
Ceres Spots Continue to Mystify in Latest Dawn Images - magicmu
http://www.nasa.gov/jpl/dawn/ceres-spots-continue-to-mystify-in-latest-dawn-images
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beaner
Does anyone know what kind of processing these images go through? Does Ceres
receive enough light for the satellite to see it plain, or is this the result
of X-ray vision or something similar? And the bright spots - I can understand
those being the result of ice reflection, but they seem to absolutely glow in
these images. I imagine that's the result of some filter or processing making
them pop. Is that accurate?

~~~
Mithaldu
Damn good question. Short answer: The images are brightened visible light.

The wikipedia article has more information:

[https://en.wikipedia.org/wiki/Bright_spots_on_Ceres](https://en.wikipedia.org/wiki/Bright_spots_on_Ceres)

Notable points:

In infrared the spots are darker or equal than surroundings, thus cooler or
equal.

In lower resolution pictures the bright spots are _considerably_ larger than
their now apparent size, thus they're throwing out massive amounts of light,
likely reflection of sunlight.

They seem to reflect equally well from _any_ given viewing angle, thus
whatever their material is seems to exhibit some kind of cat's eye effect. (
[https://en.wikipedia.org/wiki/Cat's_eye_(road)](https://en.wikipedia.org/wiki/Cat's_eye_\(road\))
)

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oofabz
The cat's eye effect only works when the light source and the viewer are in
roughly the same place. In a car, light from the headlights is reflected back
at the driver. It wouldn't work for the Dawn probe because there is no light
source on the spacecraft.

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Pfhreak
Couldn't the probe be between the sun and Ceres, causing a similar effect?

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personjerry
Maybe I've been reading too much science fiction, but imagine how cool it
would be if it were some constructed light source.

And just like that, humanity was thrown into the midst of all the other
interstellar species.

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IndianAstronaut
It somewhat reminds me of the book 'Eon' by Greg Bear, where a mysterious rock
shows up in earth's orbit.

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ChuckMcM
Very cool, they have outlasted my projections of how long they would be
mysterious :-) As I've said before my bet is on water ice but the 5,000 meter
"ant hill" is pretty impressive too. I suppose that Ceres is an ice ball with
a dusty covering you might be able to generate a water volcano with the right
conditions, still that is a lot of material to move around.

On commentator suggested that it could also be crystalline diamond, although
how a crystal would cool slowly enough to grow large enough to be visible at
this distance beggars the imagination. I consider that a long shot of the
longest kind.

But people who object to the ice theory accurately point out that water ice
would generally sublimate when exposed to vacuum in the presence of nearly any
energy at all. Much like it does on Mars as shown in Opportunity's tire
tracks.

Crystallized ice in hard vacuum exposed to sunlight seems an improbable thing.
A shiny chunk of Nickel though ...

~~~
tgflynn
What about large quantities of quartz crystals ? That would seem much more
probable than diamond and wouldn't have the sublimation problem of water ice
in a vacuum.

~~~
ChuckMcM
Certainly possible, except that quartz crystals grow in hot watery solutions,
and those are equally hard to come by in space.

It would be interesting to stack up the set of conditions that would need to
be true for them to form, perhaps a watery core undergoing tidal heating while
silica dust is deposited on the surface and transported by meteor impact into
the internals of the asteroid. A lot of steps though.

For what its worth its also why the metals idea are statistically unlikely, as
the distillation out of various metals would be hard to explain.

That also makes the puzzle exciting though, the harder it is to guess what it
is, the more interesting the answer in my experience.

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IvyMike
I understand we're going to get photos from a lot closer, but does anyone know
what the best resolution will be? (I guess, how much improvement can we
expect?)

Because if we can't resolve the mystery from photos, I'm all for sending a
lander. I can't stand not knowing.

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jccooper
Low altitude mapping orbit, Dawn's final destination (at around December),
will be 230 miles (375 km) up, and will have a resolution of 120 ft (35 m) per
pixel. Currently it's about 410m per pixel. So it's going to get a lot better.

[http://www.jpl.nasa.gov/blog/2015/3/let-the-discoveries-
begi...](http://www.jpl.nasa.gov/blog/2015/3/let-the-discoveries-begin-a-
guide-to-dawns-exploration-of-dwarf-planet-ceres/)

Will that be enough? Probably.

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suprgeek
<Please><Please> Abandoned alien city.

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Frostywombats
It'd be fascinating if it was primitive life - some form that doesn't require
water to sustain. Would definitely throw some perspective into the very earth-
centric idea of life

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Symmetry
If I had to guess I'd say that the mounds are related to the water volcanoes
we saw earlier.

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Mithaldu
A site that not only breaks completely, but has literally no content without
JS?

Et tu, NASA?

~~~
magicmu
Hah I didn't even notice that, you're right! It looks like it uses Drupal too,
so they must have a... limited dev budget for their web presence

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brock_r
Maybe it's about to turn into a star?

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Zelphyr
No. Only if we identified a massive number of black monoliths converging on it
would that be a likely outcome.

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egfx
How about that pyramid?

