That black material on the surface - could that be from carbonaceous chondrites? Those look like they could be dark enough.

These are the ones, currently in their science (imaging) missions, that I am aware of. I am not sure about the other Mars missions, the Lunar missions, etc.

CLASS 1 : Releases all imaging products immediately

MER
Cassini

CLASS 2 : Releases one image per day

Messenger
DAWN

CLASS 3 : Known to be taking images, but no regular releases

All the ESA missions?

How many of these are in their initial science phase vs. consolidated or extended science phases?

Cassini, MER, and Phoenix were releasing raw images to the public during their initial science phases.

I fear we're going round in circles here. Heels have been dug in. If they were going to change policy they would have done so by now, but someone, somewhere, is simply determined not to release raw images out into the wild. Which is a great shame, and is wrong, and means the mission is losing out on a tremendous amount of interest, good will and public participation, but so be it. I think we'll just have to accept it now and make the best of what we're given. Which is going to be a lot, in the long run, but boy, what a wasted opportunity.

Mars Express VMC - within minutes of hitting the ground
Envisat MIRAVI - on the web daily.


stevesliva - Using the argument that other missions fall short, therefore it's just fine for Dawn to fall short isn't valid. They should all be stepping up to the plate and delivering as Phoenix did, and as VMC, Cassini and MER continue to do.

Don't forget New Horizons which released raw images during cruise phase. I'm not sure anyone else can say that...?

I am a US government grant supported scientist studying microbial genomes. My NIH grants stipulate that I make all raw sequence data available to the scientific community within hours. Biomedical research is just as competitive as the space sciences and we do just fine publishing our results ahead of the competition.
Scientists on the Mer, Casini and Phonex missions seem to have been able to publish their papers in Science and Nature without UMSF or other scientists scooping them. As a scientist who is highly competitive in US government supported research and who makes raw data available freely, I don't understandwhat the Dawn PI could be thinking. He clearly is not trying to follow in the footsteps of Steve Squyres or Carl Sagan. He clearly is not interested in public outreach or public support for NASA at a time when public support is dearly needed. He is not interested in helping young scientists jump in and use his data.
How unbelievably disappointing.

Floyd Dewhirst, DDS, PhD
Senior Member of Staff
The Forsyth Institute
Professor, Department of Oral Medicine,
Infection and Immunity, Faculty of Medicine
Harvard University

ZING!

"My NIH grants stipulate that I make all raw sequence data available to the scientific community within hours."
Interesting, I always thought, that planetary research is most open to anyone (not only scientific community).
It's nice to hear, that this openness isn't specialty of planetary research.

"Don't forget New Horizons which released raw images during cruise phase. I'm not sure anyone else can say that..."
New Horizons isn't ordinary space mission! It's miracle!

unless you count Phoenix's image of its soil scoop taken during cruise

If it really is once per day, where is today's image?

If they do as Messenger has done and have speedy PDS releases, I don't see a problem. I would like full raw releases as the images come in, but I can see the argument against it as well.

How about one image per Vesta day? *ducks and runs*

Science Survey Orbit is almost reached:
Click to view attachment
Now, Dawn is engine-off on almost circular orbit (taking navigation pictures?)... next engine burn could be the final one before "definitive" orbit insertion!

I too am a bit disappointed with the slow image releases, but because there is so much to take in with each new image, not to mention that the mission was almost cancelled -- twice, I'm happy that there is anything to see at all. After staring at the Hubble images for the past several years, I'm thrilled to see the smorgasbord of features and detail on this newly revealed, yet strangely familiar world.

(BTW, I'm not so sure I'll be the same if there is a similar policy with MSL. Having traveled to the American southwest 11 times in the last 20 years, I will probably have minor conniption fits if I have to stick to my imagination at Gale. For some of us travelers and hikers, its all about rolls and rolls of film -- and memory cards -- with thousands of photos....)

SOHO does pretty much constant releases, does it not count as a ESA mission (or because its not a planet mission)?

SOHO images are probably released quickly because solar activity potentially has economic consequences across the world and needs to be disseminated in a timely manner.

Also, the armchair comet hunters would complain....

http://dawn.jpl.nasa.gov/feature_stories/s...ence_orbits.asp
" That initial orbit of the rocky world Vesta begins Aug. 11, at an altitude of nearly 1,700 miles"

Mission Status, August 2, 2011

"Dawn Completes Spiraling to Survey Orbit"

MSL is being held to the policy established by MER. You can start your drooling now

I was thinking the other day that it would be interesting to try to actually quantitatively analyze the impact of releasing all raw images vs releasing one image a day vs releasing basically nothing except in occasional press releases. All three methods are being used. I've heard the argument before that releasing too many pictures blunts the impact of occasional releases. I know how we all feel about that argument; but I don't know of anyone who's tried to examine and quantify the amount of attention a mission receives and correlate that with their frequency of press releases and image releases. Scientists do (or at least should) respond to data. While I would like to believe that the data would show a greater impact correlating with greater openness with data, there's always the possibility that I'm wrong about that.

