Dawn's first orbit, including RC3, March 6, 2015- June 15, 2015 Options

[Ron Hobbs]

Dawn is now officially in orbit around (1) Ceres!

Congratulations, NASA. Nice images of crescent Ceres.

NASA Spacecraft Becomes First to Orbit a Dwarf Planet

[elakdawalla]

I thought it was time for a new thread, now that Dawn's in its first orbit. We can look forward to a couple more op navs, on April 10 and 14, and then RC3 later in the month. Use the previous thread for up to Op Nav 5; let's use this thread for Op Navs 6 and 7 and RC3 and then we'll split again once Dawn reaches its first survey orbit.

[DrShank]

I thought it was time for a new thread, now that Dawn's in its first orbit. We can look forward to a couple more op navs, on April 10 and 14, and then RC3 later in the month. Use the previous thread for up to Op Nav 5; let's use this thread for Op Navs 6 and 7 and RC3 and then we'll split again once Dawn reaches its first survey orbit.

thanks emily!

i noticed in a prior thread that it said mapping starts in July. thats a bit of a misnomer as mapping starts in Survey Orbit in May (and one can count RC3 as a global map, at about 1.5 km resolution, which is comparable to much of Voyager at Saturn.) wows!

[Habukaz]

What should nonetheless be correct is that a new mapping phase starts in July, namely HAMO; and that this is still the month New Horizon zooms past Pluto.

[Sherbert]

What should nonetheless be correct is that a new mapping phase starts in July, namely HAMO; and that this is still the month New Horizon zooms past Pluto.

Also the time when the fireworks on 67P are expected to really start.

[ChrisC]

From http://www.nasa.gov/press/2015/march/nasa-...ly-enter-orbit/ :

NASA will host a media teleconference at 2 p.m. EST today [Friday] to discuss the historic arrival of the agency’s Dawn spacecraft at the dwarf planet Ceres. ... Participants in the teleconference will be:
- Jim Green, director, Planetary Science Division, NASA Headquarters, Washington
- Carol Raymond, Dawn mission deputy principal investigator, Jet Propulsion Laboratory, Pasadena, California
The teleconference will be streamed live on NASA’s website, at: http://www.nasa.gov/newsaudio

Does anyone know if a recording of this telecon exists? Normally, at the end of a NASA telecon they offer a number that you can call into to hear it again -- inexplicably, they only offer that number DURING the call itself. Also, JPL will sometimes take the audio and make a video out of it (synced with slides if there are any) and upload to the Ustream or Youtube account.

Or was there absolutely nothing of interest said during the telecon, just the usual recapping of what's happened?

Thanks!

[Gerald]

Link to the recorded "Dawn Ceres Arrival" briefing.

[ChrisC]

Link to the recorded "Dawn Ceres Arrival" briefing.

Thanks but that's the PREVIEW briefing, that aired on NASA TV on Monday. I'm talking about the teleconference (media phone call) from Friday.

[anticitizen2]

Searched for it on YouTube:

https://www.youtube.com/watch?v=Qk0Cr0Z13hc

Edit: finally had a chance to listen to it - nothing new was said, really.

[TheAnt]

Also the time when the fireworks on 67P are expected to really start.

And Voyager 2 might break out into interstellar space at about the same time also. The values for the interstellar >70 MeV protons have been slowly climbing to the same value as for V2 - though if the current trend holds it might happen a few months later.

[ChrisC]

Searched for it on YouTube:
https://www.youtube.com/watch?v=Qk0Cr0Z13hc
Edit: finally had a chance to listen to it - nothing new was said, really.

THANK YOU!!!

[peter59]

It must be an unusual sight. The narrow sickle of Ceres with constellation of Orion in background.

[Mr Valiant]

It must be an unusual sight. The narrow sickle of Ceres with constellation of Orion in background.

Thanks Peter,
just dipped outside for a look and there is Orion, laying in the west. Go Dawn.

[Gladstoner]

It must be an unusual sight. The narrow sickle of Ceres with constellation of Orion in background.

Thanks. That certainly puts things into perspective.

