Dawn at Ceres Thread

[vger]

Here's a recent update on the situation: http://www.space.com/29043-dawn-spacecraft-one-month-ceres.html

Is all of this conjecture based on when they last saw it before it reached the 'dark side?' Are they still getting a signal? I was under the impression that we had to wait until it emerges again, to know if everything is still running smoothly.

[-ctn-]

Is all of this conjecture based on when they last saw it before it reached the 'dark side?' Are they still getting a signal? I was under the impression that we had to wait until it emerges again, to know if everything is still running smoothly.

Being on the dark side doesn't exactly mean blocked by the dark side of the planet.

Just means that any photos we get are going to be mostly, if not all, black because there's no sunlight reaching the side we would see.

I was hoping any OpNav photos would show a crescent, as the resolution would be greater than before.

http://dawnblog.jpl.nasa.gov/wp-content/uploads/2015/02/Full-approach.jpg

[Kryten]

It's not over the 'dark side', it's over the actual dark side; we aren't receiving images because they aren't being taken. We're in full contact with the spacecraft, we're just not burdening the DSN with data that we know will not include useful or interesting.

[-ctn-]

But doesn't the AutoNav (I'm assuming similar to the DS1 program) use photographs to help orient itself? So aren't the guys at NASA getting photographs anyway for course corrections?

[Kryten]

Dawn OpNavs are quite far apart; the last was on March 1st and, as far as I can tell, they're still working to the schedule here, meaning the next is/was sometime today.

[-ctn-]

http://dawnblog.jpl.nasa.gov/

"...when Dawn spies the thin crescent of Ceres in its next optical navigation session, scheduled for April 10..."

"...on April 14 (and extending into April 15), Dawn will obtain its last navigational fix before it finishes maneuvering..."

EDIT: Sorry, I misunderstood what you were getting at.

I knew that, I was just complaining that they haven't released the OpNav photographs from today yet, as I was anxious to see any pictures of Ceres in higher resolution.

Edited April 11, 2015 by -ctn-

[PB666]

I was starting at a blow up of Nasa psuedocolor Ceres image

http://www.nasa.gov/jpl/pia19063/dawns-first-color-map-of-ceres/

And I see tracks or rifts on the rightish side of the photo.

4 of them seem to coalesce into what appears to be the bright spot (can't say for sure because this is psuedocolored.

Nasa claims the spots are cooler than surrounding terrain, which means these are probably of a reflective nature.

If this was of a techtonic nature one might expect them to be dark, I don't know of any techtonic activity the produces white colored igneous (unless it was gypsum or quartz).

Any thoughts?

[Technical Ben]

Is it true colour or adjusted for contrast?

Is it the colour of the material or scattering due to it's texture?

It's cold. Is it gaseous/liquid and not just rock?

[Frida Space]

A global color map of Ceres! http://t.co/6pZZzq1u2u

[Hcube]

Are those real colors, or are they added to highlight something ?

[lajoswinkler]

Those are not real colors, of course. That's not only extremely saturated, but also includes good part of UV and IR. So it's false color.

[lajoswinkler]

It is false color (VIS broadened by UV and IR) and extremely saturated. Your eyes would not see this.

It can not be gaseous or liquid. Ceres doesn't have an atmosphere.

[Darnok]

Anyone else spotted pentagon?

[Nibb31]

What I see is too many compression artifacts to see much detail. Chances are the "tracks or rifts" you are seeing (I'm not seeing anything of the sort) are simply due to the compression algorithm and the poor resolution.

[Nibb31]

Saturated and inverted. The process is explained in the link.

[Technical Ben]

Yeah, sorry. I meant as in frozen gas. As that's a thing we tend not to get here, but can happen in space, and thus be colours we would not see on earth. Rock on earth would then be a different colour at times as it would have no ice content.

[-Velocity-]

It's not over the 'dark side', it's over the actual dark side; we aren't receiving images because they aren't being taken. We're in full contact with the spacecraft, we're just not burdening the DSN with data that we know will not include useful or interesting.

We don't really know for sure what will be useful and interesting, it's a new world. For all we know, if we take an image of Ceres' night side at the right time, there will be a back-lit plume of dusty water vapor or something, kinda like we see on Enceladus when Cassini takes back-lit images of it from a distance. One of the leading candidates for the bright spots is, after all, a water vapor plume. Honestly, wouldn't it be smart to try taking an image of Ceres from its night side when the bright spot is on the limb, just to see if it rises from the surface into space some?

[Vanamonde]

Threads merged. Let's keep the discussion of Ceres imagery all in one tidy place, please.

[Frida Space]

Ceres is out of the dark, as seen by Dawn! Taken on April 10th from 21k miles (33k km). The center of the image is roughly Ceres' north pole.

[Frida Space]

Here we go again:

This time from 22k km.

[LordFerret]

Looks to me like the bright spots, as seen in the second image posted above, will turn out to be nothing more than very shiny reflective surfaces ... like ice, or glass-like.

[Frida Space]

Looks to me like the bright spots, as seen in the second image posted above, will turn out to be nothing more than very shiny reflective surfaces ... like ice, or glass-like.

That's what I always thought. But could it explain why they are visible for a brief time even after local sunset?

[Brotoro]

The ice (or whatever) patches would just need to be at high elevations to bee seen as the surrounding landscape fell into darkness.

[Streetwind]

Dawn arrived at the science orbit on Thursday (April 23), spiraling down to an altitude of 8,400 miles (13,500 kilometers) above Ceres, NASA officials said. The probe achieved this milestone on schedule, but not without a bit of drama.

Let the science begin!

[lajoswinkler]

Take out your red-cyan glasses.