I came across the orbital data for a low Earth orbit spacecraft and one thing which I am not able to understand is why does its Right Ascension of ascending node and Argument of Perigee keep changing every day.
Firstly, it seems extremely unrealistic to me, that they are being changed by manoeuvring the spacecraft because:
- They are very costly affairs and for doing them over the period of months, one would need a mammoth amount of propellant.
- I can't see what purpose it would serve.
So, to me it looks like they are either changing by themselves or the orbital data itself is wrong. I suspect the data being wrong as I haven't come across any phenomenon where orbital plane keeps changing and and also rotating by itself with time. It would require strong external disturbances for that to happen by itself and I doubt there are such strong and sustaining disturbances acting on the spacecraft. So, is the data incorrect?
Edit: I checked data for two more spacecrafts on the same website and they also seem to be behaving similarly. This is either something I don't know of, or the data is garbage.