingly, it's also ~7300 km (lower bound) if you don't assume the system to be well-mixed, as in no heat exchange occured between the steam and the oceans.
  14. Overcoming Bias - Dinos on the Moon
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