Cassini Confirms New Moon of Saturn

pipcorona writes ""In a spectacular kick-off to its first season of prime ring viewing, which began last month, the Cassini spacecraft has confirmed earlier suspicions of an unseen moon hidden in a gap in Saturn's outer A ring. A new image and movie show the new moon and the waves it raises in the surrounding ring material."

"Name That Moon" Contest

From TFA:

The new body has been provisionally named S/2005 S1.

Well, that just rolls off the tongue, doesn't it?

Looks like it's up to us...please post your suggestions for the new moon's name below.

Re:"Name That Moon" Contest

S/2005 S1, as you know, was the Roman god of awkward names.

Re:"Name That Moon" Contest

I don't know, it's all Greek to me.

Re:"Name That Moon" Contest

That's no moon...

Re:"Name That Moon" Contest

Britannia.

Why, after all, it rules the waves in Saturn's belt. Britannia rule the waves. Get it?

Besides, what more fitting tribute to the decline of the British Empire than naming an insignificant 7 kilometer wide hunk of rock(or whatever it's made of) after it. :-)

Re:"Name That Moon" Contest

Ok so consensus would have us leaning toward a really cool name like "Deathstar". Sorry for stating the obvious!

Sphere of Fear

Planet Death?
The Killing Ball?
Death Moon?
Giant Hurt Ball?
The Deathdicle?

Re:"Name That Moon" Contest

goatse

I'm sorry. We can't name it Goatse. I think that award should be reserved for the Goatse Stellar Nursery (A.K.A. NGC 604) [nasa.gov].

You can't tell me that doesn't look like goatse. I swear! It does!

Re:"Name That Moon" Contest

No good. That name would be for a moon of Jupiter (as they're usually named for his various lovers). Saturnian moons are named for Titans or Titan-like gods from other pantheons.

What's so special about a new moon?

I mean, really? Every time they find a new one, the things just keep getting smaller. What's next, a piece of ejecta from another moon the size and shape of a '74 Chevy Impala? Might as well start naming the debris in the rings.

Re:What's so special about a new moon?

The impala is not recognised as a unit of measure. Please use Volkswagons, or ISO Standard Bathtubs.

I'm not sure where the exact cutoff is. I'd assume anything in the decivolkswagon range would simply be considered as flotsam unworthy of a name, unless somebody wants to try to catalogue everything in the rings! You'd need a lot of mountain dew.

Test for grav. pertubation

I'm repeating myself here (see my post below)...

This satellite is actually interesting since it may hold a key on how to retain a gap in the A-ring. It has to do with this small body of a satellite perturbing the neighboring, smaller dusts and removing them from the region effectively.

Somelike that can be studied numerically (n-body problems) to prove the ring's composition, etc. A nice test case for n-body problem.

[I really should be moderating today but...oh well.]

So everythings a moon now?

7km across? Compared to Saturn thats tiny. Thats like saying the ISS is a moon.

So how do you draw a distinction between a moon, a natural satellite, asteroids and space junk? You can either say the moon Earth has an asteroid orbiting it... or that Earth has many moons orbiting it, only one of which is large enough to see.

So if I pay the Russian space program to launch my 1kg rock in lower orbit, do I get to name my moon, or will they just name it
S/2005 SR26GC3.14159265357?

Which makes me wonder, have we named or numbered our own moon yet? Can I call shotgun and call it 'fp!'?

Re:So everythings a moon now?

I do believe our own moon is named Luna, which would be where you get the word "Lunar", although you rarely ever hear anybody call the moon by its actual name.

Re:So everythings a moon now?

Well, at least in Spanish-speaking countries we always call it Luna.

Re:So everythings a moon now?

Actually, in all Romance Languages (those derived by latin), the Earth's moon is called something like "Luna".

• Italian: Luna
• French: Lune
• Spanish: Luna
• Portuguese: Lua
• Romanian: Luna

Re:So everythings a moon now?

I'd usually agree with your sentiment. But this finding is rather important and scientifically useful (for some, not really for me).

The significant thing is this: this moon, how small it is, may regulate the way a gap in the A-ring evolves (or stay clear of smaller rocks),

The effect of the moon's gravity is small, but not small enough to be ignored by the material nearby. Some smart guys can run some numerical analysis to study what the rings are made of, and how a single massive (relatively) body can perturb its surrounding smaller particles.

Re:So everythings a moon now?

Thats like saying the ISS is a moon.

That's not a moon. It's a space station.

Roche limit?

