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When plants align
#21
RE: When plants align
(March 13, 2015 at 4:17 pm)Smaug Wrote: By the way, what form of equations of motion did you use in your simulation on a C64?

I think the one I had on my Commodore could have been this one: http://www.ebay.com/itm/Visible-Solar-Sy...4042&rt=nc

Altho, I am not 100% sure. I remember it was on a carthridge. And I think I remember the picture.
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#22
RE: When plants align
(March 13, 2015 at 4:44 pm)Void Wrote: Altho, I am not 100% sure. I remember it was on a carthridge. And I think I remember the picture.

Thanks! I never had a C64 actually so I thought it wasn't pre-programmed but there was a possibility to programm the computation by yourself.
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#23
RE: When plants align
(March 13, 2015 at 4:55 pm)Smaug Wrote: Thanks! I never had a C64 actually so I thought it wasn't pre-programmed but there was a possibility to programm the computation by yourself.

Probably... Only I was seven or eight years old that time. And still today I would have no idea how to do that. xD
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#24
RE: When plants align
(March 13, 2015 at 4:17 pm)Smaug Wrote: By the way, what form of equations of motion did you use in your simulation on a C64?

I didn't actually use a C64 there. That was just a stock photo from google.

I did do a project in my Orbital Mechanics class in college of a 3 body problem modeled in MATLAB.
"There remain four irreducible objections to religious faith: that it wholly misrepresents the origins of man and the cosmos, that because of this original error it manages to combine the maximum servility with the maximum of solipsism, that it is both the result and the cause of dangerous sexual repression, and that it is ultimately grounded on wish-thinking." ~Christopher Hitchens, god is not Great

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#25
RE: When plants align
(March 13, 2015 at 8:19 pm)SteelCurtain Wrote: I did do a project in my Orbital Mechanics class in college of a 3 body problem modeled in MATLAB.

May I wonder, did you consider a restricted problem or a general case?

It's well known that it's generally impossible to solve rigorously the Cauchy problem for three bodies, too. So you either go with five known solutions or use numerical simulation. Numerical simulation also possesses a set of serious problems. Among them is determining the periodic solutions.
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#26
RE: When plants align
(March 12, 2015 at 9:54 pm)Void Wrote: I think that someone with the right knowledge would be able to calculate if it is possible. It could be that two planets have a certain speed so that it would be impossible for them to line up. I don't know.

But I am also thinking that all the planets on one side could cause a powerful gravity reactoin on the sun. For all I know, all kinds of funny things could happen. Maybe even the combined forces would cause one or more of the outer ones to fly out into the milky way?

The combined mass of all of the planets is a tiny fraction of the mass of the Sun. Nothing untoward would occur.
Skepticism is not a position; it is an approach to claims.
Science is not a subject, but a method.
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#27
RE: When plants align
(March 12, 2015 at 9:41 pm)Void Wrote: This is just an absurd question, but I kind of thought it was funny, so I'm just gonna pop it.

I was thinking that in a world with infinite posibilities, there would be a chance that one religion actually was right. I kind of thought the odds of that would be about the same as having all the plants in the solar system line up in one straight line on one side of the sun.

The question is, will that ever happen, or have happened in the past? And if it is possible, how would that affect the physics of the sun and the solar system?

The answer depends on how precisely do the planets have to line up for you to consider them to be "lined up".

If you require a single straight line to pass through all planet, that almost certainly has never happened, nor will ever happen. The reason is the solar system is not a flat plane. The plane of each planet's orbit is slightly different. The degree of inclination is small but when multiplied by interplanetary distances the absolute up and down movement of any planet is large compared to the size of the planet. The planes of different planetary orbits intersect along lines of different orientation. So there is no location anywhere along any orbit where planes of more than 2 planetary orbits intersect. So even if all planets fall precisely on a single straight line when viewed top down from above the solar system - in itself an extremely unlikely event - no matter what the orientation of that line is in the horizontal plane, those same planets would never be aligned on a straight line when looked at edge on.

On the other hand, if you relax your definition of lined up to mean, for example, all 8 planets occupying the same 45 or 90 degree slice of arc around the sun when viewed top down, then yes, it has happened many times before and will happen again many more times.
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#28
RE: When plants align
(March 14, 2015 at 9:18 am)Chuck Wrote: The answer depends on how precisely do the planets have to line up for you to consider them to be "lined up".

