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Saturn's New Moons Named
sebFlyte writes "The BBC is reporting that three new moons found orbiting Saturn at the end of last year have been named. 'Two moons detected in August have been given the names Methone and Pallene, while another found in October has been provisionally named Polydeuces.' Polydeuces is also reported as being a very strange object-- a trojan moon. It sits in a spot near a larger moon where the gravitational pull of the other moon (Dione here) and the planet cancel each other out."
Polydeuce bigalow.
Planet Gigolo
That's no Trojan moon...
I hadn't ever really thought about Lagrange points before I read that article. They are both interesting and intuitive to me. That there is a spot between two gravitational bodies that creates a "dead" spot, around which an object can orbit in a tug of war. Neat stuff. I find that more interesting than what names they have chosen for the moons.
We are one consciousness experiencing itself subjectively. Back to you with the weather, Bob!
...Zero G manufacturing?
Yikes better update my anti-virus. Don't want to get infected by W32.Polydeuces.A@mm now.
News Reporters Make Tasty Polar Bear Treats!
....Methone and Pallene, Polydeuce? Where's the cowboy neil option?
There is no replacement for displacement.
How can that possibly be stable? Wouldn't the slightest deviation lead to the moon coming crashing down in either direction?
Almost all the solar bodies have been (in English) named after Greek and Roman gods. Since English is a Germanic lanaguage, why not name some new ones after figures closer to home?
At the bottom of the
Naming them Ronald and Reagan?
I believe the way the Lagrange points work (from what I read) is that the object "in it" orbits the lagrange point by being tugged back and forth... it's not just "sitting there at some fixed distance relative to the 2 bodies.
We are one consciousness experiencing itself subjectively. Back to you with the weather, Bob!
Did you even read the article?
The point between to celestial bodies (usually a planet and it's moon) where the gravity of one is equal to the gravity of the other is called the Lagrange point.
Usually closer to the smaller of the two bodies, this point is a common location of sci-fi space stations, as there is no need to use an orbit to keep the station from decaying back into the larger bodies atmosphere.
There are no gods but ourselves.
I claim Godfather!
The following statement is true
The preceding statement is false
damn i wish i had mod points.. +1 ATHF reference
The best education consists in immunizing people against systematic attempts at education. - Paul Feyerabend
must have been on drugs!
(Dione here)
Me too, cya.
I was a bit surprised about the name Polydeuces, because he (the mythological character) had little to do with Troy. However, it turns out that there's another Trojan moon called Helene (now this makes sense!), and Polydeucues is Helene's brother.
When asked why they had named the moon now after millenia of observation, one student from Saturn's top university said, "Why not, you know? I mean, like, we had named everything else of importance, dude. Even the unimportant places. So like this was all that was left."
No comment could be received from inhabitants of !3kd8dgh, since they don't speak Standard Galactic. Moreover, they laughably think they are the only inhabitanted planet in the system, and it's considered taboo to disabuse them of this ignorance.
Named by whom?
Oh Saturn, I love your rings. They make you look so beautiful. I just love being around them for all this time.
...TROJAN MOON.
Oh moon, the way you circle around me makes my weather patterns get all disrupted. You are just the perfect little moon, I love you.
Oh Saturn, I think its time for some gravitational pull...
This post has been filtered for sanity.
I would have chosen the IBM Stellar Sphere
The Wikipedia article, a nice summary by mathematician John Baez, and another summary and a proof of L4/L5 stability (PDF) by astrophysicist Neil Cornish.
In celestial mechanics, Lagrange points come up in the three-body problem, where you have two large bodies (eg Sun and planet, planet and large moon) and one small object (a Trojan asteroid, spacecraft, new Saturn moon).
Lagrange points are the five places relative to the two large objects, where the third object will be held at the same position - relative to those two objects - in its orbit. In other words, there will be a net force on the third object that will result in it accelerating around the largest object at the same rate as the second largest object.*
A Lagrange point is stable if an object near by the L point will tend to be pulled towards or orbit around that point if it's a bit off the exact point. The L point is unstable if the object tends to be pulled further away from it once it wanders a little away.
The L1 point (in between the two large bodies), L4 and L5 points (60 deg ahead and behind the orbiting large body) are stable, the L2 and L3 points are unstable. Many of our solar observing spacecraft get sent to orbit the L1 point.
*(Center of mass discussion left out for relative simplicity)
We can see lightyears and lightyears away with Hubble, and other large telescopes. So how is it were still finding moons in the solar system?
Thanks for the info.
And all this time I thought the ZZ Top song was titled after a city in Texas...
Didn't take long for the domain name scavengers to pick up these names. I managed to snap up methone.com. The easiest to remember in my opinion.