I'm no astronomer, but I remember hearing in Astronomy class about the Roche Limit, the absolute minimum distance that an orbiting body can be from a planet before it'd be disintegrated by the gravity. I also remember hearing that Saturn's rings could have been developed as a result of objects falling within the Roche Limit and disintegrating, thus adding to the ring. This object seems much larger than most of the ones in the ring structure, though. I find that really odd. But then again, IANAA. :P

Re:Roche limit?

The Roche limit only works for large bodies, when you assume that the moon is only held together by its own gravity.

For very small, rocky moons, the tensile strenght of the rock itselv enabls them to exist nearer than the roche limit. Its nothing extremely longtime-stable, but otoh, the tidal forces on a small moon arent very large.

Also, the roche limit is only a contant (2.xxx*R_bigplanet or so) if the bodies have the same density. If the objects is, for example, a captured iron asteroid, its roche limit can be VERY close to a not very dense saturn.

Good use of science money

At least this money is going to find new and useful things. Unlike my state (Kansas) which seems to think that the board of education needs to make us all a laughingstock and put their damn religion in our schools in every science textbook. Why not just require a class, like "Majority religion/philosophy-science indocrination". Look, I learned a LOT from reading Isaac Asimov essays, is there a reason I had to go the the library and check out books of essays from a science fiction author to learn about science? Ya! My state board of education is really badass, getting the job done, and is really cool!

Interesting that...

the waves caused are asymetric, as if the moon is moving faster than the immediately surrounding debris. But thats impossible, because it would move the moon to a higher orbit, or the debris to a lower one, right? Can anyone explain this seemingly wierd phenomenon? Also notice the waves caused on the inner darker ring, what is the cause of that?

Re:Why asymetric?

You nailed it. The ring material inside the S/2005 S1's position is moving faster than the moon, so the waves that the moon excites appear ahead of the moon's present position. (That material just had a close encounter.) The other edge of the gap is orbiting more slowly, so the moon PASSES it, so the waves appear behind the moon.

I'd avoid the word "turning" because it suggests a solid object. The rings are anything but solid.

There are other ways to make asymmetries in these wakes. If the moon isn't well-centered in the gap (although it isn't clear why it wouldn't be) or has a significant orbital eccentricity, you'll get asymmetry as well.

Re:In space no one can see your color?

Imagine being in England for a moment. It's 3 a.m., and you're sitting on one side of the Thames River.

Your friend Bob is perched in his chair on the other side.

Your camera's all set up and ready to snap a picture. Just when you're about to snap, you realize that the nearest streetlight is three miles to Bob's left. Seeing that the Thames isn't a sneeze's distance across, you know that the dinky flash on your camera is pretty useless.

You whip out your trusty imaging spectrometer camera lens and line up the shot with Bob again. Bob's giving off some good x-ray emissions, and those come across just fine.

You could've used a really, really awesome lens and captured a bad photo of Bob--he still reflects some light, though it's a ridiculously small amount--but the IR lens gave you a more descriptive picture of Bob. Why? Mr Bob the Planet Man doesn't give off his own visible light, but he certainly emits x-rays on his own.

This scales higher:

In this new-but-similar scenario, you're flying over England. You're trying to take a picture of Bob and his lazy ass, but all you can see, no matter how much light you shine down onto the city below, are the lights from the buildings, bridges, and streetlamps. There's just too much noise to find ol' Bob in that galaxy of lumens.

You've got all these lights shining on Bob, but unlike the first scenario, there's /too much/ light to see Bob; all you see are stars, so to speak, drowning out the nearby planets. Well, in x-ray mode, your camera can see that while those stars are emitting x-rays, so is Bob, just like before. You're not seeing a faint image of Bob drowned out by the only light illuminating him, you see Bob's x-ray signature approximately ten feet to the right of that cluster of streetligts.

The universe is a dark place, but sometimes it can be TOO bright! It's a good thing I remembered a towel!

Re:In space no one can see your color?

Resolution. Most space cameras work by detecting light falling on a CCD (Charge-Coupled Device); if the camera was full color, then the resolution would be cut by at least 2/3 because you'd have to devote 1/3 of the CCD to each of the primary colors. (It might be even worse than that if your imaging system wasn't 100% efficient at directing the color components to the proper pels on the CCD). You can obtain the effect of a color camera by using different lens filters and taking multiple pictures and then composing them into a single image - this is what's usually done when a color photograph is desired. By doing that you can produce an image that's exactly what you could obtain with a color camera, but at a higher resolution and without having to use a higher resolution CCD. Also, that way your pictures aren't limited to using a selection of color components that are compatible with those the human eye sees - you can use the filters to "see" parts of the spectrum outside the range that's visible to the human eye.