[marsbug]

It must be an unusual sight. The narrow sickle of Ceres with constellation of Orion in background.

Oh my, talk about making the familiar unusual....

[Malmer]

I like these perspective jolting moments. My absolute favorite is earth and the moon seen from mercury during the lunar eclipse.

[Habukaz]

Dawn is currently communicating with Earth. Here's hoping for some of spot(s) 5.

http://eyes.nasa.gov/dsn/dsn.html

[JohnVV]

for those interested this is the orbit for the Dawn spacecraft as in spirals down to a lower orbit over the next few weeks



the red line is the spacecraft orbit
generated from the
dawn_ql_150219-150531_150415_v1.bsp
dawn_ref_150423-150704_150414_DA400_v1.bsp

naif kernels

[belleraphon1]

Dawn Glimpses Ceres' North Pole
http://dawn.jpl.nasa.gov/news/Dawn_glimpse..._north_pole.asp

[elakdawalla]

JPL has released an animation of the April 10 opnavs. Very cool



On Twitter, Brian Wolven asked me if the prominent bright peaks seen at the right-hand limb at the beginning of the animation were the two bright spots. I tried to figure out the answer to that, but couldn't. I made the attached polar projection of the northern hemisphere of the DEM from JohnVV's map, but I couldn't match crater features.

Attached thumbnail(s)

 

[JohnVV]

it would NOT be visible YET in the April 10 images

it is at 20 deg North
what is visible in that gif is 50+ to 90 north
as you can see in these two screenshots ( if the naif kernels are accurate, i have been having MAJOR issues with some of them )
added extra light to the scene
-- FOR APRIL 10 like the gif--
near the center

- off to the right side of ceres

[Habukaz]

Pleasantly surprised to see that OpNav 6 was released today. Something odd happens when I try to extract the individual frames with IrfanView, though: the frames come out in all sorts of sizes. (edit: never mind, Python to the rescue)

In the latest Dawn Journal, it was mentioned that spot(s) 5 would not be visible in OpNav 6:

As we describe below, Dawn’s extensive photographic coverage of the sunlit terrain in early May will include these bright spots. They will not be in view, however, when Dawn spies the thin crescent of Ceres in its next optical navigation session, scheduled for April 10

so I think it would be odd if they suddenly turned up anyway.

[elakdawalla]

it would NOT be visible YET

Thanks for those simulations, they are really helpful.

[JohnVV]

in the northpole image you posted the two side by side bright spots are the line here circled


and it will be visible TODAY but not much better than before. just from a different angle

[Gladstoner]

I think this mound (or mounds) in the large crater is a good candidate for the limb peaks:



Note the trio of craters circled in red:




They seem to correspond with the craters in red here:



Now extend a longitudinal line over the north pole here:



And here (north pole marked with 'N'):



The peaks are to the east of the line. The crater with the mound(s) is marked with a yellow box on the longitudinal map.

[Gerald]

With the following assumed globes for PIA19317.gif OpNav6

I've obtained these projections:

Addition of the projections to the DLR map from RC2:


The bright spot is probably just outside frame 20 of the sequence.

[JohnVV]

aligning the animated gif with the textured mesh and lat long marks

the other "bright spot" is at 42 N and 0 long.
it is barely visible in the gif
3 frames from the gif with and without a spherical grid
the 0/360 long is top right on the sphere and you can see the major bright spot

hidden under the horizon

almost visible on the top left

[Toma B]

Ceres rotating back and forth in latest images from Dawn spacecraft.
I find it much easier to spot different surface details this way.

[TheAnt]

I find it much easier to spot different surface details this way.

Thank you for your effort Toma. Now this make me think the surface resemble a golf ball. =)

[mcgyver]

Ceres rotating back and forth in latest images from Dawn spacecraft.
I find it much easier to spot different surface details this way.

