No Job Is Too Small for Compact Geostationary Satellites(spectrum.ieee.org)
spectrum.ieee.org
No Job Is Too Small for Compact Geostationary Satellites
https://spectrum.ieee.org/aerospace/satellites/no-job-is-too-small-for-compact-geostationary-satellites
33 comments
You can't compete with Starlink from GEO, the latency to GEO is just too high - around 250ms - which is ok for some purposes but pretty crap compared to ground fiber or Starlink.
The article says they are market maker of satellite bandwidth, so they have data that their venture have paying customers. They mentioned that the purpose of the satellite is to augment bandwidth when needed and move to another location.
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People add garbage to the orbit before thinking how to remove it. As with anything new actually. Do first and think how to undo later
My belief is that (within limits) the rule about smallsats and LEO is different: you don't need planned de-orbit because they have short persistence due to drag and almost no significant hit-the-ground risk because they burn up.
GEO has to have de-orbit burns or parking orbit. Different. And it is governed by law, within the limits.
GEO has to have de-orbit burns or parking orbit. Different. And it is governed by law, within the limits.
FWIW, junk in LEO can still remain for dozens or even hundreds of years.
Most satellites also don't burn up completely. At least in the US, the current standard is that the odds of a casualty in case of uncontrolled reentry are less than 1 in 10,000. I think that as we see a proliferation of LEO constellations with tens of thousands of smallsats (some of which are almost surely going to be operated by companies that go bankrupt), that standard is going to bite someone in the ass.
Most satellites also don't burn up completely. At least in the US, the current standard is that the odds of a casualty in case of uncontrolled reentry are less than 1 in 10,000. I think that as we see a proliferation of LEO constellations with tens of thousands of smallsats (some of which are almost surely going to be operated by companies that go bankrupt), that standard is going to bite someone in the ass.
I think one death total, to save megabucks on each of hundreds or thousands of satellites, is an OK situation.
I think 1 in 10,000 is high, there's a lot of land out there, and sea.
It almost seems like you would have to try really hard if you want a 0.0001 chance of hitting a person on deorbit.
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Small satellites have a high surface area to mass ratio and thus decay due to drag much faster. I.e. on the order of a few years at most.
What are you considering small or a few years? Smallsats like Starlink is using can take 100+ years to deorbit from drag in LEO (at the 1100km orbits they haven't started deploying to yet— for the orbits they're currently using the deorbit time is on the order of a few years). Even if you're talking about 1U cubesats (~1kg and 10cmx10cmx10cm), those can take decades. The first cubesats ever built are still on orbit.
Going even smaller, there are still small droplets of coolant in LEO from nuclear reactors that the USSR launched 50 years ago. The droplets are more or less spheres with diameters in the 5mm-5cm range.
Going even smaller, there are still small droplets of coolant in LEO from nuclear reactors that the USSR launched 50 years ago. The droplets are more or less spheres with diameters in the 5mm-5cm range.
This is fascinating. What are (or were) those reactors for?
There were used to power Soviet reconnaissance satellites that used radar to track ships. The satellites themselves were in really low orbits (~200km), and they didn't want to use solar panels due to additional drag and inability to generate power at night. When the satellites were deactivated, they were supposed to eject their nuclear reactors (actual nuclear reactors, not RTGs[1]) to a higher orbit before the satellite reentered. The program had a number of "oopsies". A lot of the reactors leaked, and are actually one of the biggest sources of space junk today. I think they were the #1 source of space junk before China's antisatellite weapon test.
The biggest oopsie was when some of the satellites malfunctioned and weren't able to eject their reactors. One of them landed in the ocean. The other didn't— it ended up spreading radioactive debris across a good chunk of northern Canada. Some of the pieces of debris where radioactive enough to cause serious harm, so it was fortunate that the junk landed in unpopulated areas.
