Cassini Shows Close Up of Iapetus

dazza101 writes "The Cassini spacecraft passed within 72,000 kms of the Saturn moon Iapetus yesterday, taking a series of spectacular images of this intriguing moons rugged surface. An excellent prelude to what promises to be one of the major stories of the new year, the plunge of the Huygens probe into Titan's atmosphere on January 24."

If that's no space station, what is it?

[IO ERROR]

Iapetus doesn't concern me. What concerns me is Mimas [nasa.gov], which has a clearly visible crater with a mountain inside it [nasa.gov].

I have a hard time believing that's a natural formation. And I'm concerned that whatever did it might still be bouncing around the universe somewhere.

Anyone have any idea what could have caused a formation like that?

Re:If that's no space station, what is it?

[Scoria]

I have a hard time believing that's a natural formation. And I'm concerned that whatever did it might still be bouncing around the universe somewhere.

We should only be concerned about Europa.

Re:If that's no space station, what is it?

[IO ERROR]

We should only be concerned about Europa.

Europa? But I'm an American!

Re:If that's no space station, what is it?

[kubrick]

"All these worlds are yours, except Europa. Attempt no landings there."

Re:If that's no space station, what is it?

[Anonymous Coward]

Yep, that's a moon alright.

Re:If that's no space station, what is it?

[Pinkfud]

That's a "rebound effect". Whatever caused that crater was so big and hit so hard that it penetrated the moon's crust. The more plastic inner material was violently compressed, then shot out through the center of the crater forming the "mountain". It's a rare phenomenon, but I don't have any trouble believing it's natural.

Re:If that's no space station, what is it?

[Turing Machine]

You can see a similar phenomenon in these high speed photos of water droplets [rit.edu].

Re:If that's no space station, what is it?

[adeydas]

And a similar phenomenon is happening here on Earth too. The Himalayas were formed due to the impact of peninsular India when the continents were formed. Well as a 'repulse' to the imapct, peninsular India is now slowly shifting away from the Himalayas. Can this be called a product of Newton's third law on a much greater scale?

Re:If that's no space station, what is it?

[pyr0]

You need to take a basic geology course (as well as whoever modded you informative). Not only is the Indian/Australian plate still colliding with with Asian plate, but the process of forming a high point at the center of a meteor impact is nothing like the slow collision of two tectonic plates.

Re:If that's no space station, what is it?

[dn15]

And I'm concerned that whatever did it might still be bouncing around the universe somewhere.

Even if it is, does it matter? I don't see how this would be any greater cause for concern than the objects that made other huge craters on other planets/moons/etc. I mean, respectfully, it's not news that there are big things floating out in space, or that some of them have collided with other objects. And if it does head our way, I have faith in Bruce Willis.

Re:If that's no space station, what is it?

[Anonymous Coward]

Large impact craters are characterized by central peaks. This type of crater ("complex impact crater") is common on the Moon, Mars, Earth, and all other bodies with impact craters. The peak forms by rebound of the crust. This page has some details: http://www.solarviews.com/eng/tercrate.htm

Re:If that's no space station, what is it?

[Forbman]

Just watch early slow-motion films of water drops landing on water. With the rebound peak on the moon/planet/whatnot, it seems that it cooled fast enough during the rise to not fall completely back in on the way down, relative to the macro-level viscosity of the material in the disturbance.

Re:If that's no space station, what is it?

[rockwood]

That picture lacks the true depth of the crater. Check out THIS PHOTO [earthlink.net] for a much more accurate detail

Re:If that's no space station, what is it?

[pediddle]

If by "more accurate detail" you read exaggerated artificial relief done with Photoshop, then by all means, check out the photo.

I'm more worried about Mars.

[Anonymous Coward]

Or, more precisely, the geometric object that crated on mars:

The mars golf ball [usgs.gov].

At a guess, it's a glob of molten rock that condensed into a sphere in orbit before hitting the surface again. But that still doesn't make me want to see more detailed photographs and information about it so very, very badly. It would probably be one of the most impressive sights on the Martian surface.

Re:I'm more worried about Mars.

[mpthompson]

Just a guess on my part, but the object in the crater looks more like dunes of sand blown into and protected by the crater than an intact blob of something that fell from orbit. Regardless, it would be interesting to see a higher resolution picture.

Re:I'm more worried about Mars.

[Nerull]

You also have to remember that shadows can play tricks with your eyes in pictures like this. Craters can look like buldges, etc.

Re:If that's no space station, what is it?

[Squid]

Here's [space.com] a crater on the Moon with such a peak. I guess it really gets around.

