From Twitter:

Vishnu Reddy @moonyguy

We are getting the good stuff from OpNav2 from @NASA_Dawn of #dawn_ceres, first images look very impressive.

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Let's hope we have them at the end of the week!

EDIT - Habukaz beat me to it!

Phil

I was playing around with Celestia this morning and I finally managed to get Dawn to work in that program. So without further ado, here are three animations for the first two opnav observations plus one for the next one which appears to include a satellite search observation...

Opnav1
Opnav2
Opnav3/(+satellite search?)

Now, my big concern now is making sure Ceres is right. I'm not sure I have the rotational model right. Right now it is just using a uniform rotation model. For one thing, the bright spot isn't the right bright spot...

To follow up, here are a new set of videos, which include the three rotational characterization observations (RC). For these videos, the left panel is a simulation of the Framing Camera field of view (give or take a few minutes of arc) while the panel on the right shows orientation of the Dawn spacecraft. Each video covers roughly 25 hours, running at 1000x speed.

OPNAV1 (January 13)
OPNAV2 (January 25)
OPNAV3/Satellite Search (February 4)
RC1 (February 12)
RC2 (February 19)
OPNAV4 (February 25)

EDIT: working on updated versions with Ceres working as it should this time. I'm using Phil's map now with a slight correction in longitudes (I think I shifted things 20 degrees to the right so that it better matches with other published maps). An issue I've run into though is that the Dawn team seems to be once again going there own way when it comes to Ceres longitudes, with the IAU using one prime meridian, and the Dawn team using another. I am going to just use the Dawn team's one, it seems to matches best with published maps.

EDIT2: I've uploaded new versions of these videos, now with the proper rotation model used for Ceres. I'm also using an updated version of Phil's map that now matches up, at least longitudinallly with various published albedo maps (specifically, I used the one posted here, a page about the first opnav image that I haven't seen posted here).

as nice as it is to see a new planet the first time, remember we are still at only ~20 kilometers per pixel. Enough to see markings but interpretations are still going to be 'interesting'.

for fun, here is a tethys image at similar resolution, interpretable because we have the global high res map. the curvilinear markings are Ithaca Chasma and a large relaxed basin (Telamus).

And images like this of Tethys are the exact reason I mentioned Ithaca Chasma in my post above containing the stacked image

I'm finding it remarkably difficult to wait for the higher-res images obtained today - they should be very interesting.

That's for sure. These are the first ones that will propel us from Hubbly guesswork into a completely new era of what we know about Ceres.

It's also the most interesting entirely new object of its size and significance since what...Neptune maybe?

Will the new opnav images be looking at the same hemisphere as the last set? In other words, will we be seeing the white spot at greater resolution, or the other side?

Don't get me wrong, I don't care which side we get to see. I'm happy to see any of Ceres at ever-increasing resolutions. This will help complete my mind's-eye-view of our solar system, and I can hardly wait.

Of course, the remainder of what I need for that wonderful full visualization of our solar system has to wait until July, at the earliest. So, no matter what, there is always more time to wait... but wonders at the end of the rainbow.

-the other Doug

It will be the same side. i think a more complete rotation is the one planned Feb 12 or so. when we should have ~115 pixels on the disk. can't wait . . . by then the new leaves will start here in houston and spring will be in the air . . .

I've updated my movies of the pre-orbit observations of Ceres using Celestia (posted above). I had been using an older rotation model for Ceres and had been meaning to fix it, but I could never get the standard PCK file to work for Ceres. I ended up having to edit a PCK NAIF kernel file used for Saturn's moons, and basically broke Pallene, which did work before, in my installation in order to get Ceres to work. I also noticed that there is a difference in the prime meridian used by the IAU and the Dawn team/every other published map. I ended up just going with the Dawn team's meridian, so much easier that way (so I don't have to worry about correcting every map by 170 degrees.

For the curious, here's a zoomed in view of OPNAV1:

Click to view attachment

http://tucson.com/news/blogs/scientific-be...0cd46de206.html

Umm, is that what I think it is...?

If what you think it is involves the reflection of foreground ceiling lights, yes.

Just a little too small to read the date on the corner of the screen; would tell us whether that's from last week or this one...

Yes, ceiling light reflection, the new "OSIRIS munging".