I can't figure out if bright spot is visible in the animation.
I place here the other available images for more comfortable comparisons:
http://cdn.phys.org/newman/csz/news/800/20...warfplanetc.jpg
http://cdn.phys.org/newman/csz/news/800/20...hisimageist.jpg
https://lightsinthedark.files.wordpress.com...3/pia189231.jpg
http://www.jpl.nasa.gov/spaceimages/images...19056_hires.jpg


I don't understand if I must link them or upload them or insert them in tag so I just add the links.

[djellison]

I can't figure out if bright spot is visible in the animation.

It isn't.

[ZLD]

Im rather curious about these two spots that appear in frame 6 and frame 7. Not necessarily from spot 5 but in the same vicinity. They are somewhat dim and on the left lim.

[JohnVV]

ZLD - your map is upside down

That is the two side by side spots that are at 20 degrees NORTH and 240 degrees longitude and is visible in the added light 3d graphic I posted here of the two recreations that show where it WOULD be IF it was lite

http://www.unmannedspaceflight.com/index.p...st&p=219593


you can see in the first image ( added extra AMBIENT light ) to the 3d rendering

[Gladstoner]

JohnVV, thanks much for the simulations with the grids. They really help to put things into perspective.

Also, have you yet added the grid to the global cylindrical map?

[JohnVV]

the grid is dynamically added in the 3d program i am using .

Ceres's orbit is calculated using the JPL orbit data and Dawn's orbit is also calculated using it's orbital data the same data that the research scientists are using the naif kernels.

As to the map. The map posted is 0 long to 360 long ( 180 in the center ) a grid could be added ? but not really needed this very EARLY map is very low resolution 1024x512 pixels and the poles ARE MISSING.

In comparison the published Vesta map is 48 ppd ( 17,280 X 8,641 ) pixels .

[Habukaz]

Is the dimmest bright spot resolved in the OpNav 7 images? It looks distinctly elongated in all frames where it "glows":

[djellison]

Is the dimmest bright spot resolved...

The accompanying press release text clearly states

"The images show the brightest spot and its companion clearly standing out against their darker surroundings......"

[Habukaz]

I don't see how that implies that they are resolved.

[centsworth_II]

Is the dimmest bright spot resolved....

Are you asking if the impression that the elongated spot is split up into three parts can be trusted? Looks like it to me, but you know what my opinion's worth!

[Habukaz]

Just noting that it looks like it spans more than one pixel at this resolution (and also that it looks elongated from this vantage point). Looking a bit more closely at the images, it seems almost certain to me that it is resolved; but I haven't seen any relevant comments from the science team.

[JohnVV]

from the tiny gif that is PIA19064

it is looking like the one bright spot at 0 long.( 360 long.) and 42 North

is in fact ejecta from a crater ( i am GUESSING that the OTHER side by side bright spot at 240long and 20 North are ALSO ejecta)

4x enlargements from the 8 bit INDEXED gif

[StarryKnight]

The surface between the craters looks very smooth. The smooth areas between craters may only appear that way because of smaller craters can't be seen due to the low resolution of the current set of images. But, so far, there does not appear to be mountains or ridges between the craters.

Also, when I imagine a generic crater, say on the moon, I think of the surrounding of it sloping up fairly steeply then the surface dropping sharply as you go into the crater. But I don't see much of a rise on the outside edges of the craters. Are these craters really that smooth or does it look like that because the resolution or sun angle in these images? If they are really that slightly sloped on the outside, could it be because of what might be below the surface or

[JohnVV]

do to the fact that Ceres is very high in ices the craters have flat bottoms and are shallow

the one in the crops i posted looks to be on one of the ridges and came in at a very shallow angle

some of the "smoothness "is do to the 4x enlargement and that the original crop was only 128 px on a side ( rather small)

keep in mind that the spacecraft is NOT YET even in a near circular orbit YET
and this set of images is from April 14/15 -- LAST WEEK

[TheAnt]

Looking a bit more closely at the images, it seems almost certain to me that it is resolved; but I haven't seen any relevant comments from the science team.

Yes I tend to agree thinking its resolved or nearly so on the first image of the sequence, but on the subsequent images it seem to get saturated and float into adjacent pixel areas -and so larger than it actually is -again


Edit: It's not the first, but frames 8 and 9, the page loaded to slow so I missed the early part of the rotation sequence, but I did separate the images after the post to find out.

