Longer term crusing and internet access to earn a crust

[Kelpie]

The light pollution aspect is potentially serious. I don't think space junk is a problem at lower orbits though- a dead Starlink will re-enter in about five years or so, as would any associated debris from collisions or explosions.

 

[DownWest]

I sometimes boggle at the knowledge on posts here.
Thanks to everybody for updating my megre understanding of recent stuff.

 

[JumbleDuck]

The light pollution aspect is potentially serious. I don't think space junk is a problem at lower orbits though- a dead Starlink will re-enter in about five years or so, as would any associated debris from collisions or explosions.

I get the impression it's live ones, not dead ones, which are causing worry, as it's getting harder and harder to find a clear bit of space to shoot a rocket through.

 

[Kelpie]

I get the impression it's live ones, not dead ones, which are causing worry, as it's getting harder and harder to find a clear bit of space to shoot a rocket through.

I'm not too sure where you get that impression from. Space is big. Famously, notoriously big.
Think about how big the surface area of the Earth is. Every orbital altitude offers that same area, except a bit bigger, increasingly so as you go to higher altitudes. And there are essentially an infinite number of altitudes to choose from.

We manage to fit every single ship, car, and train onto the surface of the Earth... alongside every house, factory, forest, desert, etc. 1500 satellites may sound like a lot, but it's not much compared to what we manage to cram onto the surface of the Earth.

One caveat- geostationary orbital slots are finite, because you are constrained to a set altitude and inclination- in effect you only have a single circular line in which to place the sats. It is a line 165,000 miles long, so you can fit a lot of satellites on it, but much of it lies over the ocean and there is competition for the more useful slots.

 

[mjcoon]

We manage to fit every single ship, car, and train onto the surface of the Earth... alongside every house, factory, forest, desert, etc. 1500 satellites may sound like a lot, but it's not much compared to what we manage to cram onto the surface of the Earth.

And yet ships, cars and trains collide, and aircraft with their extra degree of freedom. Although the bits don't, mostly, fly off and hit other vehicles. Are there collision avoidance rules for satellites? They can't afford much manoeuvring, owing to the lack of refuelling stations...

Mike.

 

[Kelpie]

And yet ships, cars and trains collide, and aircraft with their extra degree of freedom. Although the bits don't, mostly, fly off and hit other vehicles. Are there collision avoidance rules for satellites? They can't afford much manoeuvring, owing to the lack of refuelling stations...

Mike.

Vehicles do collide, but there are so many of them. Many orders of magnitude more than there are satellites. E.g. compare an estimated 1,400,000,000 cars with the current <5000 satellites.
There certainly are collision avoidance procedures for satellites, and avoidance manoeuvres are quite routine. If done a few days ahead, It takes only a tiny change in velocity to totally eliminate a collision risk. More and more satellites these days use electric propulsion, which uses about a tenth of the propellant that conventional systems require. Most operators also consider end-of-life disposal, which for low orbits means re-entry, and for higher orbits means parking in a 'graveyard' slot.

The biggest risk is where two dead spacecraft are on a collision course, as neither one can move out of the way. However even here progress is being made- earlier this year an experimental satellite grappled on to a 20 year old Inmarsat and moved it to a different orbit, extending its useful life. The same technology could be used to deal with dead satellites, unless they are spinning out of control.

 

[ryanroberts]

I'm no sailor yet and also a tech worker, but I'm really not sure I want broadband internet in the during or even at the end of a lot the voyages I dream about. Combining messing about in a small boat with employment is unfortunately a necessity.

 

[JumbleDuck]

I'm not too sure where you get that impression from. Space is big. Famously, notoriously big.
Think about how big the surface area of the Earth is. Every orbital altitude offers that same area, except a bit bigger, increasingly so as you go to higher altitudes. And there are essentially an infinite number of altitudes to choose from.

We manage to fit every single ship, car, and train onto the surface of the Earth... alongside every house, factory, forest, desert, etc. 1500 satellites may sound like a lot, but it's not much compared to what we manage to cram onto the surface of the Earth.

True, but ships, cars and trains are not doing 7.8km/s (current ISS speed). And if they hit each other they don't break up into thousands of pieces doing similar speeds and just as capable of causing problems. An old but relevant article from "The Verge": As satellite constellations grow larger, NASA is worried about orbital debris

PS You may think it's a long way down the road to the chemists, but that's just peanuts compared to space. Listen ...