Monster Hurricanes On Saturn

[Saul Trabal]

Here's the link:

http://saturn.jpl.nasa.gov/news/press-release-details.cfm?newsID=876

There are two huge hurricane-like storms at the north and south poles of Saturn, with winds of 300 mph in each storm. The storms have dozens upon dozens of towering cumulus clouds, which are the tops of gargantuan, savage thunderstorms underneath.

I think Saturn has more violent thunderstorms than Jupiter does-and Jupiter's thunderstorms are pretty savage in their own right. Amazing stuff. Now, if we could only photograph lightning on Saturn. It's much harder to do that due to Saturn's haze and ringshine.

You've GOT to check out the photos. It is actually frightening how violent it all looks. Simply amazing stuff.

 

[Chip Redmond]

Those are some pretty awesome photos. Its amazing how the storms fuel themselves and stay completely stationary over the poles. I imagine some of the stationary reasoning and perhaps the hexagonal features are because of the magnetic field of the planet. Though the field is stronger than the Earths by a massive amount it is smaller than Jupiter's. The magnetic field is, correct me if I am wrong, completely symmetric isn't it? I am pretty sure that it is, and that may prevent the strong pressures at the poles from moving. Just some thought.

Chip

 

[Saul Trabal]

Those are some pretty awesome photos. Its amazing how the storms fuel themselves and stay completely stationary over the poles. I imagine some of the stationary reasoning and perhaps the hexagonal features are because of the magnetic field of the planet. Though the field is stronger than the Earths by a massive amount it is smaller than Jupiter's. The magnetic field is, correct me if I am wrong, completely symmetric isn't it? I am pretty sure that it is, and that may prevent the strong pressures at the poles from moving. Just some thought.

Chip

One thing I've thought about, in terms of photographing lightning flashes...there would still be a problem with the haze, but at the north pole of Saturn, it's still immersed in darkness. Of course, they may be similar to terrestrial hurricanes in that there may be little lightning in them-but I might be completely off base there.

The "eye" of the southern storm is 5,000 miles across, and I think the "eye" of the northern storm is similar. Why the poles, though-and why are the storms locked there?

I'm not sure about the magnetic field, or how the liquid hydrogen ocean below the clouds (which makes up most of the planet) affects it. One thing for sure, though-the heat from this ocean is thousands of degrees, which is what's creating such severe weather.

Some other Saturn facts-

Saturn's winds can reach 1,000 mph.

Lightning in Saturn's clouds has ranged from 1,000 to 1 million times more powerful than Earth's. There's currently a huge thundercloud in Saturn's southern hemisphere that has lightning 10,000 times more powerful than Earth's.

It would be cool if a 3-d computer representation could be done of both mega-hurricanes and that thunderstorm I just mentioned-which is half the size of the Earth.

What's scary is the close-up of the eye in Saturn's southern storm-seeing thunderclouds floating within, and MUCH bigger, darker clouds barely noticeable below them. It's like being in a giant arena of thunderstorms-an arena larger than the United States!!

 

[Simon Andersen]

Thanks for the link, amazing images. Keep posting stuff like this, I never get to it by myself unfortunatly.

 

[Adam Lucio]

Wow thats amazing.

Im pretty sure Saturn doesnt have a surface so by definition there could be no tornadoes, but could you imagine if somehow something similar were to form. 10 mile wide wedge anyone?

Those pictures were so interesting to see. Saturn was always my favorite planet. When I was a kid I asked for a telescope for christmas and I told my parents that if it wasnt able to see the rings I didnt want it.

 

[Laura Duchesne]

Yikes.

This hexagon is populated by fast-moving clouds which also reach speeds of over 500 kilometers per hour (300 miles per hour).

Are there any theories on WHY that one storm is a hexagon shape? I didn't think anything like that would be possible?

 

[Derek Mohr]

Are there any theories on WHY that one storm is a hexagon shape? I didn't think anything like that would be possible?

I agree, and do these storms not have any squall lines venturing away? Sigh, earth has a complicated enough climate, trying to learn another planet would be no small project! Lol.

 

[Saul Trabal]

Wow thats amazing.

Im pretty sure Saturn doesnt have a surface so by definition there could be no tornadoes, but could you imagine if somehow something similar were to form. 10 mile wide wedge anyone?

Those pictures were so interesting to see. Saturn was always my favorite planet. When I was a kid I asked for a telescope for christmas and I told my parents that if it wasnt able to see the rings I didnt want it.

The theory is that planets like Jupiter and Saturn don't have a surface (not sure about Uranus and Neptune)-the air just gets denser and more liquid until it eventually changes into the liquid hydrogen ocean. My guess is that-if an object could survive the fall through the clouds, it would slow down and stop in the liquid hydrogen goo. At the transition point, the air pressure is thousands of earth atmospheres, and the temperature is probably 5,000-6,000 degrees. There's little wonder the weather is so ferocious on the gas giants, given the fiery heat from below. The difference with Uranus and Neptune may be that they have oceans of superheated water, with the air pressure at the transition point again being thousands of atmospheres, with the temperature being thousands of degrees.