[Toma B]

Back and forth animation made using grabbed frames from 20 frame gif.

All 20 frames separated into .png images on Dropbox.

[scalbers]

Yes I tend to agree thinking its resolved or nearly so on the first image of the sequence, but on the subsequent images it seem to get saturated and float into adjacent pixel areas -and so larger than it actually is -again

The linear arrangement almost has the look of the "Voyager Mountains" on Iapetus...

[ZLD]

Performed some slight enhancements on frame 10 of the PIA19064 animation. Cropped, luminance adjustment, deconvolution and scaled 200%.


And again with frame 11.


These are stretched until the bright region is slightly below max saturation.

[Gladstoner]

The bright spot seems to be less prominent when on the morning terminator than on the evening. One possibility is that much of the bright material is on a west-facing slope.

[dudley]

Dr. Chris Russell, principal investigator of the Dawn mission, indicated in an e mail today to NBC News that even at the current resolution (1300 2100 meters/pixel) the bright spots were not resolved. This will presumably necessitate a marked revision upward of the albedo of the spots, which was set a minimum of 40 percent, based on the previous resolution of 3.7 kilometers/pixel.
NBC News Article

[Explorer1]

The fact that these things were visible from Earth still blows my mind. How small would they have to be before we get in the range of an Enceladean albedo?

[Gerald]

Assuming the globes

here a forward/back animation (1200 pixels) of rectangular roughly map-projected versions of the 20-frames OpNav7 sequence PIA19064.gif, aligned to the DLR RC2 map:

(NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/"Gerald")

Album of individual projected frames (1440x720 pixels).

[dudley]

The fact that these things were visible from Earth still blows my mind. How small would they have to be before we get in the range of an Enceladean albedo?

Well, it appears that the ratio of an area 3.7 kilometers in diameter to one that is 1.3 km across is about 8.1 to 1. I'm assuming that albedo is inversely proportional to reflective area. If I'm not mistaken, one could multiply the old albedo figure of 0.4 by the 8.1 ratio to get the minimum new albedo.

[Gerald]

Albedos greater than 1.0 are very rare in nature.

... Forth-back animation of polar projections of OpNav7 (same globes assumed as above) :


Album of individual 1440px maps.

[alk3997]

The bright spot seems to be less prominent when on the morning terminator than on the evening. One possibility is that much of the bright material is on a west-facing slope.

If this were a geologically recent active region, wouldn't a reasonable expectation be that the crater floor is smooth as the material flows or falls onto the floor? It's hard to tell whether the crater floor in the zoomed-in version is itself cratered or those are image processing artifacts.

My money is still on a shallow angle impact causing the center bright spot with a secondary impact causing the second spot. It also explains the variability in brightness between different viewing angles.

Andy

[fredk]

Dr. Chris Russell, principal investigator of the Dawn mission, indicated in an e mail today to NBC News that even at the current resolution (1300 meters/pixel) the bright spots were not resolved.

It probably depends on exactly what you mean by "resolved". There's certainly not much detail visible in both of the two spot 5 subspots, but I would call them "resolved" in the sense that they are clearly larger than the PSF. Both of the subspots are elongated, and the orienation of elongation rotates with Ceres. This means the elongation can't be due to bad optics (eg, astigmatism) and almost certainly not due to motion blur during the exposure. Similarly, it is extremely unlikely for pixel noise to conspire to produce elongation in both subspots rotating consistently with Ceres's rotation, even though we're looking at only a small number of pixels here (ie, S/N looks good judging from frame-to-frame consistency).

It appears that the fainter subspot (upper in my animation below) is composed of two "sub-subspots" (again, the consistency from frame to frame argues against pixel noise). The brightest subspot (lower in my animation) perhaps also consists of two sub-subspots, the lower of which appears first and the upper which brightens. As others have pointed out, these sorts of brightness variations could be simply due to variable geometry of exposed surfaces/shadowing.