[1]: RTGs are how most nuclear powered things in space generate electricity— https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
The biggest oopsie was when some of the satellites malfunctioned and weren't able to eject their reactors. One of them landed in the ocean. The other didn't— it ended up spreading radioactive debris across a good chunk of northern Canada. Some of the pieces of debris where radioactive enough to cause serious harm, so it was fortunate that the junk landed in unpopulated areas.
[1]: RTGs are how most nuclear powered things in space generate electricity— https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
The title is specifically about GEO satellites
Compact GEO.. GEOO..... (sigh) good point. So they're not in unregulated space (does that even exist?) and have to have a de-orbit or park policy and understand how to effect it, and are governed by the economy they launch from and the territory they fly over, and the risk of litigation from other GEO owners affected by their policy.
The geostationary satellites are usually moved to a Graveyard Orbit when they are not longer used. The spots in the geostationary are very few and very regulated. More info in https://en.wikipedia.org/wiki/Graveyard_orbit
How do you know whether these companies are thinking about it? There is nothing in the article about this.
The article mentions when and how one of the satellites will be disposed of.
But the volume of all possible geostationary orbits is MASSIVE, much much larger than volume of LEO orbits.
The volume of geostationary orbits is theoretically zero, it's a 2D circle. It's true that most applications can work within some tolerance around that mathematically perfect orbit, and it's also true that volume of all orbits at all inclinations near geostationary altitude is huge. I'll grant those caveats, but I don't think it's at all sensible to waste the best parts of those orbits, especially given the deorbit timelines. It's one thing to gamble with Kessler syndrome that will last a couple decades and cut off our generation from LEO, another if it lasts for millennia and cuts off our civilization from GEO.
There was an episode[0] on French radio show "La méthode scientifique" in October 2019 about these questions (following a near-collision between SpaceX and ESA satellites where apparently SpaceX just played dead and ESA people had to maneuver).
They talked about a lot of things, but IIRC GEO issues were very low on their priority list. This is a very thin doughnut but still a very very large on considered scales.
[0] In French: https://www.franceculture.fr/emissions/la-methode-scientifiq...
They talked about a lot of things, but IIRC GEO issues were very low on their priority list. This is a very thin doughnut but still a very very large on considered scales.
[0] In French: https://www.franceculture.fr/emissions/la-methode-scientifiq...
The volume of geosynchronous orbits is massive, but because geostationary orbits are limited to a single plane the available volume for them is quite small.
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Space exploration is still in its infancy. This is like yelling at a kid for throwing a baseball too hard into the air and it not coming back down.
"Timmy! People have to fly up there! What is wrong with you? Why didn't you think about that before you decided to throw the ball?"
Up until recently mankind lived by a "what goes up must come down" understanding of physics. We need to add an amendment.
"What goes up must come down. Unless you throw it really, really hard, then actually, it might never come back down."
"Timmy! People have to fly up there! What is wrong with you? Why didn't you think about that before you decided to throw the ball?"
Up until recently mankind lived by a "what goes up must come down" understanding of physics. We need to add an amendment.
"What goes up must come down. Unless you throw it really, really hard, then actually, it might never come back down."
50 years ago this was a valid point. Human usage of earth orbits is mature and has been for a long time.
Also it is very likely tugs will be deploeyd in the future to drag dead satellites back to a space station for reprocessing.
Mass does not grow on trees in the empty void of space, so reusing those is s no brainer. And the bit of noble gas your solar electric tug is gling to use up for that is negligable compared to all the effort spent to drag it all out of abgravity well or get the raw materials all they was from an asteroid, not to mention all the elaborate processing needed.
Mass does not grow on trees in the empty void of space, so reusing those is s no brainer. And the bit of noble gas your solar electric tug is gling to use up for that is negligable compared to all the effort spent to drag it all out of abgravity well or get the raw materials all they was from an asteroid, not to mention all the elaborate processing needed.
My understanding is that this would only make sense for satellites in the same orbital plane as the debris.
We'd actually like things that have no use sticking around up there to come down, though.
I definitely felt that before at my previous work
The article only mentioned communications satelites and I don't think anyone is going able to beat Starlink in that area in the next 5-10 years.