For those of you familiar with Lagrange''s mathematics, heres an interesting question. NASA has already put a Telescope on one of the Earth''s many Lagrange points, and if remains fairly stable. We know that there are "Trojan" Asteroids that follow earth''s orbit around the sun, and the moon''s orbit around the earth, and many of the other planets orbits. The question is, if you wanted to put an inhabitable planet (assume the constants of this formula are earth''s measurements) in the Trojan Lagrange Point of a Gas Giant, what type of scenario would you need? Obviously, the Gas Giant would have to be at 1 AU out, since the NeoEarth itself would need to be 1 AU out. Also, the tidal forces on NeoEarth would be tremondous, and it would need it''s own moon (or set) to counteract the tidal force. But, what kind of moon, or how many? How big of a gas giant is too big? Do we need a Jupiter sized one, or would a Saturn sized one work? In relation to Gameplay, this is like asking what would you need to put a Ring around the Sun (XBOX-Halo), just so you can''t dismiss my question that fast.

To have a Lagrange point, you need a minimum of 2 astral bodies. The points are the gravitical intersections where gravity becomes nullified.

Like Newton said, the gravity interaction between two bodies decreases with the square of their distance, something like:

g = (mA * mB) / (d*d)

Now you need to find the Cartesian point where your planet would "feel" the same attraction towards the nebula, AND towards the other astral body, serving as stabilizer...

Sorry if i couldnt be more clear...

[Hugo Ferreira][Positronic Dreams]
All your code are belong to us!

Theres a flaw in your basics, in that you can't have a gas giant at 1 au. In order to have a gas giant the planet needs to be far enough from the sun in order for stellar forces to be weak enough to cause the gas giant to form.

What you could have instead is the gas gaint has a moon with highly dense atmosphere so that it retains enough solar heat to keep the moons average temperature similar to thats at of earths.

Also A trojan asteroid is one thats orbit intersects earths orbit. but that not really important.
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Chaos Factor Design Document



[edited by - TechnoGoth on September 14, 2003 7:48:05 PM]

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Original post by TechnoGoth
Theres a flaw in your basics, in that you can''t have a gas giant at 1 au. In order to have a gas giant the planet needs to be far enough from the sun in order for stellar forces to be weak enough to cause the gas giant to form.

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I don''t know where you got that idea from. We''ve already discovered planets with much higher mass than Jupiter with orbital radii smaller than 1 AU (click here for a chart) this one for example, is more than 14 times the mass of Jupiter, and less than a tenth of an AU from it''s star.

However I don''t see why your gas giant has to be exactly 1 AU: it could be orbiting a brighter star than our sun.

quote:

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Original post by Inmate2993
Obviously, the Gas Giant would have to be at 1 AU out, since the NeoEarth itself would need to be 1 AU out. Also, the tidal forces on NeoEarth would be tremondous, and it would need it''s own moon (or set) to counteract the tidal force. But, what kind of moon, or how many? How big of a gas giant is too big? Do we need a Jupiter sized one, or would a Saturn sized one work?

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The tidal forces wouldn''t be that big a deal. The gas giant would be about the same distance as the sun, 93M miles or so. The mass of the sun completely dwarfs a gas giant with mass of even jupiter. A saturn-sized object would have less mass than our saturn, because the sun puffs up gas giants this close in. It would be very bright although not as bright as the moon.

I think Mars and Venus would go bye-bye in some millions of years but Neo-Earth would be in a stable position.

I don''t think it will matter for gameplay. It''s just a visual.

Instead of a gas giant, you could have a binary star system. Of course your planet would be in perpetual daylight (or twilight) with no real night.