[Gerald]

I'd assign the apparent split of the fainter spot to a more or less concentrical topographical feature in the crater. So it's not necessarily an albedo feature, but possibly an "inclination" feature.

[fredk]

But the upper double spot only brightens as you go from frame to frame. If the dark gap between the two sub-subspots was due to inclination, the dark gap should have been more prominent in the earlier frames when the illumination angle was lower.

Of course the real problem is that we're arguing over only a few pixels here. One way to improve things while we wait is to note that the spot 5 crater remains at roughly the same distance from the limb in all the frames, ie we're roughly "looking straight down at the north pole". So the viewing geometry for the crater is roughly constant. So someone could usefully do a poor-man's superresolution by enlarging (say 4x), rotating, and then stacking the images...

[dudley]

It probably depends on exactly what you mean by "resolved". There's certainly not much detail visible in both of the two spot 5 subspots, but I would call them "resolved" in the sense that they are clearly larger than the PSF.

I recall when only one bright spot was discernible in this crater, then there were two. There was apparently no claim that the spot had been optically resolved at this point. When Dr. Russell says that the spots are not resolved because they're too small, I'm inclined to rely on that, given his expertise, and knowledge of this particular situation.
It does not appear to me that the brighter of the two spots is even separated into two distinct parts, which seems to argue against any reasonable definition of the word 'resolved'. The variable lighting of portions of this spot could have any one of several explanations. The bright spot sometimes appeared to be elongated in the images, long before there was any thought that it might be optically resolved.

ADMIN NOTE: Everyone - I think that we can drop the discussion over the word 'resolved'. You can go into the 'micron' scale and still not fully "resolve" an object. Let's just wait for better images that will help to identify the nature of these features. Not long now.

[JohnVV]

The bright spot seems to be less prominent when on the morning terminator than on the evening. One possibility is that much of the bright material is on a west-facing slope.

as one can see in the second attached image in post # 41


it is on a west facing slope


as to the other one
WE WELL SEE --- once there are better images

[dvandorn]

In the previous image, and also in the animations showing this region, I'm tempted to say that it's not ejecta that's so bright. This "spot" is resolved to the point that, when not saturating the ccd's, it looks like a pyramidal structure (in shape, not at all suggesting it was artificially constructed) that is definitely lighter in color than the surrounding terrain. It doesn't exactly follow the curves of the crater wall it seems to overly, either.

I'm wondering if this could be a constructional landform -- looks a little like a volcano-like structure in this image, at any rate.

Boy, it'll be nice to get better pictures of these areas. Patience... I must learn patience...

-the other Doug

[Webscientist]

The linear arrangement almost has the look of the "Voyager Mountains" on Iapetus...

Well found for the analogy Scalbers!

I've extracted a portion of the Voyager Moutains and the bright patch of Iapetus, about 5 km long, looks like the bright spot of Ceres... to a certain extent!

Attached image(s)

 

[Gladstoner]

The brightest subspot (lower in my animation) perhaps also consists of two sub-subspots, the lower of which appears first and the upper which brightens. As others have pointed out, these sorts of brightness variations could be simply due to variable geometry of exposed surfaces/shadowing.

That animation really helps.

I'm seeing (imagining) something along these lines:



The main bright area seems to be in the western part of a little depression of some kind, with the brightest material not becoming visible until the shadow clears the slope.

(Nothing in the drawing is necessarily to scale; plus, I intentionally left out the other bright spot(s).)

[elakdawalla]

Here's a slightly different take on this sequence of images. (Click to enlarge)

[Ken2]

A heavily zoomed and exposure enhanced version of the first 3 frames of the bright spot. (this may have introduced artifacts - but overall it allows a better overall visualization IMHO)

I think the these frames clearly show the outline of a crater with the far wall getting the first bit of sunlight. As the sun rises in the crater the crater gets more and more illuminated causing pixel saturation and bleed for the subsequent not shown images, but roughly corresponding to the crater dimensions.

[click to animate the GIF]

[ZLD]

Is there any speculation on what would be able to leave such a smooth, shiny depression? To me, it appears that much of the crater may be a similar make up because as the sun angle decreases, the crater continues to light up. Seems to be smack dab in the middle as well. Possibly a remnant of some cryo-gyser sort of blow out maybe?