They're called rebound peaks and they are a common feature of impact craters, and perfectly natural.

Re:If that's no space station, what is it?

[The Journalist]

Cheney should be very worried now. NASA's found his prototype Death Star.

Re:If that's no space station, what is it?

[Spunk]

Are you sure that's not Senator Lieberman's [geocities.com] Death Star? :)

Re:If that's no space station, what is it?

[Arngautr]

Anyone have any idea what could have caused a formation like that?

A meteorite.

Re:If that's no space station, what is it?

[IllForgetMyNickSoonA]

Asteroid, actually. Meteorite is an asteroid burning in the atmosphere (aka "shooting star"). As far as I can remember, Iapetus does not have any atmosphere worth mentioning. Check this [aerospaceguide.net] for details.

Re:If that's no space station, what is it?

[Arngautr]

A meteor is one that burns up (any body's atmosphere), a meteorite is one that hits, an astroid is one out in space. Your link even says this!?!

Re:If that's no space station, what is it?

[IllForgetMyNickSoonA]

Uhh... embarrasing. :-) I read "meteorite" and parsed that as "meteor" (for which reason whatsoever). Please receive my appologies - you were right, I was wrong.

Re:If that's no space station, what is it?

[Angry Toad]

Another feature I'm quite curious about is this globe-spanning ridge [nasa.gov]. I haven't seen any mention of it anywhere yet.

It seems (though I may be wrong) to sit dead-center on the darkened portion of the moon and span much of the length of the dark part as well. Is there a connection perhaps? I'd be interested in the opinions of any planetary astronomers.

Re:If that's no space station, what is it?

[k4_pacific]

The moon is hollow to save material. That is the seam where the two halves were welded together.

Re:If that's no space station, what is it?

[Lispy]

Hey, darn. That's my hidden citadel. Now I gotta move my lair to another moon. Muahaha...

Re:If that's no space station, what is it?

[dukerobinson]

that is clearly the moon's "primary weapon" obviously this station has gone long unused as it is covered in "space dust"

Re:If that's no space station, what is it?

[Winkhorst]

The crater in question resulted from a very rare toroidal meteor. Because of its shape the meteor rotates and is often mistaken for an alien space ship. Because these meteors are metallic, they generate an electromagnetic field that distorts brainwaves in such a manner that observers think they are seeing aliens.

This public service announcement was brought to you by the Martian Defense Force, who, we repeat, is not interested in invading your wonderful little planet...

Cassini Hyugens

[metlin]

Cassini Hyugens sounds like the name of a Scandinavian supermodel or something.

And here I was hoping for some spectacular pictures :-(

What do I see? Big round thing with holes. Different, but not the way I imagined :-/

Re:Cassini Hyugens

[pv2b]

Big round thing with holes? Astronomy-related story?

Hmm.

Could this be the perfect time for...? Yes it could.

This remind you of somebody you know? [nasa.gov]

Re:Cassini Hyugens

[metlin]

Well, talk of heavenly bodies of the wrong kind :-(

Re:Cassini Hyugens

[LS]

I don't know about you, but that big honkin' crater that is a quarter the size of the moon is kinda cool to me. The crater CONTAINS craters...

Hyugens

[dj245]

Cassini Hyugens sounds like the name of a Scandinavian supermodel or something.

10 Geek points for sucessfully pronouncing "Hyugens"! Bonus if you can also pronounce "Reuters" sucessfully.

Re:Hyugens

[johannesg]

I can do both, but I'm Dutch so that helps ;-)

In fact my last name, happily obscured in this forum, also has the same "uy" and the hard "g" sounds, and I know from experience that there is absolutely no way for english speakers to pronounce it correctly. Usually I let people stumble a few times and then tell them to call me by my first name.

I cannot begin to spell "Huijgens" phonetically, but I can tell you this: the common english pronunciation, "Joogens", is wrong. The "H" is the same sound as in the

Re:Hyugens

[StarfishOne]

The phonetic spelling can be found on Dictioary.com [reference.com] .

Luckily, also being Dutch myself, I have no trouble at all pronouncing this word.. but I do like that supermodel thought! ;)

Re:Hyugens

[snake_dad]

And 10 slashdot-editor points for getting the name Huygens wrong! *slap*

Iapetus

[HuckleCom]

Iapetus: Greek Mythology. A Titan who was the father of Prometheus and Atlas and an ancestor of the human race. Why do we name everything using greek mythology? I mean, sure it sounds cool... but so does foshizzle.

