71–80 of 116 posts
Earlier quoted context omitted.
AFAIK they're in separate shells so the probability of collision is basically zero.
Things you put in orbit at a certain elevation don't stay at that elevation forever.
Earlier quoted context omitted.
Make the US land area ~20% larger. Randomly place 50,000 shoe boxes up and down the entire eastern seaboard. Randomly place 50,000 shoe boxes up and down the entire western seaboard. Send them in straight lines towards the other side of the country. See if any collide. Almost certainly none of them will. Edit: They will almost certainly For reference, if you placed all 50k boxes next to each other on the same beach,…
By my calculations there will be an average of 500 collisions, no? Each shoebox has an effective width of 2 feet, and with 50k of them that's about 1% density. With 50k in the other direction, and about a 1% collision rate, that's 500 collisions.
Earlier quoted context omitted.
Some info from NASA optical communication page. "Even Earth’s atmosphere interferes with optical communications. Clouds and mist can interrupt a laser. A solution to this is building multiple ground stations, which are telescopes on Earth that receive infrared waves. If it’s cloudy at one station, the waves can be redirected to a different ground station. With more ground stations, the network can be more flexible du…
Seems like reusing some of Star Wars research could be used as well where the beam is constantly adjusted with independent mirrors to keep the beam coherent through the atmosphere. Also learned was the beam itself starts to distort the atmosphere requiring even more adjustments.
Which then also means you have to build ground stations in this range yet far enough apart that they experience different weather yet close enough that you can redundantly link all the sites.
Aside from government and massive telecommunications companies who would this serve?
Earlier quoted context omitted.
Speed matters a lot. You can fit a lot more walking people than speeding motorcycles in the same space. Satellites need to travel at 8 km/s to not fall down.
> Speed matters a lot Not really. You're correct inasmuch as it increases collision energies. But it also increases momentum, which maintains orbital integrity within predictable bounds. Nobody is maneuvering around satellites, they–and their debris–stay where the math tells them to.
Earlier quoted context omitted.
Seems like reusing some of Star Wars research could be used as well where the beam is constantly adjusted with independent mirrors to keep the beam coherent through the atmosphere. Also learned was the beam itself starts to distort the atmosphere requiring even more adjustments.
Wouldn't the angle of the offset matter? It seems like it would make scattering worse to be off-axis by too far. Which then also means you have to build ground stations in this range yet far enough apart that they experience different weather yet close enough that you can redundantly link all the sites. Aside from government and massive telecommunications companies who would this serve?
It's just really cool sci-fi tech that I want to see used in something other than DLP chips!
JWST and other observatories with segmented primary mirrors kind of use the segment alignment one time to get the correct alignment once. Then there is Adaptive Optics. It's kind of the opposite direction though as they are using a laser to detect the distortion so it can be compensated in the image. From learning about SDI when I was a kid/teen, it's just always been about controlling the laser itself in my mind.
Earlier quoted context omitted.
Wouldn't the angle of the offset matter? It seems like it would make scattering worse to be off-axis by too far. Which then also means you have to build ground stations in this range yet far enough apart that they experience different weather yet close enough that you can redundantly link all the sites. Aside from government and massive telecommunications companies who would this serve?
??? It's just really cool sci-fi tech that I want to see used in something other than DLP chips! JWST and other observatories with segmented primary mirrors kind of use the segment alignment one time to get the correct alignment once. Then there is Adaptive Optics. It's kind of the opposite direction though as they are using a laser to detect the distortion so it can be compensated in the image. From learning about S…
Earlier quoted context omitted.
> Speed matters a lot Not really. You're correct inasmuch as it increases collision energies. But it also increases momentum, which maintains orbital integrity within predictable bounds. Nobody is maneuvering around satellites, they–and their debris–stay where the math tells them to.
Thought experiment: Let's say you are simulating ten thousand satellites on your computer, and the simulation runs until there is a crash. Now let's say the simulation runs for an hour normally. If you increase the speed of the simulation, you get to a crash in a shorter time. Satellites move about 30x the speed of airliners. Hence, if everything else was similar, one would expect 30x the amount of collisions.
Not how orbital mechanics work.
Planes maneuvers, get tossed around and have hubs they circle. A plane under my left wing can’t be relied on to continue in a straight line. The satellite can.
Earlier quoted context omitted.
??? It's just really cool sci-fi tech that I want to see used in something other than DLP chips! JWST and other observatories with segmented primary mirrors kind of use the segment alignment one time to get the correct alignment once. Then there is Adaptive Optics. It's kind of the opposite direction though as they are using a laser to detect the distortion so it can be compensated in the image. From learning about S…
The JWST does not have to deal with atmosphere or weather and uses a giant sun shield to keep the internal temperature stable so these alignments have the longevity you need to make the platform work.
Earlier quoted context omitted.
> Speed matters a lot Not really. You're correct inasmuch as it increases collision energies. But it also increases momentum, which maintains orbital integrity within predictable bounds. Nobody is maneuvering around satellites, they–and their debris–stay where the math tells them to.
Orbits are predictable, but they intersect and decay [at different rates] and occasionally get perturbed by space weather. This already needs periodic conjunction avoidance manoeuvres, and whilst orbits are fast satellite manoeuvres are slow , so the notice you need to avoid a conjunction is measured in hours rather than seconds. Can't imagine a scenario in which it would be sustainable for LEO to even approach the d…
I'm not arguing against collisions becoming more likely. I'm arguing aginst it becoming commonplace to the point that it becomes a commercial concern.
> satellite manoeuvres use up a finite supply of expensively-launched propellant
Nobody is plane changing out of a collision. And for the foreseeable future, in LEO, the birds are not propellant constrained. (And launch is getting cheaper.)
> you either need bigger satellites carrying more propellant or have to accept significantly higher collision risk than they currently do
We're decades away from this being a problem. That gives ample runtime to developing e.g. magnetic station-keeping (if we go reactionless) or more-efficient engines.