Quote:
|
Originally Posted by Jerry
Supernova 1987A exploded recently.
|
Non sequitor. Was this supposed to mean something?
Quote:
|
Do you have a plausible answer? Nasa had a half dozen different explanations for the behavior of Galileo's wheels, which one is more plausable? Dark Matter, inflation, Dark energy, time dilation - all magic.
|
We're not talking about Galileo, were talking about Cassini. Why are you bringing up any of this? These other theories have no bearing on Cassini other than you don't like them. The difference between these theories and your musings is that they actually have some evidence to back them up.
Quote:
Actually, what I am hoping is the other way around: The behavior of the reaction wheels, if I were privy to the details, could better constrain the theory. I don't know if the wheels are using more power or less, or if there is a conflict as to the momentum expected in the wheel. Here are things that could be happening:
1) The wheel tracking roll, is recording more roll than expected - this could be true if the gravitational effects of the moon are tugging with a greater force than calculated, so the wheel gets in a tug-a-war with the other parts of the guidence system.
2) There could be certain resonant velocities in the wheels - any of the wheels - that interacts with one of the nature frequencies of Saturn - this would be the interference wave nodes involving both Saturn and her moons.
3) A true violation of the weak equivalence principle - the electrical force necessary to drive the wheel is greater or less than expected, screwing up the hysterises dampening parameters.
4) Something else.
I have always favored door 1), but this last episode sounds more like door 3), - effecting multiple types of stepper motors.
|
Lots of flailing, but you've yet to show how any of this could effect one wheel and not the rest.
Quote:
|
Don't you think it is odd that when both Galileo and Huygens were close to Jupiter and Saturn, reaction wheels have behaved curiously?
|
No. Balky reaction wheels are part of the space game. Take a look at the problems Hubble and the ISS have had. Your reading too much into this.