Starship Asterisk*

A Long Storm System on Saturn

Explanation: It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the above cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet. The storm was tracked not only from Earth but from up close by the robotic Cassini spacecraft currently orbiting Saturn. Pictured here in false colored infrared in February, orange colors indicate clouds deep in the atmosphere, while light colors highlight clouds higher up. The rings of Saturn are seen nearly edge-on as the thin blue horizontal line. The warped dark bands are the shadows of the rings cast onto the cloud tops by the Sun to the upper left. A source of radio noise from lightning, the intense storm was thought to relate to seasonal changes when spring emerges in the north of Saturn. After raging for over six months, the iconic storm circled the entire planet and then tried to absorb its own tail -- which surprisingly caused it to fade away.

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Uh, isn't the Cassini spacecraft kaput?

Scabulus wrote: ↑Sun Sep 15, 2019 4:15 am Uh, isn't the Cassini spacecraft kaput?

It wasn't in April 2013 when this APOD originally ran. (Sunday's are repeats.)

Jupiter seems to have a similar storm pattern. How does it compare with Saturn's?

Weird storm... came around... bit itself... then quit... how can we get a hurricane to do that? Oh, yeah, this one went around the whole planet....yyyeeaaahhhh.... not a good idea here....

:---[===] ^

Larger than a Category 5!

Scabulus wrote: ↑Sun Sep 15, 2019 4:15 am Uh, isn't the Cassini spacecraft kaput?

Yes. The word "currently" has now been changed to "then" in the text on the main NASA APOD. I apologize for the oversight.
- RJN

How do they know that the storm "tried to absorb its own tail -- which surprisingly caused it to fade away."?
And it's being compared to a snake. I don't think snakeopomorphizing the storm is the best idea.

What velocity was the storm's wind? Any way to calculate that?

Thanks,

Ronn

I am kind of confused by the line, 'largest and longest lived storm ever recorded in our solar system. Maybe they mean largest and longest storm stretching all around the planet. As for longest lived, isn't that the Great Red Spot which supposedly was seen by Galileo hundreds of years ago? I mean if this storm was only first seen in 2010 how do they know it is hundreds of years old? Did Galileo mention seeing that? And if it was so old why didn't anybody see it in the year 2001, or even in the year 1981 when Voyager passed by Saturn?

De58te wrote: ↑Sun Sep 15, 2019 3:33 pm I am kind of confused by the line, 'largest and longest lived storm ever recorded in our solar system. Maybe they mean largest and longest storm stretching all around the planet. As for longest lived, isn't that the Great Red Spot which supposedly was seen by Galileo hundreds of years ago? I mean if this storm was only first seen in 2010 how do they know it is hundreds of years old? Did Galileo mention seeing that? And if it was so old why didn't anybody see it in the year 2001, or even in the year 1981 when Voyager passed by Saturn?

Well, you left out the opening modifier in the description: "one of the ..." which totally changes the meaning and immediately answers your questions.

Ronn M wrote: ↑Sun Sep 15, 2019 3:26 pm
What velocity was the storm's wind?

• Up to 200 m/s (Category 5 hurricanes include anything 70 m/s or more):

https://www.nasa.gov/mission_pages/cassini/multimedia/pia16722.html wrote:

Saturn storm data obtained on Jan. 11, 2011.

---

This image from NASA's Cassini spacecraft reveals the wind patterns within a large vortex that was spawned by a giant northern storm on Saturn. The arrows indicate the local direction of the winds. The vortex, a clockwise-spinning swirl, was spun off from the head of this storm in early December 2010, shortly after the storm erupted. The bright head of the storm moved swiftly in a westward direction around the planet, while this vortex drifted more slowly.

So is that black spot toward the lower left the shadow of a moon?

johnnydeep wrote: ↑Sun Jul 24, 2022 2:09 pm So is that black spot toward the lower left the shadow of a moon?

Probably some shadow like illustrated on the Cassini Imaging Team link.

johnnydeep wrote: ↑Sun Jul 24, 2022 2:09 pm So is that black spot toward the lower left the shadow of a moon?

Pictured here

"The shadow of the moon Enceladus is visible on the planet in the lower left of the image."

bystander wrote: ↑Mon Jul 25, 2022 3:27 am

johnnydeep wrote: ↑Sun Jul 24, 2022 2:09 pm So is that black spot toward the lower left the shadow of a moon?

Pictured here

"The shadow of the moon Enceladus is visible on the planet in the lower left of the image."

Aha, thanks! I sometimes fail to fully read all the linked-to pages and missed that one.