Keep in mind the following-the Galileo spacecraft dropped a probe into Jupiter, and the probe had a hull of titanium. Titanium, as I understand it, melts @ 3,100 degrees Fahrenheit. It's most likely that the titanium hull evaporated into gas. The entire probe was vaporized.

 

[Saul Trabal]

I agree, and do these storms not have any squall lines venturing away? Sigh, earth has a complicated enough climate, trying to learn another planet would be no small project! Lol.

A single thunderstorm on Saturn can be the size of the U.S. So, go figure how big a squall line could be!!!!!!

 

[Derek Mohr]

A single thunderstorm on Saturn can be the size of the U.S. So, go figure how big a squall line could be!!!!!!

Sounds like a chasers dream to me

 

[Saul Trabal]

Sounds like a chasers dream to me

...or nightmare. Getting too close to those beasts could mean certain death!

 

[rdale]

Certain death? Or definite death?

 

[cdcollura]

Good day all,

This is a very interesting thread, as well as the pictures on the JPL / NASA sites.

The large "hurricanes" on Saturn are essentially "polar vortexes", and like the (much weaker) ones that cause polar easterlies on earth (low pressure aloft over high pressure at surface), they are "locked" at the poles.

Often, planets with a gas atmosphere, even the thick one on Venus, rotate faster than the planet rotates (like a jet stream, but larger) ... For example, Venus rotates every 225 days or so (don't quote me on this), but it's upper atmosphere rotates every 4 days (this is called super-rotation) and is also found on Jupiter, which - despite it's immense size - rotates once in an impressive 10 hours. Saturn's is just under 11.

With the Gas Giant planets (Jupiter, Saturn, etc), the immense speed of rotation at the equator is at it's "virtual surface" (cloud deck / 1000 MB height). These planets have no solid "surface", just increasing density (until liquid density is achieved) as one procedes deeper into the atmosphere. The centrifugal effect of this rotation is so great, it makes Saturn visually "flattened" at it's poles.

On a "solid" planet, like earth, the rotational speed decreases from the equator when one moves towards the poles as a Cosine function of the lattitude angle (half the speed of at the equator at 60 deg north / south lattitudes).

With a gas giant, there is a high probability that not all layers of the atmosphere rotate at the same rates (such as with super-rotation). The massive polar vortex on Saturn can be attributed to the strong winds adjacent to lighter winds (and less rotation) at the poles, probably above slower moving (or faster moving) winds.

The "coriolis" force, as it is on earth as when an air parcel changes lattitude and is affected by the rotation speed, will be MANY times stronger on a rapidly-rotating gas giant. Jupiter's big red spot is proof of this. Similar storms appear on Saturn but are shrowded (in contrast) by the haze.

Convergence, mixing, and convection attrinute the the small (small being thousands of miles across by Earth standards) cloud formations within the vortex. The "hexagon" shape can be attributed to small waves / sub-vortices within the eye wall of the vortex (like those found in polygonal eyes of hurricanes here on earth).

Everything on these planets is BIGGER, including the lightning (as Saul mentioned). Yes, there will be tornadoes and such ... However, they cannot be true tornadoes as there is no "surface" to touch down on - So I guess I'll call them funnels (just big ones).

Thunderstorms on such planets will also behave like their much smaller counterparts similar to elevated storms we see in the western US on Earth. There is no surface for parcels entering them to work with. No gust fronts either, unless an iscentropic / density surface is encountered to falling air (or in this case, gas) parcels. This should explain the lack of outflow boundaries / squall lines (no cold pool to spread out along the "ground").

Lightning on such planetary scales would be hundreds or even tens of thousands of miles long, and entirely cloud-to-cloud as "dendrite" / anvil crawlers. Anything struck by such lightning will face certain vaporization.

Another consideration is the composition of what is actually doing the "phase change" to release latent heat (that is being transported from lower layers of the atmosphere). Water vapor provides the transfer on earth to drive storms ... On the Gas Giants, Ammonium ice, Methane, Hydrogen, etc play these roles (along with a trace of water).

Intense radiation influx is also another consideration. Jupiters magnetic field is so strong that is focuses charged solar particles - even at such a great distance from the sun - So much that an up-protected astronaut will be killed from radiation sickness in minutes. The correlation of solar radiation and lightning has a mixed debate here on earth, let alone it affecting a Jovian / Gas Giant planet - Just another thing to consider.

My 2 cents worth...

 

[Saul Trabal]

Only got time for one quick thought-

What about sprites? Can you imagine how big they must be on Saturn (and Jupiter)??

Edited to add: interesting points, cdcollura; I'll address them later, when I have time.