Re:Iapetus

[Guppy06]

"Why do we name everything using greek mythology?"

Because Galileo got frist p0st.

Re:Iapetus

[Mr2cents]

Because christian mythology sucks?

There are....

[deglr6328]

....also many more images if you go straight to the raw feed [nasa.gov].

Re:the other server

[deglr6328]

on second thought, try this [nasa.gov] server instead. Seems to be moving rather faster than the now /.ed "saturn.jpl.nasa" one.

Re:There are....

[Protocron]

I don't think so. Looking at the photo in different GIMP layers, I think it probably is a comet. It might be that one, Comet Machholz [slashdot.org]. Who knows. I'm certainly not going to look for it. The reason is because from right to left it seems to get lighter, much like a comet. I'm not saying that it completely is that, but if you magnify it a few times you see that. Than again who knows? Comet, UFO, killer tomatoes.

Re:There are....

[deglr6328]

I think you were replying to the AC next to me but I'll reply anyway! :o) It's not a UFO and it's not a star and it's not a comet or planet. Its a proton, or perhaps, an electron. Accelerated to relativistic velocities by the soalr wind or saturn's magnetosphere (or both) it struck the cameras CCD at an angle and as it traveleld through, excited some electrons in the valence band of the semiconducting image detection layer to the conduction band, just like a photon of visible light would if it hit the detector and produced a streak in the image. It's called a "cosmic ray hit" and there is software to remove them from the images.

Nice rock but...

[appleLaserWriter]

How does this promise to be one of the biggest stories of the new year? There are tons of rocks out there. What is so special about this one that will make it a huge news story in '05?

Re:Nice rock but...

[brittm]

Perhaps what will make this a big story is simply the fact that we're out there, and we're looking at it.

A baby's first steps aren't very interesting in and of themselves, but they're exciting none the less because they're the tell-tale beginnings of greater things to come.

Re:Nice rock but...

[dazza101]

The first look at a moon with its own atmosphere that may resemble the atmosphere of the early Earth?

Re:Nice rock but...

[Carthag]

The "biggest story of the new year" refers to Titan, not Iapetus.

Does anyone else notice...

[s7726]

Did anyone else notice the fact that the main picture looks like any other picture of the earth's moon?

Not fair, not square.

[Pig Hogger]

Something's missing, like big, square, black thin block.

(No, you won't get it if you didn't read the book).

Re:Not fair, not square.

[MatB]

And after months of lurking, the inspiration to create an account comes from... Have they resolved/explained the weird brightness differential between the orbits? The only reason I clicked on this story was the link to the book, no one else has mentioned it yet...

Re:Not fair, not square.

[el-spectre]

Years ago I read (sorry, can't remember the source) that while Clarke invented the 'black dot' in 1968, humans (actually Voyager 1 or 2) didn't discover it for a few more years.

Nifty, no?

Wow!!

[boomgopher]

Yikes, everyone take a look at this one:
Amazing detail photo [nasa.gov]

Can't wait for others of this caliber!!`~ Made me weep!!



(it's a joke son)

Re:Wow!!

[eam77]

Perhaps they should send that photo to CSI, they have amazing digital photography enhancement capabilities.

Re:Wow!!

[NanoGator]

"Can't wait for others of this caliber!!`~ Made me weep!!"

Wow. Never would expect that Nasa's using a Game Boy Camera...

Titan is a hippie!

[soimless]

http://saturn1.jpl.nasa.gov/multimedia/images/raw/ casJPGFullS06/W00003604.jpg look it made Cassini take LSD!!!

Re:Titan is a hippie!

[Snipes420]

nice, my new desktop wallpaper

Bah...

[el-spectre]

Call me when they find a monolith...

NASA/ESA/ASI

[Anonymous Coward]

The Cassini-Huygens mission is a cooperation between NASA, the European Space Agency and ASI, the Italian space agency. [esa.int]

Wrong date.

[daquake]

The Huygens plunge is January 14'th, not the 24'th :) 2 Weeks is hard enough to wait for! :)

Re:Wrong date.

[dazza101]

You are right! Doh!!!!

What Caused the Ridge?

[Al Mutasim]

Interesting image. The craters look pretty commonplace--but what caused the ridge? It appears to enclose a low-lying area. The border seems too jagged to be a large crater.

Arthur C. Clarke and Iapetus.

[NarrMaster]

In 2001: A Space Odyssey, Clarke described Iapetus as having a black circle painted on it, with a white circle within.

When one of the Voyager probes photographed Iapetus, a "circular" black area was found with a smaller white area within.

