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troy

science vs religion

1,123 posts in this topic

As simple as that eh?

So build a massive ship in orbit... :)

Really, just think about it... what are Lagrange Points?

If there exists a neutral point, then how can the moons gravity have any effect on the water.... that alone should nullify the existing theory of tides.

The Lagrange points are basically equilibrium points in a dynamic system. Some of the them are unstable. They are not all neutral points where the gravitational force of Earth cancels the gravitational force of the Moon (although 1 definitely is), although the magntiude of the force exerted by the Moon and Earth are equal.

It makes sense to me that if gravitational force between two objects is directly proportional to the mass of both objects, and inversely proportional to the distance between them, then the effects of Moon's gravity would be neglible on a small object such as a rocket until it is in close proximity to the Moon, whereas a large fluid body such as the ocean would show more pronounced effects at the same distance simply because of the larger mass (and fluidity). The neutral point doesn't mean that the Moon can't exert a gravitational force past it - the neutral point is in relation to the net force on a third body. If the Moon didn't exert a gravitational force on the Earth (and vice versa), then it wouldn't even be in orbit, it would fly off. The gravitational force exerted on the ocean by the Earth is clearly more greater than that of the Moon's.

Edited by Galactic
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If the Moon didn't exert a gravitational force on the Earth (and vice versa), then it wouldn't even be in orbit, it would fly off.

I'll respond to the rest of your post soon, but just a quick one, let me throw something else into the works

What if the Moon is not orbiting the Earth? it is orbiting the Sun, but the Earth is in the way perhaps?

Now before ratdog has a go at me for having an opinion, I heard the above on the telly... very recently, so I'm just reporting it... but... ;) no no, I'll keep that to myself.... for now. :)

QIXL, series L 15: Long Lost

Stephen Fry says the Moon is not orbiting the Earth, it is orbiting the Sun.

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I'll respond to the rest of your post soon, but just a quick one, let me throw something else into the works

What if the Moon is not orbiting the Earth? it is orbiting the Sun, but the Earth is in the way perhaps?

Now before ratdog has a go at me for having an opinion, I heard the above on the telly... very recently, so I'm just reporting it... but... ;) no no, I'll keep that to myself.... for now. :)

QIXL, series L 15: Long Lost

Stephen Fry says the Moon is not orbiting the Earth, it is orbiting the Sun.

You're correct. I forgot the Moon is a special case. Since the gravitational force of the Sun on the Moon is more than twice that of the Earth on the Moon, the Earth and Moon together are considered a binary planet orbiting around the Sun, with the centre of gravity shifted from the centre of the Earth towards the Moon.

However, there still exists gravitational attraction between the Earth and Moon, a continuum which doesn't cease at the neutral point. Apparently it's the gravitational gradients (i.e. rate of change) which are important in tidal theory, which is why the Moon has more influence despite being weaker in magnitude of force. (Loving this discussion!)

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... :lookaround:

Interesting. I don't understand the bit where he says that reality is all 'fields of awareness'.

It's also pretty hard for me to escape my 'scientific stories', since what he is essentially saying is something I conceptualized from science, 'that conciousness is an emergent property of the brain'.

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I'll respond to the rest of your post soon, but just a quick one, let me throw something else into the works

What if the Moon is not orbiting the Earth? it is orbiting the Sun, but the Earth is in the way perhaps?

Now before ratdog has a go at me for having an opinion, I heard the above on the telly... very recently, so I'm just reporting it... but... ;) no no, I'll keep that to myself.... for now. :)

QIXL, series L 15: Long Lost

Stephen Fry says the Moon is not orbiting the Earth, it is orbiting the Sun.

An Astronomical body's Hill sphere is the region in which it dominates the attraction of satellites. To be retained by a planet, a moon must have an orbit that lies within the planet's Hill sphere. In more precise terms, the Hill sphere approximates the gravitational sphere of influence of a smaller body in the face of pertubations from a more massive body. (lifted from wiki)

The satellite or moon (mass μ) is orbiting the star (mass M) with the same angular velocity ω at the distance R+r as the planet (mass m) at the distance R (permanent full moon position).

The equilibrum condition for the planet is:

m a = F (Newton's second law of motion)

m ω2 R = G m M/R2

ω2 = GM/R3

The satellite is dragged by the combined gravitational forces exerted by the star and the planet:

μ ω2 (R+r) = G μ M/(R+r)2 + G μ m/r2

Inserting ω2:

G μ M (R+r)/R3 = G μ M/(R+r)2 + G μ m/r2

M (R+r)/R3 = M/(R+r)2 + m/r2

M (R+r)3 r2 = M R3 r2 + m R3(R+r)2

m R3(R+r)2 = M r2 (R3+3R2r+3Rr2+r3) - M R3 r2

m R3(R+r)2 = M r3 (3R2+3Rr+r2)

For r<<R: (R+r)2≈ R2, and 3Rr+r2 ≈ 0. The equation simplifies:

m R5 = 3 M r3 R2

m R3 = 3 M r3

r = R [m/(3M)]1/3

Mass of Sun:- 1.99x10^30 kg

Mass of Earth:- 5.97x10^24 kg

Orbit Radius:- 149,600,000 km

Hill's sphere:- 1,496,000 km

Orbit of Moon:- 384,400 km = 1/4 Hill Sphere

http://www.jgiesen.de/astro/stars/roche.htm (actually has a rogue G in the mathematical steps which I corrected).