This might be easy to check.

Next time you give a talk (museum, library, schoolroom, general outreach):

"Show of hands, how many people have heard of the Mars Exploration Rovers?"
"How many have heard of the Cassini mission?" "How many know where it is?"
"How many have heard of the Dawn mission?" "How many know where it is?"

(As a control, see how many people know what planet the Mars Exploration Rovers are on).

Well, one anecdotal piece of evidence is the activity level of the MESSENGER forum here. That project is also using a one image a day policy. The current thread for the project, has only 25 messages in the 4.5 months since the mission began.

That's not entirely a fair comparison -- orbital survey missions are just inherently not as sexy as the treks of the rovers or the Voyager-over-and-over-again tour of Cassini; so if I'd had to prioritize which two missions I'd want all the raws from, I'd've picked those two. Interestingly, most orbital survey missions appear to be following the image-a-day-ish model. MESSENGER - Odyssey - MOC did the same thing, in their day - Cassini's tried to have it both ways, raws plus captioned image a day (and how many of us actually pay any attention to those captioned images?) - HiRISE effectively does one-ish captioned per day, though their 3-month PDS release timeline appears to be close enough to immediate for just about everybody. LROC does 3 per week.

Ironically, it's now that Dawn's in survey orbit that I care less about getting all the images. I wanted them all when the images would have let me ride along with the adventure of navigating to a new, unexplored world. We've arrived, and we've just been given a trove of riches, a survey of all longitudes. And now we'll be fed postage stamps that we won't get to choose. I expect our communal attention to wane.

In my opinion, there have only been one microscoop and one miniscoop.
The microscoop was the discussion we had here when the first Enceladus images were sent back with the geysers. Once they were confirmed there was some high-fives around here, but nothing "public" was ever really said.
The miniscoop was when a certain reporter asked a certain scientist about certain features returning to a certain planet during a lecture before the scientist got to see the images. Said scientist has made their feelings very well known about the incident, but beyond the immediate event the only public fallout that I know of was on here. The scientist's attitude in this specific case was very much of a gatekeeper to knowledge, vs the Steve Squyres' mentality of a co-explorer and companion on a wonderful journey. I don't go to the scientist's mission website precisely because of that attitude, and I'm probably not the only one. I'd much rather hang out with friends who are happy to point me in the right direction to do it myself or do it for me.

There are some real benefits to engaging with your fan base. Dawn could be getting continuous rotation movies like above, or 3d stereo images (red/blue, cross-eyed, parallel), Kodak moments, armchair analysis, comparison views, preliminary maps, etc, etc, done for free by a bunch of people who love space exploration, and love talking about it to their friends and families and schools (and congresspeople). We could be having discussions about the best image of the latest batch, discussing what causes A and B and C, and WTF is D?? Instead we'll get one image a day, sure it's showcasing something interesting, but I'm sure each of us have a different view of what is interesting, and even if we don't all necessarily talk, would like to hear the discussion among the rest of the UMSF crew.

That being said, I do want to thank the Imaging Team for their presence here at UMSF. Even though you'll probably get no credit for it, this is definitely outreach and it matters to me.

They're not falling short of what's ordinary, though. That was the point. When you ask them to do something that is extraordinary, you could at least do them the courtesy of admitting that it is. If the daily image release thing wasn't ordinary for HiRISE, for LROC, for MESSENGER, well then maybe I could understand the flogging here. It was, IMO, beginning to lack context. That's it. Not saying my heart's not in the same place.

Dear Dawn, thanks for the daily images. Some missions do more. Please follow their lead. The question of whether there can be too much released to the public was settled by pathfinder. There cannot be too much. It's be resettled by every mission that's turn on the firehose since.

I've read with interest the follow-on traffic, but it seems to me that the answer is no - the simple and direct question as to why this policy has been adopted for dawn image release, has not been asked/answered. We can all reasonably speculate that it has to do with budget or PI's wanting to publish or who knows what else - just curious as to whether anyone in the Project has stepped forward to explain the rationale for this decision.

Well, to change the tone of the conversation, I'm going to state what I'm looking forward to seeing,
namely - CAVES - or at least the observed openings. The presence or absence will tell us a lot about
Vesta's evolution and as early Mankind found out, caves are really useful things.

