Ceres, More Fresh Water Than Earth!?, From Space.com Options

[Decepticon]

Fans of Ceres will find this article interesting.

The 200 Plus Images are something I would love to get my hands on. Rotation animation Anyone!?


http://www.space.com/scienceastronomy/0509...res_planet.html

[JRehling]

Fans of Ceres will find this article interesting.

The 200 Plus Images are something I would love to get my hands on. Rotation animation Anyone!?
http://www.space.com/scienceastronomy/0509...res_planet.html

HST raw images tend to eventually end up on the query-able release site... it depends on what is proprietary and for how long... I made a color composite from HST Ceres images as far back as '97.

[Decepticon]

Have you posted those yet? I would love to add that to my Ceres archive.

[David]

Interesting images. I've been comparing them with earlier telescopic images. The bright spot is definitely something new. It seems to me that Ceres is divided into lighter and darker colored halves, though the boundary is more irregular than the one on Iapetus (and the albedo differences are not so great). "Piazzi", presumed to be a crater, is a dark circular or oval formation somewhat more than half surrounded by lighter "arms" or lobes. I believe this formation is observable in the new pictures as well (though possibly it is simply a similar formation located on the opposite side of Ceres from the older images). In any case, the very bright spot is located approximately in the center of the light hemisphere and is definitely not seen on the older images. Possibly the region in which it occurs was not previously imaged, but I do not think so. I am wondering whether Ceres may, through some strange mechanism, be active. Enceladus is smaller, and yet turns out to be far more interesting than expected. Might not Ceres be more than an inert lump of ice and rock? Even if it turns out that Ceres is inactive, the composition of the bright spot should be very interesting.

[edstrick]

Ceres has long been suspected to be more than a totally undifferentiated ball of hydrated silicates. It's further out in the belt where things with water of hydration in minerals start to show up and S-types are declining or low in abundance, I can't recall if it has some in the infrared spectrum... stuff like Serpentine type minerals (hydrated olivine/pyroxene)

It continues to be astonishing how un-battered it looks. Pretty smooth circular limb and no obvious gouges and big-mother craters as it rotates. A planetino indeed!

We've been all hot about Vesta for years, with it's basaltic spectrum and probable pieces in meteorite collections, but what about the other "Big 2".. Juno and Pallas. One or both has very non-usual specta, not all that similar to other asteroids, though nothign really spectacularly unusual like Vesta. Juno, I think is in a very high inclination orbit.

[SigurRosFan]

Hubble Press Release Images: Largest Asteroid May Be 'Mini Planet' with Water Ice

http://hubblesite.org/newscenter/newsdesk/.../2005/27/image/

[Decepticon]

Looky Looky a great animation of Ceres rotation!

http://hubblesite.org/newscenter/newsdesk/...2005/27/video/a


I wonder how image stacking would help bring out more detail on Ceres.


EDIT: Opps! SigurRosFan Beat me to it.

[Jyril]

It continues to be astonishing how un-battered it looks.  Pretty smooth circular limb and no obvious gouges and big-mother craters as it rotates.  A planetino indeed!

Well, a body of its size is easily spherical, and with Hubble's resolution not much is visible anyway. It could be saturated with smaller craters.

Juno, I think is in a very high inclination orbit.

No, it's Pallas which has very inclined orbit. Juno is by far the smallest and the most irregular of the first four asteroids.

[tfisher]

http://hubblesite.org/newscenter/newsdesk/...2005/27/video/a
I wonder how image stacking would help bring out more detail on Ceres.

Unfortunately, I'm pretty sure this animation is *not* a series of Hubble images, but rather a simulation based on a surface map based on Hubble images. So its of no use. You need to get the original images to work with.

[dvandorn]

So, it's relatively obvious that the largest of the main-belt asteroids (Ceres, Vesta, Pallas) are differentiated objects. My curiosity is whether or not these objects must have differentiated "in place," in other words, only in the context of their current mass, size and position.

Could they have once been part of a larger differentiated body that was destroyed by a massive impact? I guess we need a lot more data about the large asteroids, but I'm wondering how small a body can be and still undergo differentiation. When you consider that the Moon apparently is still predominantly made up of undifferentiated chondritic material, sandwiched between a once-molten core and a differentiated mantle and crust, we know that a Moon-sized body does not completely differentiate... and we also suspect that the Moon was formed by a giant impact which completely destroyed a Mars-sized body (which would have to have contained a lot of chondritic material for the Moon to contain a lot of it), so 1) the Mars-sized impactor must not have completely differentiated, and 2) lunar differentiation may not fit into a model of differentiation for primarily-accreted bodies.

Ceres lander/orbiter mission, anyone?

-the other Doug

[MizarKey]

Ceres lander/orbiter mission, anyone?

-the other Doug

Indeed -> DAWN mission to Ceres/Vista

Eric P / MizarKey

[SigurRosFan]

Basic data of the Dawn mission:

Launch - June 17, 2006

Vesta arrival - October 2011

Ceres arrival - August 2015

[gpurcell]

Killing the magentometer seems like a particularly bad idea right now....

[David]

Could they have once been part of a larger differentiated body that was destroyed by a massive impact?

That's the Good Old Theory, isn't it? I seem to recall that the "original fifth planet" played a role in some of the rollicking old space operas of the '40s and '50s. Then it was decided that any possible planet, even with the mass of the whole Main Belt, would have been pulled apart by Jupiter before it could ever form.
I'm not sure how reliable my logic on this is, but it seems to me that if Ceres is still spherical, it would have had to have formed in situ rather than as a result of a collision -- I don't think it's so big that, if it originated as an irregular fragment of a larger body, it would necessarily pull itself back into a sphere; compare the much larger Iapetus, which was evidently badly knocked about earlier in its history, and still shows the evident signs. Still, I suppose DAWN will tell us a lot more about Ceres' history; unfortunately we'll have to wait a long time for DAWN to get there!
Perhaps MER and Cassini will keep going long enough to keep me from getting bored. Ideally I'd like these missions to overlap enough that there will always be images coming back from some corner of the Solar System!

[ljk4-1]

I recall an illustrated story from a late 1970s graphic SF magazine about two astronauts who come upon a large smooth black sphere in the Planetoid Belt.

They can't figure out what it is and toss around all kinds of theories, until one of them thinks it may be the core of what was left of a gas giant planet that was somehow destroyed ages ago. They come to this conclusion just as the laser drill they placed on the black ball's surface starts cutting through....