I guess you could say the Moon is still in orbit so long as it stays within the Hill's sphere of the Earth. Interesting stuff.

Edited by Galactic
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@@Galactic I was doing OK until I got ambushed by all those hieroglyphics :shock:

Fair play - that looks disturbingly complex!

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Now before ratdog has a go at me for having an opinion, I heard the above on the telly... very recently, so I'm just reporting it... but... ;) no no, I'll keep that to myself.... for now. :)

Regurgitating stuff from the bbc is not having an opinion lol

Stephen Fry says the Moon is not orbiting the Earth, it is orbiting the Sun.

ah, well, why didn`t you say it was him, Didn`t know he was an astrophysicist though

technically, everything in the solar system orbits the sun if you want to look at it in a certain way

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@@Galactic I was doing OK until I got ambushed by all those hieroglyphics :shock:

Fair play - that looks disturbingly complex!

It gets much worse. Hieroglyphics might be an apt description as this is the simple Newtonian mechanics of centuries ago which has supposedly been long superseeded by Einstein's General Relativty (he published it in 1915, so it's exactly 100 years old this year!). The mathematics above is pretty basic algebra with simple substitutions. There's not even any calculus involved, so it might be suitable for GCSE/early A-Level standard.

In simple terms, (I believe) the mathematics starts by stating the equilibrium condition (Force = mass x acceleration) for the satellite that needs to hold at the extremities if it is to stay in orbit around the planet when both are effected by the star's gravitation. Then it's basically a case of "playing around" with the equation (by substituting in some letters from other equations) until a condition for the maximum radius of orbit is arrived at in terms of other known quantities (mass of planet/star, distance between them). It is an approximation, particuarly as the end bit is a bit of a mathematical trick - it's saying the radius of orbit for the satellite is so small in comparison to the distance from the star that some of the terms in the penultimate equation are neglible and can be dismissed.

Edited by Galactic
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@@Galactic Start the car. Don't stare at the numbers!

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Is it because one is small and one is far away? MUDDY

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@@Sp1n Hahahah! *holds sides

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Q: Is there a scientific conspiracy?

Physicist: Obviously.

Science started in the 1750’s when a cadre of ultra-wealthy nobles decided to use their extreme means to build complex and bewildering devices for the express purpose of, as Mikhail V. Lomonosov put it (in Russian), “… the obfuscation of the truth from all, the befuddlement of the masses, the erosion of spiritual pursuits, and to [waste a lot of] time.”.

Lathe.jpg

Built to befuddle and obfuscate.

In his letters to fellow conspirator Cantor, Newton boasted about their contributions to science and mathematics saying “What we do today, let it not be mistaken, is the most elaborate and vexing gaff ever perpetrated. This truly is a godly joke against which all other humour can scarcely be compared.”.

Within the conspiracy there are supporters and detractors. Einstein, crushed by guilt, finally recanted in 1960 saying (in German) “I made it all up. I thought it would be funny, but then things got out of hand.” At the other extreme are examples like Gallileo, who left his middle finger on display with a plaque that read (in Italian) “May all the Earth sit and spin like a plate upon my bird”. This plaque was later removed, ostensibly for being offensive, but in reality for accidentally revealing a truth about the Earth.

thebird.jpg

Galileo’s only entirely honest statement.

The scientific community didn’t become truly organized until the early 20th century in order to squelch public knowledge of ghosts and telepathy. Today psychic scientists like James Randi use their secret powers to “prove” that other psychics don’t exist by messing up their vibes. During a meeting of the NSF inside their secret volcano lair, NSF director Dr. Córdova was accidentally recorded speaking without her human face mask on: “Tricking people into injecting their children with autism and hiding all the health benefits of coal is easy. That’s Tuesday morning. The hardest part of my job is keeping all the free energy devices off the market.”

The scientific conspiracy was perhaps best summed up by Carl Sagan from the after-life “Why did I do Cosmos? Are you serious? Why did man pretend to go to the Moon? Why do we hide global cooling or make up germs? Why do we systematically spread bizarre and fantastic lies about the nature of all of existence, generation after generation? Because it’s hilarious.”

Source:- http://www.askamathematician.com/2015/04/q-is-there-a-scientific-conspiracy/

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Posted on April 1, 2015

Brilliant! Would have been better if it was posted here on April 1st though ;)

NC

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