View Full Version : Uranus' axial tilt

2003-Dec-25, 07:25 AM
Hi again,

I have a query that I have been thinking about for a little while, what theories are there for the massive axial tilt of Uranus? and what is the story behind its moon Miranda (did i get that right?)

2003-Dec-25, 07:59 AM
There is a lot of theory about Uranus..

This is the newest theory : Some Scientist says Uranus and Neptune came to exist at the very edges of the solar system.
http://abcnews.go.com/sections/scitech/Dai...nets991208.html (http://abcnews.go.com/sections/scitech/DailyNews/planets991208.html)

This is the oldest one : An early siting of Uranus theory
http://www.btinternet.com/~prgreetham/Wise...en/theory5.html (http://www.btinternet.com/~prgreetham/Wisemen/theory5.html)

:lol: Miranda :)

The eleventh of Uranus' moons is the world Miranda. Miranda is a very interesting world. It is made up half of rocky material, and half of ice. In one place Miranda has a huge cliff that is 5 km high. Miranda was discovered in 1948 by Kuiper.

This icy world was named after a daughter of the magician Prospero in Shakespeare's The Tempest.

If u need information of those moon please visit
one of my favor site :P

2003-Dec-25, 09:09 AM
could you please elaborate on the theories, well at least where they are

2003-Dec-29, 10:36 AM
Littlemews please don't copy slabs of text off other sites like that in future. It breaches copyright laws.

2004-Jan-02, 12:53 PM
just supply me with heaps and heaps of links!!!

2004-Jan-02, 11:12 PM
Nice links littlemews but they don't address the questions...

I don't know what the latest theory is, but I did hear that Uranus was thought to have been struck by a comet sized object that knocked the planet onto it's side - it's also thought that this caused the destruction of several of it's moons, thereby forming the rings.

Miranda could also have been caught up in the mayhem. One theory is that the moon originally had a rocky interior and an icy exterior but that it was fragmented into icy and rocky chunks after a collision with another body. Those chunks remained in the same orbit and over time regrouped and reformed the shattered moon, thereby giving rise to the strange randomly ice / rock moon we know today.

2004-Jan-02, 11:30 PM
I think a massive comet, or asteroid (even maybe a rogue planet) hit Uranus.

2004-Jan-03, 12:18 AM
I have no idea what caused Uranus's axial tilt, but I'm pretty confident that it wasn't a collision with a comet or anything else. It has to go right back to the formation of the planet itself, because whatever did it also affected all it's natural moons.

Uranus has 26 known moons (and counting). The outer 8 are all over 4 million km from the planet, are small, move in retrograde orbits that are highly inclined (i.e. 140-170 degrees), and quite elliptical, all of which indicates that they are captured asteroids (or KBOs, or Centaurs), so we can ignore them. The inner 18 are all within .5 million km of the planet, are of varying sizes, but are all in almost perfectly circular orbits that are right on Uranus's equator. Every single one of them has less inclination to Uranus's equator than our moon does to ours, and a less eccentric orbit than our moon has. They undoubtedly were formed at the same time as Uranus.

A collision with a comet (or any other object) certainly could not have shifted Uranus's tilt by 98 degrees or so and at the same time shifted the inclinations of 18 satelites, not to mention a ring system, by exactly the same amount. In fact, it is very difficult to conceive of any mechanism that could manage that trick. So the spin of the proto-Uranus must have already been tilted 98 degrees as the planet was forming.

2004-Jan-03, 07:50 AM
how can this be? what possibly caused it in the first place?

2004-Jan-03, 12:16 PM
This looks more and more like the intro to the tv-series Third Rock from the Sun!
Don't be surprised that what you saw there will become our new Standard Model of the Planets.
Rock 'n Roll!!

2004-Jan-04, 02:44 AM
that is an interesting point! has that theory and the like being explored yet?