Pretty sure it's the new ones.

Well, I would put it on par with Cassini's (and Huygens') coverage of Titan's surface and maybe even Messenger's global view of Mercury, but yes, most interesting "almost totally" uncovered new object.

I would say that even more interesting than the upcoming Pluto/Charon exploration. (sorry if I hurt someone's feelings... )

So, what's left after this year? Pallas, of course, and then Eris, Sedna... And yes, the (sub)surface of Europa!

Great era of exploration we are living in.

Some details can be seen in those images.


I lowered contrast a bit.

Plus 24 Themis! Kind of like a smaller Ceres (200 km diameter), covered in ice, and less than a degree off of our orbital plane. Should make at least a flyby en route to somewhere else a fairly easy thing to accomplish if it isn't deemed worthy of a mission of its own.

I was actually thinking the exact same thing the other day. I've since concluded that it's a bit hard to compare because of at least one icy moon of Saturn who is of a much larger size, namely Titan. The best pictures we had of its surface were made by Hubble due to Titan's opaque atmosphere, and they were of rather poor quality - basically showing Xanadu and not much else. Before Cassini-Huygens got close, it was still believed that a large fraction of Titan's surface could be covered by methane oceans, IIRC.

Still, Titan was very far from being the the sole mission target for Cassini, and it's also "just" a moon - still living with its parent.




Gah, that's kind of a cruel thing to do. They are ruining a part of the element of surprise while still not giving us something much better than what we had last week.


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While we wait for the full details of the latest images, here's a handy list for those who haven't seen it already (from here):

• Feb 4, 2015 | OpNav #3 | 148,000 km | 68 pixels | 2.2x Hubble resolution
• Feb 12, 2015 | Rotation Characterization #1 | 84,000 km | 116 pixels | 3.7x Hubble resolution
• Feb 20, 2015 | Rotation Characterization #2 | 48,000 km | 226 pixels | 7x Hubble resolution
• Feb 23, 2015 | Closest Approach | | Begin high-phase Approach
• Feb 25, 2015 | OpNav #4 | 39,000 km | 264 pixels | 8x Hubble resolution
• Mar 2, 2015 | OpNav #5 | 50,000 km | 205 pixels | 6.5x Hubble resolution
• Mar 6, 2015 | Capture| | Capture into orbit
• Apr 10, 2015 | OpNav #6 | 33,000 km | 300 pixels | 9.5x Hubble resolution
• Apr 15, 2015 | OpNav #7 | 21,000 km | 470 pixels | 15x Hubble resolution
• Apr 23, 2015 | Rotation Characterization #3 | 13,000 km | 20x Hubble resolution

thanks for posting this. it is useful to note that we get down to about 8x-HST end-of-Feb. then for another month we do a little orbital phasing dance with Ceres to get into the right place to enter mapping orbit (due to the safing event late last year). that means of course we won't get any better resolution again until April. That will give us all of March to chew on 250-pixels of Ceres . . .

New images are now available:

http://dawn.jpl.nasa.gov/feature_stories/D...DwarfPlanet.asp

The latest images have been posted.

http://dawn.jpl.nasa.gov/feature_stories/D...DwarfPlanet.asp

The bright(er) spot is still a mystery, I guess, and some crater candidates look more like craters than ever before.




EDIT: Actually...when looking at my monitor from a distance while it was showing this animation, I noticed that there are what looks like white patches to the right of the bright spot, in the same hemisphere.

And here is the NEW Ceres !!!
Left : taken by the Hubble Space Telescope in 2004. Right, taken by the Dawn spacecraft in 2015 (yesterday from 237,000 kilometers)...
with a quick processing I've done for you... It looks like a "bumpy" world.
Enjoy

Click to view attachment

Very clear craters in the new images. What I'm finding particularly interesting is the multi-ringed appearance of the two large adjoining basins (presumably craters) at the bottom, where it progresses from a light color at the center, to a dark ring, a lighter ring, and finally an outer ring which appears to be the basin rim. The dark inner ring appears not to be a topographic feature. The left basin in particular shows a hint of a central white spot similar to the bright feature in the upper portion of the image. I seem to also be seeing hints of grooves, with a major one in the bottom-right, arcing from lower left to upper right, and I'm pretty sure the two big lower basins are crossed from left to right by an even broader groove. I get a sense that we're seeing hemispheric asymmetries in terrain, with the lower portion having rather a lot more topography than the upper portion, but this may be due to seeing more of the terminator there.

