Recently, I've been learning astronomy for self-study. And here is something I couldn't understand:
The spin rate of Jupiter differs by latitude. The spin rate at high latitude lags the one at low latitude for 5 mins.
Could anyone help to explain it? Thanks so much!
Re: [Help] about the spin rate of Jupiter
Posted: Wed Jan 30, 2013 5:32 am
by neufer
Click to play embedded YouTube video.
faith wrote:
Recently, I've been learning astronomy for self-study. And here is something I couldn't understand:
The spin rate of Jupiter differs by latitude. The spin rate at high latitude lags the one at low latitude for 5 mins.
Could anyone help to explain it? Thanks so much!
Jupiter is a gaseous ball made up of many different wind bands which circle to planet at different speeds.
Re: [Help] about the spin rate of Jupiter
Posted: Wed Jan 30, 2013 9:25 am
by faith
Thanks for your kindly reply.
So, you mean that it is the different composation of wind bands that causes the different speeds? Materials with higher density may have a lower speed?
PS: Although I really appreciate it that you attached a vedio here, I'm still very sorry to say that vedios from Youtube are not available in Internet from China~ So, I couldn't see the vedio you provided.
Re: [Help] about the spin rate of Jupiter
Posted: Wed Jan 30, 2013 9:55 pm
by neufer
faith wrote:Thanks for your kindly reply.
So, you mean that it is the different composition of wind bands that causes the different speeds?
Materials with higher density may have a lower speed?
Density & speed have a more complex relationship.
The wind bands are simply zonal jet streams of different colored
clouds which circulate around the planet at different rates.
<<Jupiter is perpetually covered with clouds composed of ammonia crystals and possibly ammonium hydrosulfide. The clouds are located in the tropopause and are arranged into bands of different latitudes, known as tropical regions. These are sub-divided into lighter-hued zones and darker belts. The interactions of these conflicting circulation patterns cause storms and turbulence. Wind speeds of 100 m/s are common in zonal jets. The zones have been observed to vary in width, color and intensity from year to year, but they have remained sufficiently stable for astronomers to give them identifying designations.
The cloud layer is only about 50 km deep, and consists of at least two decks of clouds: a thick lower deck and a thin clearer region. There may also be a thin layer of water clouds underlying the ammonia layer, as evidenced by flashes of lightning detected in the atmosphere of Jupiter. This is caused by water's polarity, which makes it capable of creating the charge separation needed to produce lightning. These electrical discharges can be up to a thousand times as powerful as lightning on the Earth. The water clouds can form thunderstorms driven by the heat rising from the interior.
The orange and brown coloration in the clouds of Jupiter are caused by upwelling compounds that change color when they are exposed to ultraviolet light from the Sun. The exact makeup remains uncertain, but the substances are believed to be phosphorus, sulfur or possibly hydrocarbons. These colorful compounds, known as chromophores, mix with the warmer, lower deck of clouds. The zones are formed when rising convection cells form crystallizing ammonia that masks out these lower clouds from view.>>
