The north pole of Uranus has a stormy vortex and we've just seen it for the 1st time (photo)

[Admin]

Once thought to be drab and inert, Uranus' atmosphere is gradually revealing how storm-ridden it really is.

The north pole of Uranus has a stormy vortex and we've just seen it for the 1st time (photo) : Read more

 

[jpdemers]

With the planet on its side, how did anybody decide which pole was "North"?

 

[billslugg]

Looking down on the Solar System from above (North) it can be seen that the Sun and all the planets except Uranus rotate counter clockwise. All planets also revolve counter clockwise around the Sun. On Uranus we look for the pole that is rotating counter clockwise and we find that pole tilted 98° to the Solar System. This likely happened because of a collision with another large planet very long ago.

 

[Meteoric Marmot]

Venus also rotates "clockwise" (retrograde).

I find it curious that we acknowledge that Venus rotates retrograde while we say "Uranus orbits the sun tipped over onto its side by 97.8 degrees."

To me it makes more sense to say that Uranus rotates retrograde with an 82.2-degree axial tilt.

Anyone have a good explanation for this or is it "Just because"?

 

[billslugg]

Yes, you are correct, Venus is also retrograde. And yes, Uranus is "retrograde with an 82.2° axial tilt" but Joe Sixpack would not understand that. He can deal with "tipped on its side" though.

 

[jpdemers]

There are two conflicting definitions. One applies a "right-hand rule": if the fingers of your right hand indicate the direction of rotation, your thumb points north. The other is the International Astronomers Union (IAU) convention: the hemisphere of a planet that is mostly above the "invariable plane" (basically, the ecliptic plane) is the "northern" hemisphere. ("Above", by yet another convention, is the side where Earth's northern hemisphere is found.) Saying that Uranus has a "97.8° tilt" puts the (right-hand rule) "north" pole on the southern side of the ecliptic, contravening the IAU convention. (Which apparently does apply to Venus.)
Joe Sixpack couldn't care less, but you'd think astronomers would have come to an agreement.

I see a reference to the "North pole of Europa" in another Space.com article, which makes me look forward to designating the poles of Uranus' moons.

 

[Classical Motion]

There is a right hand rule and a left hand rule. The right hand rule is for "positive" charge and the left hand rule is for "negative" charge. Electrical charge is not positive and negative, it is left handed and right handed.

This handedness gives charge an asymmetric state. The right handed charge resides in a charged state, and the left handed charge resides in discharged state. Once in a while these states can be temporarily inverted........giving science the mystery of anti-matter.

 

[Atilla De Bum]

Venus also rotates "clockwise" (retrograde).

I find it curious that we acknowledge that Venus rotates retrograde while we say "Uranus orbits the sun tipped over onto its side by 97.8 degrees."

To me it makes more sense to say that Uranus rotates retrograde with an 82.2-degree axial tilt.

Anyone have a good explanation for this or is it "Just because"?

Uranus must be a Captured planet, already rotating from its initial orbit around a sun that went supernova and kicked it loose.

 

[Atilla De Bum]

Sun spot activity has hit Uranus with a large CME, causing the effects we see now.

 

[Classical Motion]

How dense, would a CME be?............by the time it reached Uranus?