I'm presuming up is north and down is south?

Can't wait til the next pics

Edit: Incidentally, what's up with the apparent Moire pattern in the animation?

Yep, north is more or less up.

PSI has another page up about the new OPNAV images:

http://www.psi.edu/news/opnav2ceres

They note that there appear to be topographic depressions associated with the two main, southern hemisphere dark regions with ribbon-like features extending from each of them. I would be a little careful about interpreting those ribbon-like features too much from this dataset. Could be canyons... could be just a random "chain" of impact craters.

Just a result of upsizing the original images -- you're seeing pixel boundaries, and your brain really wants those to be moving lines. Also looks like the interpolation algorithm tried to make hard boundaries of those pixel boundaries edging into Ceres' disk.

@elakdawalla:

Yes I found this upsizing to be annoying even before reading your post. This is a perfect example when a larger processed image isn't better.

The comparison image presented by vikingmars is ok though, thank you for posting.

And yes, looks a bit bumpy, have Ceres been battered so hard that it have gotten some cracks in the surface or is that something else we see a hint of?
The superficial similarities to some moons of Uranus have gotten stronger, those could be features similar to what have been seen on Ariel and Titania, well lets wait for the next set of images, I guess this only have wetted our appetite for more and sharper ones. =)

Here's a set of processed versions of the GIF frames (each one is a composite of three frames, merged, reduced in size, sharpened and contrast-adjusted)

Phil

Click to view attachment

nicely done phil. i suspect some linear features are present to the south, and definitely a cuspate ridge. could be a tectonic trench ala Ithaca Chasma on Tethys, but we have been fooled at these kinds of resolutions before, so I'm not placing bets just yet.

I'm beginning to come of the opinion hat the "dark ribbon" feature leading from what now appears to be the prominent southern basin to the west to a second, smaller basin is an albedo feature. It is too far south of the apparent basin rims to be a simple shadowing, and doesn't completely follow the basin rims. Also, if it's shadowing, it seems to be from some type of central peak units rather than from the rims, and stretches across the rims between two basins, which I wouldn't expect even complex central peak or ring structures to do. And, finally, it doesn't seem to be discontinuous as it tracks between the two basins or north-west to the "Y-shaped" bifurcation. (These details are visible, if barely, in the Hubble images, as well.)

Of course, this could be the "Martian canals" effect, where fuzzy unresolved details seem to grow into continuous linear features by dint of the mind's eye. I mean, it could be a chasm feature that has penetrated and degraded the basin rims -- after all, in some of the recent images, it's extent almost makes it look like a crack in the world defining an off-equator circumferential chasm system.

The one statement anyone can make for certain is that we'll know far better in a few weeks.

-the other Doug

Can spalling occur on a body this large? From Phil's versions, the ringed terrain has the appearance of being popped out rather than filled with the usual slumped regolith. I'm prepared to be surprised and corrected with each update of resolution and context, but had to at least muse about processes that create hollows.

Comparison of the HST map (note it's recentred here to avoid splitting the Dawn map area) and a cylindrical projection of the three images I posted earlier.

PLEASE note that my registration is not well controlled, and you really have to wait for the Dawn team to produce an accurate map. This is just to indicate roughly what a map might look like when we do get one.

Phil

Click to view attachment

Probably superficial, but with its bright spot and dark, presumably cratered (at least where we're looking) surface, I'm having flashbacks to Umbriel (in the attached image, Ceres is on the left, Umbriel on the right).
Click to view attachment

Wow, that's pretty spectacular similarity

That bright spot on Umbriel in that frame is the circular feature at the top in this image, right?

yeah. too bad we never got better on Umbriel or we could test that hypothesis...

Perhaps this is an indication that Ceres formed beyond the snow line?

Whenever an interviewer asks me what mission I want to see next, I always say I want a Uranus orbiter. I want to see those moons up close, and study that ring system. Uranus needs more advocates.

Here's Ted's best work on Umbriel.

Morpheus, we know Ceres as a substantial amount of water; could even have an ocean. Water ice is not stable over the long term over most of its surface except near the poles.