If you require a single straight line to pass through all planet, that almost certainly has never happened, nor will ever happen. The reason is the plane of each planet's orbit is slightly different. The planes of different planetary orbits intersect along lines of different orientation, so even if all planets seem to align when viewed top down from above the solar system - in itself an extremely unlikely event - they won't be aligned when looked at edge on.

On the other hand, if you relax your definition of aligned to mean, for example, all 8 planets occupying the same 45 or 90 degree slice of arc around the sun when viewed top down, then yes, it has happened many times before and will happen again many more times.

To add to what you've said, the relaxed case is called an Appulse or Parade of planets. It's such a case when all the planets appear in a narrow sector (with an angle of 10 to 40 degrees) of the celestial sphere. There are different kinds of appulses depending on how and how many planets are aligned. An appulse of all the planets happens with a period of about 170-200 years as far as I remember.

As for the conjunction of all the planets, it's mathematically possible but is extremely unlikely indeed. Speaking of inclinations of orbits, it's possible that due to precession and deformation the orbits align in such a configuration when the conjunction is possible in a rigorous sence. But due to the chaotic nature of Solar system's behaviour such an event is technically impossible to predict.
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#29
RE: When plants align
(March 13, 2015 at 4:39 am)Smaug Wrote: A conjunction of all the planets is possible though by definition it's an extremely rare ocasion. I don't know by heart whether such a thing has ever taken place or what is the period and don't bother to look it up right now. Speaking of it's effect on the Solar system, the effect is extremely minor even on a relatively long run due to the rarity of such conjunctions .

On further review, I'm coming into agreement with the OP:
(March 12, 2015 at 9:41 pm)Void Wrote: I was thinking that in a world with infinite posibilities, there would be a chance that one religion actually was right. I kind of thought the odds of that would be about the same as having all the plants(sic) in the solar system line up in one straight line on one side of the sun.
Where, suppose you will only accept that all planets in line means that each planet must be some exceptionally small distance (say, planck length) from a gravitationally warped geodesic in spacetime. Then the chances of this occurring is roughly equivalent to one religion being entirely accurate, say 1 chance in ten to the gazillionth and not to be expected in any reasonably arguable lifetime of the universe.
My expectation that it would not have any substantial effect other than 'oh, wow, that's neat!' stands.
So how, exactly, does God know that She's NOT a brain in a vat? Huh
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#30
RE: When plants align
(March 13, 2015 at 4:39 am)Smaug Wrote: When two or more orbiting bodies align in line on the same side of a central body it's called conjunction. When two orbiting bodies are in conjunction their mutual gravitational attraction is the strongest of all other orbital configurations. Conjunctions play a major role in so-called orbital resonances. A resonance occurs when the periods of two or more orbiting bodies relate as small natural numbers. Resonant configurations lead to regular variations of gravitational interaction between the orbiting bodies which in turn leads to periodic and/or secular variations of the bodies' orbits. The variations are ralatively small but on a long run they may result in either stabilzation of orbits or in ejections or collisions of celestial bodies.

Speaking of aligned plants... it's a good point for the astrologists that eight plants aligned in line and placed not far from them affect them stronger (via gravitational pull) that eight planets aligned in a conjunction.

A conjunction of all the planets is possible though by definition it's an extremely rare ocasion. I don't know by heart whether such a thing has ever taken place or what is the period and don't bother to look it up right now. Speaking of it's effect on the Solar system, the effect is extremely minor even on a relatively long run due to the rarity of such conjunctions .

Smaug is quite correct here. Conjunctions are common and their effect is quite minor (other than as he notes, conjunctions have an effect on orbital resonances).

It's important to note a few things in addition to what he is saying. One, is that a conjunction doesn't mean the planets are all in a straight line, but rather that they're approximately in the same region of sky.

Second, that there is no common orbital plane - excluding Pluto, the other major planets' inclination ranges from about a degree to over seven degrees relative to earth, and Pluto's orbital inclination is seventeen degrees. Including other Pluto-sized trans-Neptunian objects makes the situation only worse. Even if you limited it to the naked-eye visible planets known to the ancients, the type of precise conjunction the OP seems to be alluding to seems quite unlikely to impossible.
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