[JohnVV]

well as of the 19th
the Dawn spacecraft would have gotten a good view of the area


and today the 21st

[Gerald]

...So someone could usefully do a poor-man's superresolution by enlarging (say 4x), rotating, and then stacking the images...

PIA19064, 4x magnified (probably bicubic), then polar-projected (bilinear interpolated) to 2880x2880 pixels, then cropped and registered, then pairwise averaged (stacked), sharpened, forth/back animated:

[Gladstoner]

Is anyone else having issues with the released animated GIF not repeating/looping?

( http://dawn.jpl.nasa.gov/news/Ceres_bright...k_into_view.asp )

[Gerald]

Yes, with (outdated) Windows XP / Chrome, at least.

[PaulH51]

Yes, with (outdated) Windows XP / Chrome, at least.

Also the same with W7 / Chrome

[JohnVV]

it is a setting ON!!! the dawn web site !

THEY!!! have the gif set to "run once"

[nprev]

Yeah, must be. I had to clear my cache to get it to run again. Hopefully this will be noticed and corrected soon; meanwhile, let's all be patient.

[fredk]

Works fine (even on ancient xp) if you download the gif and play in, eg, irfanview.

[elakdawalla]

I edited it to loop forever (click to enlarge):

[Mr Valiant]

Emily, great input. Like everyone here, hanging out for the hi resolution pics.
Anxiety level akin to Huygens.
We may actually be seeing a steady `volcanic eruption`.

[dudley]

It's said that when Dawn's mission is finished, they'll park it permanently in orbit of Ceres. A good thing they won't have to feed coins to De meter.

[nprev]

...aaaand, Dudley's banned.

[Mongo]

...aaaand, Dudley's banned.

That was a joke, Ceres is the Roman equivalent of the Greek Demeter.

Unless you were also making a joke about making puns on this thread. I guess the smiley was a clue.

[tedstryk]

That was a joke, Ceres is the Roman equivalent of the Greek Demeter.

Unless you were also making a joke about making puns on this thread. I guess the smiley was a clue.

It is rather unforgivable

[dudley]

It's just that I feel it's important to get some pun out of life!

[Holder of the Tw...]

Looks like the Dawn website just underwent a major overhaul...

dawn.jpl.nasa.gov

At first glance, I can't find where the "Where is Dawn now" simulated views have gone.

[StarryKnight]

Yes. It looks like they've changed the user interface to be more tablet friendly, as many web sites are starting to do. Unfortunately, my primary web access (at work and at home) are desk tops, which aren't as user friendly as for these tablet friendly sites.

The "where is Dawn now" can be found by selecting the Menu button, then clicking (or tapping) on Mission. About a quarter of the way down the Mission page, you'll see "Where is Dawn now?" followed by a link labled "> View". Or you can just use this link here: http://dawn.jpl.nasa.gov/mission/live_shots.html

[JohnVV]

all this "portrait" formatting on LANDSCAPE 16X9 screens !!!
( a TON of sites are doing this so...)

makes one REALLY WANT some of the by-gone days of what sites USED to look like

CODE

w3m http://dawn.jpl.nasa.gov/

nasa.gov 1996
http://web.archive.org/web/19961231235847/...//www.nasa.gov/

[Phil Stooke]

I really don't like this new trend. It's a fad among web designers - like the one a year or two ago where everything on the screen would flash and shake as the cursor moved over it. The most basic principles of good design are being thrown out of the window, mainly because designers need to keep changing sites or they are out of a job.

If UMSF goes the same way I'm quitting! Or at least I would if there was anywhere else to go.

Phil

[MichaelJWP]

A shame we're reduced to discussing website design, interesting though it is. I too prefer pages rather than the scroll-for-ever sites of today.

Anyone have any idea when we might see the next images, presumably there are some great shots since getting into orbit that we're not seeing yet?

[djellison]

The most basic principles of good design are being thrown out of the window, mainly because designers need to keep changing sites or they are out of a job.