I made this gif animation by adding same frames in reverse order after the last frame in the original, so that Ceres rotates back and forth.
I find it much easier to spot different surface details this way.

Ceres rotating back and forth

I'm getting closer to believing those linear markings are real!

Whatever else resolves as we get closer, the theory that there would be no surface relief, just albedo differences, except at the poles because of Ceres' fairly high temperature seems to be dead.
Which presumably says something about the near surface composition not being generally icy (a really thick lag?).

P

One possibility, which wasn't considered very likely, is that Ceres' crust is undifferentiated -- that the crust never heated enough to change from its primordial mix of ice and rock. The reason that this is unlikely is that if Ceres' interior has differentiated (and it almost certainly has), then you'd have the situation of a denser crust above a less dense icy mantle, which is unstable -- you'd expect the crust to founder into the mantle in that situation.

It really is. Somebody should pass on a tip to the right people.

The ideas of Phil and Toma B combined, stretched:

I've taken the average of two consecutive images to reduce image noise, but to avoid too much motion blur, allowing for some non-linear brightness stretching.
The stretching suggests higher specularity than real, but it hopefully shows features a bit more distinguished.
The apparent huge linear features make me think of Europa and large rift valleys on Earth, i.e. of tectonic features. Plate tectonics on a water basis instead of magma would be a thought I could get used to.

I'm not up to speed on Ceres literature and I suspect a lot of other readers won't be. Can you remind us why the interior has almost certainly differentiated?

And while I'm here I'd like to add my thanks to Toma B. I agree with Habukaz - it really does help.

Here is a stack of 9 images from the new January 26 images, corrected for Ceres' rotation. I used the last 9 images from the rotation movie. The image processing is very similar to what I did earlier with the Januar 13 images, a linear contrast stretch followed by an unsharp mask.

Click to view attachment

This is getting curiouser and curiouser. The southern hemisphere now looks even more interesting and I don't think albedo variations are a big factor there. I also notice hints of long linear features with roughly a NW-SE direction; I'm pretty sure they are real.


Some time ago Uranus also became my absolute #1 target I'd like to see visited by a spacecraft mission (preferably an orbiter). It's well above my #2 target and I strongly agree that it needs more advocates.

I am also seeing a lot of ridges.. maybe smoothed out due to warmer ice on Ceres surface?
And is the bright spot really that bright or is that an imaging artifact?

Also vote for Uranus mission!

Craig

I don't know how it would be possible, but the visual impression I now get from the animations is of a rift valley separating the upper and lower hemispheres. Do any of the ice mantle scenarios make plate tectonics possible?

Still fixated on the bright spot. Know the image processing to bring out other more subtle features would enhance it but. Really is bright compared to surroundings.

This I so cool fellow space friends. A big thanks to the DAWN team for providing the images so quickly! What a ride!

Craig

I absolutely agree with Bjorn and bellaraphon1 and MarsInMyLifetime, and take back some of my earlier comments about the "dark ribbon." It really looks like a very wide chasm system running from southeast to just south of due west, starting out the width of what looks like a large impact basin but stretching on, either the crater chain of all crater chains or an actual rift valley the likes of which dwarf even those on some of the Saturnian and Uraniun icy moons we've seen.

I'm almost brought to mind, looking at the terrain that begins to peek out from around the right horizon, of a massive disruption of the planet and re-assemblage of the chunks in somewhat random orientations. Ceres also looks a lot lumpier, i.e. non-spherical, and to a greater degree, than I would have thought.

But, again, we'll know better very, very soon.

-the other Doug

I gotta think the bright spot is an extremely fresh crater into an ice layer. Maybe not that old, either -- to escape the darkening effects of solar radiation and small impactors and be that relatively bright, we could be looking at a feature formed in the last few millennia, if not centuries.

The next question is whether or not the entire crust is basically ice, or something else with pockets or discontinuous layers of ice. That could explain why an impact in one location would be super-reflective while one only a few hundred km away is not.

-the other Doug

Does anyone have the feeling that within a few months there is going to be intense discussion here (and elsewhere!) about lander missions, and where to send them?

Seems to be indications of smaller bright spots. Could large impactors punch through several kilometres of dark lag to expose fresh ice, which then as the other Doug suggests, darkens over time?

P