15. Messier Tidy Upper Says:
May 7th, 2010 at 6:31 am
@ ^ Just me :
but I assume that the rotational period is not determined by the cloud movements, right? Any thoughts?
I’m not sure & I could well be wrong – please correct me if I am – but I think cloud patterns *are* actually used along with perhaps magnetic fields to judge the gas giants rotation periods.
Its a good question and pretty hard to work out given these planets are gas and fluid rather than solid bodies.
I vaguely recall reading somewhere that Saturn’s rotation period has actually changed between the time Voyager II last flew past the planet in 1980-83 ish (?) to when Cassini arrived in 2004 ~ish (?) – although maybe it was just a case of a more precise measurement being made. I’ll have to research this further myself now.
You might try asking this question on the BAUT forum too :
if you haven’t done so already.
Otherwise, if anybody can explain or elaborate further on this it’d be great.