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To: Ilaine who wrote (7720)	8/26/2001 1:48:34 AM
From: Don Lloyd	Read Replies (2) \| Respond to of 74559

CB - ...I find it hard to believe you don't know why GEO satellites are capable of carrying a larger payload than LEO satellites. Gravitational pull is affected by mass and distance. The bigger the mass, the greater the gravitational pull. The further the distance between the masses, the less the gravitational pull. For an object of the same mass, the further the distance, the less the pull. The closer the distance, the greater the pull. LEO satellites orbit closer to the earth, so to keep from being pulled out of orbit, they are made smaller. The devices which you describe to pull the satellite back into orbit obviously work better on smaller satellites, because they use a great deal of energy. It's not like waving a magic wand. No, I am not a rocket scientist, and neither are you. Everything I know about satellites I learned from real rocket scientists. ... The definition of a stable orbit is that the pull of gravity bends the trajectory of the satellite into a unique closed path that maintains a constant total of kinetic and gravitational potential energy without requiring any propulsion or fuel use at all, independent of orbital height. Fuel is needed for station keeping, and LEO satellites probably suffer from atmospheric drag, requiring compensation. The size of a satellite is a matter of economics. The smaller the satellite and the less the combined mass of the satellite and its fuel, the cheaper the launch cost to orbit. No satellite is likely to be designed to be larger than its purpose requires, and for small enough satellites, multiple satellites can be deployed from a single launch vehicle. Regards, Don Not a rocket scientist either.

To: Ilaine who wrote (7720)	8/26/2001 2:15:28 AM
From: Maurice Winn	Read Replies (2) \| Respond to of 74559

CB, I am going to copy your post over to the Globalstar thread [people over there need a good laugh given the financial damages they've suffered]. What you wrote really was funny to geeky technoids. I'm not intending to flog a dead horse, but when you write stuff which is wrong, I do have the energy [for now] to correct it for you and readers who might misunderstand how things really work. It's the photovoltaic wings which make the satellites stay up, not the fuel on the satellite being used to push them up. GEOs have bigger photovoltaic wings because the atmosphere is thinner way out there. They also need more light to generate more electricity, [one of nature's happy balances], LEOs have smaller wings because there's more air down low and radio transmission distances are shorter [the power required being the square of the distance]. That's why submarines have really little wings and 747s have bigger ones [water is very dense and air is less dense - submarines are also buoyant even though they are made of steel and sink regularly]. You are not convincing me that you knew why Globalstar went kaput if you don't know what keeps the satellites up. Actually, [seriously], just a couple of weeks ago it occurred to me that a lot of people actually wouldn't have a clue what keeps a satellite up there. I guess I was right. You are right, I am not a rocket scientist. Everything I know about satellites, I make up for fun. Did a real rocket scientist tell you about what keeps satellites up there? She was wrong, it's the photovoltaic panels. Scientifically speaking, Mqurice PS: Kepler's law is "The bigger the photovoltaic surface, the bigger the satellite and the higher it flies". Ask IT if I am right. Also, it's okay to discuss Globalstar here as it's directly related to the Great Financial Collapse of 2001, as Jay pointed out. Fractal forms suggest Globalstar as a microcosm of the whole world since the same drives which lead to the Globalstar failure apply to everything. Did you know for example that Globalstar's Zenit crash directly caused the Long Term Capital Management crash and the subsequent international financial gyrations which were primed, ready for a butterfly to crash [instead of taking off] in a Russian forest? Jay was percipient to see the connection of Globalstar to the whole. I was very impressed. He makes me very nervous.

To: Ilaine who wrote (7720)	8/26/2001 3:35:04 AM
From: FaultLine	Read Replies (2) \| Respond to of 74559

The closer the distance, the greater the pull. LEO satellites orbit closer to the earth, so to keep from being pulled out of orbit, they are made smaller. CB, Sorry but I cannot contain myself. You are seriously incorrect on this issue. --fl

To: Ilaine who wrote (7720)	8/26/2001 11:27:22 AM
From: dwight martin	Read Replies (1) \| Respond to of 74559

"Everything I know about satellites I learned from real rocket scientists." Manny, Moe, and Jack? Larry, Moe and Curly? George W. Bush?

To: Ilaine who wrote (7720)	8/26/2001 10:05:13 PM
From: Wildstar	Read Replies (1) \| Respond to of 74559

>>>LEO satellites orbit closer to the earth, so to keep from being pulled out of orbit, they are made smaller.<<< Not true. When an object is in orbit around the earth, two forces are balanced - the force experienced by an object traveling in a circular path and the force of gravity. The force experienced by an object traveling in a circular path is given by the equation F = mv^2/r and points away from the earth. The gravitational force is given by F = GMm/r^2 and points toward the earth. In these equations, G = universal gravitational constant M = Mass of the Earth m = mass of the object r = distance from the center of the Earth v = velocity of the object When an object is in orbit, the two forces are balanced, such that the object neither falls to the earth nor escapes its gravity. Therefore, GMm/r^2 = mv^2/r The first thing that is apparent is that m, the mass of the object, appears on both sides of the equation in the numerator, and therefore is eliminated. The final equation governing the motion of the object in orbit is: v = SQRT (G*M/r) For a given object orbiting the earth, the only variables are the object's velocity and its distance away from the earth (because universal Gravitational constant and the Earth's mass are constant). The object's mass has nothing to do with it. Low earth orbit satellites, because their r is smaller, have to have a greater v. But their mass is not restricted by their low orbit. Edit - one more note: It takes energy (fuel) to reach orbital velocity, but once the object reaches orbital velocity, no fuel is needed to keep the object in orbit, assuming the effect of air resistance is negligible. Air resitance plays a greater role nearer to the Earth of course, and I don't know if LEO's are low enough for this to be a factor.

To: Ilaine who wrote (7720)	8/27/2001 12:45:22 AM
From: LLCF	Read Replies (1) \| Respond to of 74559

<. Nevertheless, I find it hard to believe you don't know why GEO satellites are capable of carrying a larger payload than LEO satellites.><Gravitational pull is affected by mass and distance. The bigger the mass, the greater the gravitational pull. The further the distance between the masses, the less the gravitational pull. ><Sorry I struck a nerve, but pissing on me isn't going to make your money come back.;^> GEFAW!!!!!!!!! Are you kidding me! Give it up! The was featured in Magazines he made so much money on the subject!!! That's just awesome! ROFLMAO DAK