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we need traffic lights for satellites
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madires:
ESA had to perform a collision avoidance manoeuvre for Aeolus because of SpaceX' Starlink:
https://twitter.com/esaoperations/status/1168533241873260544

SpaceX Refused To Move A Starlink Satellite At Risk Of Collision With A European Satellite:
https://www.forbes.com/sites/jonathanocallaghan/2019/09/02/spacex-refused-to-move-a-starlink-satellite-at-risk-of-collision-with-a-european-satellite/#6e2c36d51f62

Aeolus is a little bit longer in space than the Starlink satellite. So we can guess what will happen with tons of LEO internet satellites and SpaceX' attitude. :palm:
Ysjoelfir:
Naaaah, just build a three dimensional matrix of hyperloopses in space for every sattelite out there. Problem solved. It will only cost 1$ for a sat to travel through the loop!
bd139:
Raytheon have a decent solution for this in development. It's called the MOKV, the Multiple Object Kill Vehicle  :-DD
nuclearcat:
As i understand they have quite weak Krypton thruster, and it can operate only some time on each turn (90min), i guess only when panels are insolated.
They have single panel, again according "internet sources" approx 3kW, thruster according to publicly available data on efficiency can provide approx 150 millinewtons.
Weight of satellite is approx 227kg.
Current orbit according to article 320km.
It means 7718.27m/s current orbital speed. Just if they raise orbit 10km they will have orbital speed 7712.51m/s, and need ~24h of continuous engine operation, taking in assumption ESA tweet "The manoeuvre took place about 1/2 an orbit before the potential collision. "
I have some doubts that we can say these satellites have proper collision avoidance capabilities.
Does anyone have more info?

To test my theory i took this data on their orbit change maneuer.

--- End quote ---

According to news orbit raise maneuver was (very approximately) from 2019/05/27 to 2019/06/14, 19 days. If we assume data above is correct, they need to run at least 56% of time such thruster.
On the orbit 440km satellite will spend in shadow (keeping in mind atmosphere attenuation too) t=τ*(2θ)/(2π)m where is τ = orbital period θ = arcsin(r/(r+h)) (r is 6371 + 100) approx 39% of all time.
It looks like close to true...

Knowing how I am prone to make horrible mistakes in numbers and how in a hurry i wrote this assumption - maybe I wrote nonsense above :)
schmitt trigger:

--- Quote from: bd139 on September 03, 2019, 02:43:09 pm ---Raytheon have a decent solution for this in development. It's called the MOKV, the Multiple Object Kill Vehicle  :-DD

--- End quote ---

Which, instead of a single object one would have to watch for, would generate thousands of fragments creating a lethal shrapnel cloud orbiting the earth.

As a matter of fact the Chinese military performed such a test a few year ago, and created such an orbiting hazard.
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