Originally posted by Ironduke
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Dyson Spheres - Thoughts and Questions
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Originally posted by SteveDaPirate View PostIn theory if you could devise a communication system that could handle the immense distances involved, putting relay satellites in a polar orbit of the Sun should give them an unobstructed view of all the orbital bodies in the system.
The rest of what I've written assumes a relatively tight Sol polar orbit of several million kilometers. If it's possible to have satellites in Sol polar orbit at distances of tens or hundreds of millions km, disregard everything I'm about to write.
As far as space traffic control, reconnaissance, communications, relay, and monitoring satellites are concerned, there would be obstructions if only satellites in Sol polar orbit were utilized for these purposes. Anything the remained on the dark side of an orbital body relative to satellites' positions in this orbit could go unseen and undetected.
A spacecraft could, for example, maintain a position on the dark side of Neptune, and remain completely unseen.
Spacecraft could also possibly hide in the tail of a comet, or keep an asteroid between themselves and the view from such polar orbit satellites, thus being able to travel through the Solar System, potentially undetected.
Hence there would need to be a network of such satellites in orbit around all of the planets, as well as their LaGrange Points, to avoid orbital bodies, asteroids, and comets from being utilized as a means of obstruction from detection and monitoring, and to avoid loss of communications.Last edited by Ironduke; 03 Jun 18,, 20:19."Every man has his weakness. Mine was always just cigarettes."
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Originally posted by SteveDaPirate View PostL4 and L5 are very stable and would require almost no reaction mass to stay balanced and have the advantage of existing at the same distance from the sun as earth does, reducing the need for excessive heating or cooling requirements. However they tend to be so stable that they collect asteroids and dust as well since they form big gravitational bowls that things slide into then can't escape.
Is the density of asteroids and dust in L4 and L5 that much more than the Asteroid Belt? If so, by how much? It makes sense though that there would be more risks of collision to a stationary object in a place such as L4 or L5, than there would be one to an object simply passing through, for example, the Asteroid Belt, even if the density of objects were similar to one another."Every man has his weakness. Mine was always just cigarettes."
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Originally posted by Ironduke View PostIs the density of asteroids and dust in L4 and L5 that much more than the Asteroid Belt? If so, by how much? It makes sense though that there would be more risks of collision to a stationary object in a place such as L4 or L5, than there would be one to an object simply passing through, for example, the Asteroid Belt, even if the density of objects were similar to one another.
You can see below how within the inner solar system the two biggest concentrations of asteroids are either within the asteroid belt itself, or are Trojans captured by Jupiter at the L4 and L5 points. In the second picture you can see a view from the orbital plane that shows how the Hildas (Black) and Trojans (Grey) are distributed vertically as well.
Last edited by SteveDaPirate; 04 Jun 18,, 15:17.
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Originally posted by Ironduke View PostAs far as space traffic control, reconnaissance, communications, relay, and monitoring satellites are concerned, there would be obstructions if only satellites in Sol polar orbit were utilized for these purposes. Anything the remained on the dark side of an orbital body relative to satellites' positions in this orbit could go unseen and undetected.
Originally posted by Ironduke View PostIf it's possible to have satellites in Sol polar orbit at distances of tens or hundreds of millions km, disregard everything I'm about to write.
With the caveat that both operate elliptic orbits with aphelions of around 0.75 AU. The two are due to launch in the next 3-4 months. Parker Solar Probe will only run a single perihelion at that distance (its 22nd, in 2024); Solar Orbiter will stay in its elliptic orbit with that 40 million km perihelion for 3.5 years while raising its inclination through Venus flybys in order to improve coverage of the Solar Poles (from 25° inclination; 34° if extended past 2025).
Originally posted by SteveDaPirate View PostI'd be surprised if the density was anything approaching Star Wars levels.
Among the Neptune Trojan and Greek clouds you interestingly mostly have relatively large objects, and these outnumber the Jupiter Trojan and Greek clouds by an order of magnitude - however there are very few small rocks of a few hundred meters intersparsed between them, making average separation a whole lot bigger.Last edited by kato; 04 Jun 18,, 17:34.
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Originally posted by Ironduke View PostIs the density of asteroids and dust in L4 and L5 that much more than the Asteroid Belt? If so, by how much? It makes sense though that there would be more risks of collision to a stationary object in a place such as L4 or L5, than there would be one to an object simply passing through, for example, the Asteroid Belt, even if the density of objects were similar to one another.
Firstly as far as I am aware objects captured by the Sun's gravitational field and spiraling inwards towards it from the edge of the solar system pick up far too much velocity to be 'captured' by a Lagrange Point. As a result they would pass through one without stopping. The same thing applies to objects in very eccentric orbits around the Sun - on their inwards path they would pick up to much speed to be trapped and would usually be deflected by the gravitational influence of the Earth and Moon in any case.
This would leave a very few rare orbits that would permit random moving objects to be captured long term at any one of the L points. Even then I suspect that over eons there would be forces acting on any such objects that would tend to draw (or push) them towards the edges of the L points whereupon they would resume their travels. Dust grains and other small objects would (I think) be influenced by the impact on solar radiation, magnetic fields and sunlight, all of which would tend to impart subtle velocity changes over time. Larger meteorites etc would over eons also tend to be effected by these and other factors. And of course the further you are away from the the exact centre of an L point the less 'stable' their position would be.
End result (I think) is that Lagrange points wouldn't retain any trapped matter over the longer term (thing millions of years) which explains why, as far as I am aware astronomers haven't detected significant amounts of debris trapped in these zones. This means that man made objects like satellites or space habitats would also probably need station keeping drives at Lagrange points. They would just need to be used very, very sparingly because the forces I am talking about would tend have a negligible effect over a human life time.Last edited by Monash; 06 Jun 18,, 12:58.If you are emotionally invested in 'believing' something is true you have lost the ability to tell if it is true.
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Here's a paper on that: https://arxiv.org/ftp/arxiv/papers/1003/1003.2137.pdf
We find the likelihood of a given planetesimal from [a primordial trans-Neptunian disk] being captured onto an orbit within Jupiter’s Trojan cloud lies between several times 10^-6 and 10^-5. For Saturn, the probability is found to be in the range <10^-6 to 10^-5, whilst for Uranus the probabilities range between 10^-5 and 10^-4. Finally, Neptune displays the greatest probability of Trojan capture, with values ranging between 10^-4 and 10^-3.
Jupiter's capture mechanism is outlined on page 8.
The Trojan populations of Saturn, and those that Jupiter didn't keep stable (75% of captures leaving again within 4 billion years) became the centaurs and short-period comets:
Consequently, taken together, the lost Trojans of Jupiter and Saturn probably contained 3-10 times the current mass of observed Jovian Trojans, which implies the release of ~3x10^-5 - 10^-4 M⊕ of material onto unstable orbits over the time since planetary migration ceased. On the other hand, the loss of Uranian and Neptunian Trojans probably amounted several tens or even hundreds times 10^-5 M⊕, thus providing an important additional source of material on unstable orbits among the giant planets. Such unstable wanderers are known as the Centaurs, and represent the direct parent population of the Jupiter family of comets.Last edited by kato; 06 Jun 18,, 13:54.
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It's looks like in future can be found powerful sources of energy which is no need to build a soccer ball of size of the Sun... It's same as in the past peoples have no any idea about nuclear power, earlier they have no idea even about the processes which producing energy from the chemical reaction. For now peoples knows a lot, for an example the annihilation process, so who knows, maybe in future peoples can create some extremely powerful energy sources...
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