Why is this interesting? 2001 was published in 1968. The Voyager probes didn't visit Jupiter until 1980 (V1) and 1981 (V2).

Re:Arthur C. Clarke and Iapetus.

[deglr6328]

Carl Sagan, who was on the Voyager imaging
team, sent him a JPL photo (he was a member on the voyager team) with a note scribbled on the back. it said: "Thinking of you"....

Re:Arthur C. Clarke and Iapetus.

[snake_dad]

And you think Clark thought of it first?

SpaceFlight Now [spaceflightnow.com]:

With a diameter of about 1,400 kilometers (890 miles), Iapetus is Saturn's third largest moon. It was discovered by Jean-Dominique Cassini in 1672. It was Cassini, for whom the Cassini-Huygens mission is named, who correctly deduced that one side of Iapetus was dark, while the other was white.

Not sure how much that vision of the moon has improved since, but going from that to the idea that maybe something went <SPLAT!> on the moon leaving

Re:Arthur C. Clarke and Iapetus.

[NarrMaster]

Its not that one side was white and the other black, its that one side was black with a small white circlish are in the middle. I'm not just going on speculation. I am going on quotes from various people, including Clarke himself and some folks who worked at JPL. They all agreeded it was a coincidence.

Re:Arthur C. Clarke and Iapetus.

[snake_dad]

Alright, I ignored the white inner circle part.

Re:Arthur C. Clarke and Iapetus.

[mikewhittaker]

Given that comets are currently thought of as having a coating of dark carboniferous goo IIRC, it doesn't seem too unlikely that if one hit a small moon, it could leave a black residue, if the impact wasn't sufficient to vaporise and degrade whatever the goo is.

Re:Arthur C. Clarke and Iapetus.

[NarrMaster]

No, it is just a really cool coincidence.

Re:Arthur C. Clarke and Iapetus.

[NarrMaster]

Yes, but most of Iapetus's features were not known until the Voyager fly-bys. These include the white patch within the dark circle.

Isn't it Jan 14th?

[Anonymous Coward]

Isn't Huygens plunging into Titan on Jan 14th??

Re:Isn't it Jan 14th?

[daquake]

Yeah, posted it a bit higher on the page. Is there a place to submit corrections for te actual headline story text?

Re:Isn't it Jan 14th?

[ArbitraryConstant]

The editors generally pick it up.

Or rather, they might pick it up but there's nothing anyone else can do about it but whine. :)

It is

[Konster]

It is clear to me that Mimas is actually the Death Star. I wonder if it fully operational?

Re:It is

[helioquake]

Yes it is. Makes you feel better?

Date in article wrong.

[MythMoth]

It plunges on January 14th, not 24th.

Press Release [nasa.gov]

Obvious..

[Renraku]

That's no moon..

Iapetus Ring

[FrostedWheat]

I've noticed in a lot of the images, there appears to be a ring of mountains around most of Iapetus's equator: Here [nasa.gov], here [nasa.gov] and here [nasa.gov].


I'm no scientest, but is it possible that this moon once had a ring system like Saturn itself? Over time the ring particles fell out of orbit and formed the mountains along the equator.

Re:Iapetus Ring

[odyrithm]

Slartibartfast forgot to remove the mold lines the silly old fart! don't worry I'll get straight on the blower!

Re:Iapetus Ring

[Angry Toad]

My previous post on this topic may be lost in the noise above.

It isn't clear to me that this mountain range extends beyond the "dark zone" - but it does seem to sit squarely in the middle of the dark zone itself. I'm quite curious about NASA's thinking on this ridge, and whether it has some relationship to the dark material.

Re:Iapetus Ring

[Feztaa]

Duh, it's the seam where they cut the planet open to insert the cream filling. All planets have those.

Re:Iapetus Ring

[FrostedWheat]

There is an interesting image of this mountain range here [nasa.gov]. It seems to suggest that the range extends beyond the dark material, tho that area is hidden in shadow. What's interesting here is that the peeks remain clean well into the 'dark zone'. So possibly whatever formed the mountain range happened before the dark material was deposited.

I'm glad someone else noticed this!

Re:Iapetus Ring

[Angry Toad]

If the white mountain line is contiguous with the rest of the "ring" feature then the whole mess is virtually dead-on the equator. Very wierd.

Re:Iapetus Ring

[Tablizer]

I've noticed in a lot of the images, there appears to be a ring of mountains around most of Iapetus's equator: Here, here and here....I'm no scientest, but is it possible that this moon once had a ring system like Saturn itself? Over time the ring particles fell out of orbit and formed the mountains along the equator.