I can't stand this shift to 'trendy' websites either....but I have had visibility into the process behind the redesign for many of JPLs pages...and I can tell you, the demand for it isn't coming from designers, it's coming from management.

And when it's winning awards all over the place - it's not going to go away any time soon : http://www.jpl.nasa.gov/news/news.php?feature=4566

[JohnVV]

with this getting off topic

i think most of us HAVE recently unbookmarked sites we used to use
Do to the now "handheld TELEPHONE !!!! " trend

but on a but of a different note
i DO find that the MOST useful sites ( content wise) look like this



a FTP page for the dawn spice kernels

[Habukaz]

New RC3 image is out at the photojournal: http://photojournal.jpl.nasa.gov/catalog/PIA19319

Think it might show one of the interesting big craters near the south pole?

[Habukaz]

Following up on that image, is the relatively crater-free area above the crater in this crop part of a massive landslide? Have we observed something similar on other bodies?



The crater floor also appears to be of a relatively young age.

[dvandorn]

It looks more like a massive ejecta sheet to me, and we do see those commonly on our own Moon. They are most often seen, on the Moon, as ejecta from large basin impacts. As a comparison, take a look at the Fra Mauro formation on the Moon's near side.

In fact, this resembles that kind of structure quite a bit.

-the other Doug

[Gladstoner]

Since we're on the subject of website design trends/fads, I'm not fond of the 'load more'- or 'fetch more images'-style of display. After awhile, the browser chokes and dies before all thumbnails, posts, etc. can be viewed. Two examples of this on well-known sites:

https://www.flickr.com/search/?q=ceres%20dawn

https://instagram.com/marscuriosity/

I guess I'm old fashioned, but I don't mind having to click 'page 2' to see the next 50 image thumbnails.

At least the image display formatting on the Dawn site is still 'old fashioned'.

---------

Ok. Back on topic:

That modified terrain around the large crater is intriguing. It does look like fresh ejecta, but from where?

[stevesliva]

I can't stand this shift to 'trendy' websites either....but I have had visibility into the process behind the redesign for many of JPLs pages...and I can tell you, the demand for it isn't coming from designers, it's coming from management.

I'm reminded of the old issue where webpages would break if they detected you were on a phone:
https://imgs.xkcd.com/comics/server_attention_span.png

... now they apparently will just assume so.

[Bjorn Jonsson]

...i DO find that the MOST useful sites ( content wise) look like this
a FTP page for the dawn spice kernels

Yeah - I usually get happy when I find something like this (SPICE kernels, IMG files or stuff like that).

Following up on that image, is the relatively crater-free area above the crater in this crop part of a massive landslide? Have we observed something similar on other bodies? The crater floor also appears to be of a relatively young age.

I'm not sure about landslides outside of craters (and this may or may not be a landslide, it will be very interesting to see higher res images of this terrain) but of course big landslides inside of craters are quite common, for example I remembered this one on Iapetus: http://photojournal.jpl.nasa.gov/catalog/PIA06171

[volcanopele]

Reminds me a lot of the terracing on relatively fresh, large lunar craters like Tycho, so the stuff above it could be ejecta.

[elakdawalla]

It really does look strikingly lunar.

[Phil Stooke]

I can't say that area above the crater looks like a landslide to me, but if it is, there is a very good precedent. Look at the lunar farside crater Tsiolkovsky... on its northwestern side, a massive and clearly delineated landslide or debris flow extends down into an older crater.

Phil

[pitcapuozzo]

Another view of the southern hemisphere! http://photojournal.jpl.nasa.gov/jpegMod/PIA19321_modest.jpg

Attached thumbnail(s)

 

[Gladstoner]

Compared with the north polar area, there seems to be a paucity of small to medium sized craters, but more larger craters.

Perhaps the viewing angle due to Dawn's closer proximity may have something to do with it.

[fredk]

More puzzling image release quirks: PIA19319 is reflected, as you can see by comparing the two new releases:

[djellison]

More puzzling image release quirks: PIA19319 is reflected

I don't see reflection between those two images.