Apparently not many people paid attention to this in high school.
The title of this article should be: Saturn's New Satellites Named.
Unique.
You may find explanations of this here. Theoretically, the object does orbit at a fixed distance relative to the two bodies -- forming a rotating equilateral triangle them, in fact, for the case of the stable L4/L5 points -- although in reality, a small perturbation will cause the object to be "tugged back and forth" in little wobbles around that rotating equilateral point.
Some spacecrafts are in orbits around L1 and L2 point of the earth-sun system, but those orbits are only semi-stable. The spacecrafts use some of their fuel to stay in those orbits longer than they would without propulsion, but eventually they will drift out of their orbits.
One can calculate a gravitational-rotational pseudopotential for the system (see e. g. here). In this pseudopotential, L1, L2 and L3 are saddle points (pseudopotential increases along one axis in both directions and decreases along another axis in both directions), L4 and L5 are maxima - one would expect that a body would move away from them. But the potential cannot include forces which depend on velocity and not on position - in our case the coriolis force - therefore it's called pseudopotential. Coriolis force causes an object to orbit the L4 or L5 point in a complicated path. If the object has more kinetic energy it can get from L4 to L5 via L3 and back again - this is called a horseshoe orbit.
Who decides on the names of these moons?
It's Luna. Lunar, Lunacy, etc are all related to it.
" Well, we've named all the planets in THIS system after greek mythological characters."
Jupiter, Mars, Venus, etc, are all Roman names. Greek names would've been Zeus, Aries, Aphrodite...
Life is hard, and the world is cruel
http://en.wikipedia.org/wiki/Moon_(disambiguation) :
The term Moon refers, among other things, to:
1. The Earth's only natural satellite, the Moon.
2. A common term for other natural satellites.
That Polydeuces must be covered with dust and crap that got stuck in the Trojan point no? I mean you've got a big mass *and* a gravitational well strolling through this area full of dust and ice particles, maybe it's like the way they thought our moon might be - covered with dust so thick you could sink right into it! Maybe the whole thing's electrically charged? You could fuel a whole lot of science fiction with this, but I'd like to find out more of the real side of the moon before the sf authors have time to dream anything up.
Telesto and Calypso share an orbit with Tethys. Helene is a Trojan in Dione's other coorbital Lagrange position.
Constitutionally Correct
I thought it said "Satan's New Moons Named". I never knew the prince of darkness was so massive.
As far as I can see from the article and from the IAU website, the International Astronomical Union hasn't approved these names. By common agreement in the astronomical community, they have the final word on approving names. So until they meet and approve this, all that is being reported is that the Cassini team is *suggesting* names for the moons *to* the IAU. The IAU has the right to shoot down their suggestins. (I'm a bit skeptical of Polydeuces being accepted since it doesn't fit the usual scheme. But what do I know?)
Whoa. Lowest-rated post for a(n arguably uninteresting) reference to the story's "dept."? *shrug*
They're still angling to rename one of the planets after him.
yeaaah nice name, really origional.... it doesnt matter what its called really.. its just the same as the others.
Geez, what's it going to take ?
For some reason these names are starting to remind me of the names of worlds in Populous.
Scoqazpert
Methone
Bileapert
Pallene
Not that different, really.
IMESHO (yes, you're on /.) ad hominem falls under the debating equivalent of "violence is the last refuge of the incompetent".
Mr dj42 hardly even rates on the pomposity scale compared to many others here. To me he sounded kind of whimsical rather than elitist.
Lagrange points might have been carefully designed to enable random cool stuff to happen in scifi stories.
Got time? Spend some of it coding or testing
Definite points for classically understated dry humour there.
Got time? Spend some of it coding or testing
Planet Bilious, named after the Oh God of Wine (the antithesis of Bacchus - or Dionysus, depending on your preference for mythologies). Planet Verucca, named after the Verucca Gnome. Planets Death, Pestilence and so on, after the Four Motorcyclists. Planet Hogfather, after the Discworld's pig-propelled sleigh driver. The Soul Cake Duck asteroid belt, with asteroids named after cakes - "Welcome to the Pavlova Uranium Extraction Facility!" - or ducks - "We will be landing at Daffy Station in five minutes, please seal your pressure suits and check your safety webbing". Planet Violet, after the tooth fairy of the same name (or possibly Bob and Helen Parr's daughter, but let's not open that film-can of worms).
Got time? Spend some of it coding or testing
...or Barbara and Laura?
Got time? Spend some of it coding or testing
<whock!> Right! Sure sorted that argument out...
Got time? Spend some of it coding or testing
Trojan moons are nothing new. Telesto and Calypso were discovered more than twenty years ago...... a new trojan moon isn't really news anymore...