The "ring of mountains" is indeed pretty darn odd. Never seen it on any other moon that I know of, at least not one that extends that far around.

But, I doubt falling ring debri would cause

All these missions seem to end...

[michaeldot]

...with the probes being crashed into things.

Whatever happened to sending them on their way out the solar system with gold discs in them containing the sounds of Earth and diagrams to show the little green men where to find us?

Oh well, maybe it's just yet another thing George Lucas has to answer for.

Re:All these missions seem to end...

[snake_dad]

At the risk of trollbating... Missions like Pioneer 10/11 and Voyager 1/2 were fly-by missions. They were accelerated to tremendous speeds by one or several gravity assists, and thus merrily went their way out of the solar system. More recent missions are designed to enter orbit around the targeted planet, and to achieve orbit they have to slow down a lot. It would cost a huge amount of fuel to get them going again fast enough to exit the solar system, and all that fuel would have a big impact on how much instruments could be carried along.

Some missions (like Galileo) were indeed crashed onto the target planet to prevent them becoming a problem later, or to use the impact as a science data point. Other missions were crashed quite unintentionally.

Re:All these missions seem to end...

[lime1304]

A "problem" meaning Cassini could bring microbes from Earth and contaminate another world. The purpose of crashing Galileo into Jupiter was to prevent a possible crash into Europa. Since Europa may have a warm water ocean below its icy crust, it has the possibility of harboring life. It is possible that there is now life on Mars, because it was brought there with the Mars rovers.

Re:All these missions seem to end...

[snake_dad]

Exactly. I seem to remember that Galileo did not go through the very intensive sterilization process that the rovers went through. But there's always a chance of course...

Re:All these missions seem to end...

[earthforce_1]

The two voyager missions took advantage of a rather unique alignment of the outer plants, that allowed for a grand tour. They also did a lot of the ground work in finding targets for future study with the subsequent Gallileo and Cassini missions.

14th not the 24th

[PingXao]

The Huygens probe will enter Titan's atmo on 14 January, NOT the 24th. Is it so much to ask that the dates you report are accurate?

Handy we have an atmosphere

[kurt555gs]

Looking at this moon I am really thankfull the earth has an atmosphere, or we would be as poc marked as this moon is.

Re:Handy we have an atmosphere

[jfengel]

Not to mention the whole breathing thing.

Re:Handy we have an atmosphere

[MonkeyCookie]

The atmosphere does provide some protection, but many meteors still hit Earth anyways. We just don't see as much pockmarking, because the Earth's surface has lots of water (75% of the surface) and the ground is not just hard rock. Not only that, but meteor craters don't last as long because weathering, erosion, and plate tectonics.

It could have taken billions of years for that moon to accumulate all the pockmarking. Such craters on Earth generally disappear without a trace in less than a million years.

Re:Nasa needs better cameras.

[daquake]

Heh, if you have a webcam that can withstand solar radiation, temperature extremes, and run for 7 years with no problems, I'd ebay it :P

Re:Nasa needs better cameras.

[sacredchao]

Also, resolution ain't everything. You can bet that this camera, like the mars landers and unlike your generic handheld digi-camera has a CCD an inch or two wide rather than a few millimetres. Good light sensitivity makes up for a lot. Big chunky pixels in the CCD mean fewer dead black spots from radiation and suchlike as well.

Re:WRONG DATE !!! Huygens descends on the 14th.

[eclectro]

Actually submitter is right.

The probe does descend into the atmosphere on Jan 14th, but it takes an additional 10 days to photoshop the results.

Re:again the /. "editors" screw up

[dazza101]

Not now :-)

Re:again the /. "editors" screw up

[daquake]

Oi... if only mod points were as proliferate as the morons in my daily life (LA Drivers) ;).

Obviously this wasn't a failure to check the article (random guesswork) - though it could have been, but rather a simple typo. Not even the machines that run the Slashdot editors are perfect :P

Re: Iapetus picture

[some guy I know]

http://saturn1.jpl.nasa.gov/multimedia/images/raw/ casJPGFullS07/N00026377.jpg [nasa.gov]

What I thought was more interesting about that picture was the streaks (mid-lower right and top middle).
Are they particles that are part of Saturn's rings?
(There are also several white dots and a white streak in front of Iapetus, but I assume that they are caused by artifacts, cosmic rays, or transmission problems.)

Re: Iapetus picture

[darenw]

Those streaks are stars, making trails as Cassini moves during the long exposure of 82 seconds.