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The Strangest Moon In the Solar System
StartsWithABang writes Moons in our Solar System — at least the ones that formed along with the planets — all revolve counterclockwise around their planetary parents, with roughly uniform surfaces orbiting in the same plane as their other moons and rings. Yet one of Saturn's moon's, Iapetus, is unique, with a giant equatorial ridge, an orbital plane that doesn't line up, and one half that's five times brighter than the other. While the first two are still mysteries, the last one has finally been solved.
Linking to Medium is the new linking to LiveJournal.
It's HUGE.
Watch this Heartland Institute video
Yet one of Saturn's moon's, Iapetus, is unique
Aren't they all unique?
"Total destruction the only solution" - Bob Marley
Viewed from which side? Counterclockwise does not apply here.
Viewed when looking down from the north pole. This is mentioned in TFA, per
Rather that [sic] (looking down from the north pole) orbiting counterclockwise around its parent planet, which all the other moons do, Phoebe revolves clockwise around Saturn.
I found this article to be rather long winded in order to create a story with suspense.
The moon has a side facing away from Saturn which is darker then the side facing saturn. It seems to be due to collecting dust from a larger ring that is on the border of its orbit.
Done, saved you a long and pointless naritive.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
The fun is that in 2001, the bright side of Iapetus was sculpted, with the monolith in the middle. In reality the dark side is sculpted from passage through the dust ring.
The living have better things to do than to continue hating the dead.
We aren't all using tablets or phones. Looks like crap on my laptop.
As for the article, if you are going to casually use words like "sublimate" without definition, it means your target audience is sophisticated enough that you don't need to write using a breathless, made for reality TV, annoyingly *excited* tone.
POssibly the moon is formed from 2 bodies colliding and before it could completely settle down into a round shape it froze with that ridge remaining?
The only planet whose north pole is not on the same side of the Ecliptic as the Earth's north pole is Uranus. In Uranus' case, the north pole is nearly in the Ecliptic itself, tilted at 98. All the other planets have their rotation axis (axial tilt) either nearly vertical to their orbit plane (e.g. Mercury, Venus, Jupiter), or tilted at about 20-30 (Earth, Mars, Saturn, Neptune).
Dude... Do you think that when Pink Floyd sang about the Dark side of the moon, they were really talking about Iapetus?
Yes, agreed for most planets... but what about Uranus?
(serious question, since it rotates sideways on its axis)
The only planet whose north pole is not on the same side of the Ecliptic as the Earth's north pole is Uranus.
Venus's axial tilt is 177 degrees, that's about "not on the same side of the Ecliptic" as it could be.
Do what thou wilt shall be the whole of the Law
I was going to say that since all planets (and most moons) with the exception of Uranus have their rotational axis all lined approximately the same way as Earth, that the north pole could be defined as the same as earth: the pole from which the planet seems to be rotating counter-clockwise (or anti-clockwise for you Brits).
But there's a glaring exception to that rule: Venus rotates in the opposite direction - clockwise from its "northern" pole. The leading theory is, like Earth, Venus was struck by a large planetoid early in the solar system's history, but unlike Earth's moon, the planetoid was totally absorbed by Venus, i.e., a direct hit. The angular momentum imparted by the planetoid caused Venus to "flip". The same theory has been proposed for Uranus' sideways orientation as well.
"A little misunderstanding? Galileo and the Pope had a little misunderstanding."
They promise to only look at our metadata, not the content of our cell calls and digital pictures.
Or just use the right hand rule :) Where "north" is by definition the positive direction of the total angular momentum pseudo-vector of the solar system.
According to the IAU definition, the north pole for a major planet (or one of its satellites) is the pole on the same side of the ecliptic as the Earth's north pole, the North Celestial Hemisphere. By this definition, Venus and Uranus are retrograde rotators -- they rotate clockwise about their north poles.
For comets and minor planets (including Dwarf planets), the north pole is the pole about which the body rotates counterclockwise. So the north pole of a retrograde-rotating asteroid points into the South Celestial Hemisphere.
This brings us (as do all topics that mention the IAU) to Pluto. Pluto rotates retrograde. It was once considered a major planet, so it's north pole would have been on the same side of the ecliptic as ours. But as a dwarf planet, the opposite definition applies. Even before the 2006 decision, the convention was inconsistently applied. Papers have been published using each definition of the north pole, and they're not always good about stating which convention they used. With New Horizons on the doorstep, we're going to need consistency for mapping and navigation. So I believe the mission has decided to use the current IAU definition consistently to avoid any confusion. There was a huge fight over the coordinate system of Vesta on the Dawn mission, and we don't want that.
"North" is a geocentric concept that can be projected outward upon the solar system.
That one is simple and easy since there is a clear consensus among Earth dwellers as to which way is north.
In other situations it can get more complicated, such as when projecting the egocentric concept of "Left" and "Right" outward from an individual point of view. The simplest case is when looking at a photo of Mutt and Jeff, and being told that Mutt is on the left. Even though when the photo was taken both Jeff would have said that Mutt was on his right side.
There are even greater problems when there is no consensus within the group. For instance, for a libtard "going to the Left" is definitely right, but "going to the Right" is clearly wrong, which is as succinct a summary of the state of USA politics as you can get. Well, except for the die hard Tea Partiers, where "Right" is always right, and "Left" is always wrong. But then after rejecting everything that is not right, all the Tea Partiers have left is right. Which is at best terribly confusing.
It was all so much simpler during the last American civil war, when everything was either North or South.
Will
Actually that's a mistranslation, it should be:
They promise to only look at our metadata, not the content of our glial cells and mental pictures.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
In one of the books on the Making of 2001 Kubrick it was hard to obtain the F/X artisitc effect he wanted of Saturn and Iapetus, so he switched to a black-gate orbiting Jupiter. The movie and the book were co-made at the same time, mostly agreeing. Jupiter is one choice because its the second largest thing in the Solar System. Clark instread, chose something so odd, that could not be natural.
Towards Polaris, and in fact that gives the direction of "galactic north" too. Note due to precession of Earth's axis after 3000 AD Gamma Cephei will become the pole star, and Iota Cephei in 5200 AD. Thuban was the pole star in 3000 B.C. Polaris will again become the pole star about 27,800AD