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Comment by keyle | Hacker News Reader

I'd love the crazy theories to come out about those white spots. Anyone?

At first glance, it looks linked to the center of that massive crater. Could it be an active volcano of sorts?

So a 'complex crater' involves a certain degree of subsidence of the uplifted outer rim, and the forces involved in this subsidence, spreading the underlying rock, combine at the center to push material upwards into a small solitary peak. I always assumed this happened due to a continuous pressure of magma or something in volcanoes, but it turns out the effect happens regardless of and in addition to any underlying geothermal activity: it's a feature of gravity and long-term settling of annular structures.

http://en.wikipedia.org/wiki/Complex_crater#mediaviewer/File...

It looks like this is a crater which has ice(water ice? CO2 ice?) underlying a thick, mobile dust layer. When Ceres suffered an impact at some point in the past, it excavated a crater in the ice and dust, then the dust settled back down, covering everything. Over the following millennia / eons, the crater rim subsided and the center entered a long period of slow uplift, pushing through the dust layer and exposing the ice.

It's possible something more novel could be at work here involving phase changes and maybe cyclical patterns; Unpredicted seasonal geysers have been observed on Mars, as an example. A complex crater filled with dust over underlying ice, though, is probably the default assumption.

Abandoned, but fully operational, alien base. We send humans there, land successfully, discover we are not alone in the Universe, and Humanity is united behind the effort to gain deeper understanding of ourselves. Also, there's a hidden door somewhere in the base that leads deeper into the interior of Ceres, where we discover .. the whole thing was a station.

A man can dream.

It's a massive radio telescope reflecting the sun.

See how the Effelsberg 100m RT looks from a satellite:

https://www.google.com/maps/place/50%C2%B031'29.0%22N+6%C2%B...

In Alastair Reynold's scifi novel Pushing Ice, it wasn't Ceres, but another body in our solar system that with an apparent origin similar to what you've imagined...and behavior just too interesting for the curious primates to ignore...

Eon was another good book which investigated this possibility of an alien rock orbiting earth.

And then we discover that Charon is in fact a mass relay...

Yes, I have such dreams too, sometimes.

"Assuming direct control."

Link it with the recent mysterious high altitude dust clouds on Mars and it could be the prelude to something exciting or downright nasty, if you read as much science fiction as I do.

http://blogs.discovermagazine.com/d-brief/2015/02/17/mysteri...

That would be amazing. It would be so exciting to live through that.

Why does that description sound like the beginning seasons of lost?

The not-crazy theory is that this is a chunk of ice uncovered by the impact that created the crater they are in and that they reflect the sun.

If so it would be some sort of ice volcano. I didn't find where it said what the spectrum was for the camera, infra-red? visible? something else? One theory for it is that it is a dust covered ice ball, a large enough impact could uncover the ice (although I would expect there to me a sublimation cloud at that point.)

If the core is nickle iron it could be a chunk that melted and reformed after impact.

Or it could be a bad pixel :-) but that seems unlikely as it moves with Ceres and not with Dawn.

A recursive portal into the far, far distant future; billions of years in fact. Once entered, there would be no way back for physical bodies, however, radio transmissions could find a way.

My crazy theory: naturally formed nuclear reactor.

Not far-fetched at all. There's precedent right here on our home planet:

http://en.wikipedia.org/wiki/Natural_nuclear_fission_reactor

Ceres is as old as Earth, so its Uranium should be as lowly enriched in U-235 as here, which is today too low for natural reactions. Additionally it would be highly unusual for Ceres to have concentrated Uranium ore deposits to a similar degree as Earth, for mineralogical reasons.

You need water for this to work. Is there water on ceres?

Quite possibly: http://www.nbcnews.com/science/space/there-life-ceres-dwarf-...

My crazy theory: you think it was a coincidence that, just as our spacecraft approaches Ceres, a defense satellite in Low Earth orbit 'mysteriously' explodes? Pah! That's just what they want you to think!

Awesome.

I'm curious too, so I was glad to read that the probe will get about 10x closer, and of course being there permanently means there should be some benefit from cumulative observations until such time as the power/equipement runs down.

Edit: it's entertaining to think about what results would create a scramble for a follow-up mission to exploit it.

As mentioned in some of the comments to the posted article, I want to know if getting some spectroscopy on those white spots couldn't be possible. Perhaps summed over a quite long series? (Wouldn't it be a thrill if they were metallic?)

According to the comment by Marc Rayman "We have obtained visible and infrared spectra every time we have acquired images. The results are not ready for release."

I don't think you'd get much from a spectrum. It's all (likely) reflected sunlight. It's not emitting light, so there are no emission lines, and it's not absorbing light, since there's no atmosphere.

The lack of atmosphere actually helps, as the spectroscopy will be more accurate.

I would guess that it's a very reflective crystalline structure. You can see that as the bright structure goes beyond the terminator, it is still visible for a frame, but it completely disappears the frame after. It's hard to say either way though as we don't know the specs of the camera. Lots of materials reflect light differently at wavelengths outside our normal vision.

They concluded some of the mineralogy of the asteroid Vesta using spectroscopy ... http://solarviews.com/eng/vesta.htm

You'd get some from info. Different materials have different reflection curves, especially if they can also image infrared.

Just subtract the known spectrum curve of the sun, and check the difference.

Ceres could be the Death Star. Or the main component of Hactar.

Could they be ice or metallic material?

Everybody would be disappointed if they were not the eyes of an exogorth staring at the probe and waiting for a lunch after so many years.

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