Such obnoxious Claudish in this article. I don't know enough verify the analysis and I genuinely don't know if the author does either.
walrus01•32m ago
It also doesn't "know" basic orbital mechanics.
From the article:
> and station-keeping burns corrupt them
Geostationary satellites execute station keeping burns to avoid "wandering", from the POV of an observer on the ground.
Something like a satellite in a Lagrange point might also execute tiny station keeping burns.
A LEO satellite such as starlink has thrusters, yes, and it executes burns, yes, but its burns are executed prograde in the direction of travel to increase orbital altitude. Likely in several small burns. A single prograde burn made when on one side of the planet has the effect of increasing the height of apogee on the opposite side of the planet, so after you do your first burn and are halfway around a full orbit, you need to do at least a second burn to re-circularize your orbit.
Nobody that's involved in LEO satellite operations would call it a station keeping burn because it's literally not keeping station anywhere.
I also doubt the validity of the data in this article because without internal information from spacex on things like how often they burn, when they burn, duration of burn and expected delta-v gain per burn (which spacex is OBVIOUSLY not going to share with anyone because making an extremely fuel efficient small satellite is a competitive advantage and a trade secret), you can't know how much the satellites are actually thrusting in any given day, week, month or year to account for varying increased atmospheric density.
The one thing that the article did get right is that the superdove satellites, which are 3U cubesats, have no thrusters at all, so watching the degradation of their orbit over time (and the rate of change in any given week or month) might be a more valid source of data. There's no need to "guess" at what a satellite operations center at SpaceX might be commanding them to do in terms of fuel expenditure because there is no fuel to expend or thrusters to turn on to burn prograde.
jubilanti•41m ago
walrus01•32m ago
From the article:
> and station-keeping burns corrupt them
Geostationary satellites execute station keeping burns to avoid "wandering", from the POV of an observer on the ground.
Something like a satellite in a Lagrange point might also execute tiny station keeping burns.
A LEO satellite such as starlink has thrusters, yes, and it executes burns, yes, but its burns are executed prograde in the direction of travel to increase orbital altitude. Likely in several small burns. A single prograde burn made when on one side of the planet has the effect of increasing the height of apogee on the opposite side of the planet, so after you do your first burn and are halfway around a full orbit, you need to do at least a second burn to re-circularize your orbit.
Nobody that's involved in LEO satellite operations would call it a station keeping burn because it's literally not keeping station anywhere.
I also doubt the validity of the data in this article because without internal information from spacex on things like how often they burn, when they burn, duration of burn and expected delta-v gain per burn (which spacex is OBVIOUSLY not going to share with anyone because making an extremely fuel efficient small satellite is a competitive advantage and a trade secret), you can't know how much the satellites are actually thrusting in any given day, week, month or year to account for varying increased atmospheric density.
The one thing that the article did get right is that the superdove satellites, which are 3U cubesats, have no thrusters at all, so watching the degradation of their orbit over time (and the rate of change in any given week or month) might be a more valid source of data. There's no need to "guess" at what a satellite operations center at SpaceX might be commanding them to do in terms of fuel expenditure because there is no fuel to expend or thrusters to turn on to burn prograde.
https://www.google.com/search?client=firefox-b-d&q=superdove...