A stereogram from still frames 50&51 of the movie (thanks to Emily for this!):
Click to view attachment(crossed eyes) Click to view attachment (parallel)
A detail of sharpened snowman crates:
Click to view attachment Click to view attachment

Talking about features, I think I would not step too much out of the line if I invite you to speculate about the feature in the red circle.

Sorry if the upload is in full size, someone please PM me to explain how to do the thumbnailing.

I think all the dark spots are caused by impact excavation of a buried dark layer. Most large craters reach under the dark layer and also excavate deeper bright material. This particular spot looks to me like a smaller crater that is almost completely within the dark layer, not reaching under it. If you enlarge it and brighten it it looks like a typical small crater with a lot of dark material on its inner rim and slumping down its walls.

Phil

The grooves/ridges are particularly interesting. Only one explanation makes sense to me, particularly after watching the rotation movie, and that is ring decay. Probably multiple impact-generated rings, at multiple orientations, over the course of Vesta's history. This is much as anticipated in the Small Body Grooves thread. We'll see more on Ceres

My thought process is similar to Phil's. There exists darker material beneath the surface. The black streaks on the crater walls are caused by slumping and mass-wasting, possibly triggered or accelerated by regional impact shocks. The speckled area looks like it could have been caused by a spray of ejecta impacts. The other possibility is that a loose cluster of small debris impacted the region, perhaps a small Itokowa-like body was pulled apart in an encounter that set it on a trajectory toward Vesta.

I call geysers!

Ring decay seems unlikely to explain most of the grooves, since many of them (especially the far-northern big ones) are not "great circles" and thus curve along the surface, and could not have underlain a ring system, even if the rotation axis had shifted. Better mapping of the Vesta surface and the gravity figure as the mission progresses will shed light on this. If the gravity field is "weird" enough, it would discourage ring formation.
When I look at the distribution of crater ejecta back onto a rapidly-rotating Vesta from the south pole impact (who did that simulation?), plus massive seismic forcing, and then extension cracking with debris collapse, I see a possible explanation. But extension cracking is a bit dirty, and doesn't usually result in such straight lines. So I am not satisfied yet with this picture.

http://www.planetary.org/blog/article/00002906

Jutzi/Asphaug... who incidentally just tried to explain the moon's farside/nearside dichotomy with impact sims.

Could the layer of dark stuff (assuming that's what it is) be remnants of (the hypothesized) basalt flows that have been protected with a mantle of ejecta from the South Pole crater (SPC)? If so, subsequent impacts would serve to expose the basalt under the ejecta, as appears to be the case.

Speaking of SPC itself, what was used to determine an age of 1 billion years? Was it the lack of craters in its interior? In that case, 1 BY would be the age of a resurfacing of the interior, not necessarily of the impact itself. Considering that the the interior is a churned mess, any previous, readily observable cratering record would have been at least partially disrupted by the slumping and flow of material.

That estimate didn't come from Dawn data, so definitely not crater counts. AFAIK it comes from characteristics of the family of asteroids believed to have been produced by the impact.

Yeah. Now that I think of it, I barely remember reading something about that. I even have bits of one of those asteroids sitting on my desk.

With all this incredible photography, Vesta is going to be an excellent specimen for a foldable map.
Tayfun -- are you out there with your CADCAM machine still operable? How long until we have enough data (a "shape model" do they call it?) for you to carve one for me of this beast, er, lady?
Chuck

I agree, not all of the grooves are obviously due to ring decay. The most obvious candidates are the circum-equatorial grooves, though they seem to overlay grooves in different planes as well. The great-circle nature of the grooves will be easier to ascertain once a good 3D model of the surface is in hand. I suspect that a sufficiently "weird" gravity field may not necessarily prevent rings from forming, but would likely accelerate their decay.

I've been puzzled by the curving, non-great-circle grooves, and have had a difficult time explaining them. It occurs to me that if they are near the pole, and the ring decay is episodic, then they might be explainable in terms of a combination of the decay with rotation of Vesta. I can also envision a ring warped by interaction with a "weird" gravity field or satellite prior to impact as yielding these odd grooves. I really wish I had the resources to model this sort of thing :/

A model seems a few years away, why don't you try to transfer your methods into software environment.

No way I can see to extract the constant scale, not to say that I haven't been trying to transfer my Renaissance-era methods into the software environment.
Although to be fair, I'm not very skillful with PDS shape models, and perhaps someone else could do it.

I guess we may have to wait a few years, although the Itokawa team sent me a model a while back. You don't suppose the Dawn team has any plans to manufacture a small run of Vesta models?
Chuck

A new image has been posted here. Are we supposed to expect regular image releases from now on?

Probably best not to hold your breath for that.

Nice. This one appears to lack the resize and unsharp/high pass filtering of some of the recent press release images.

Nice you noticed! The image was created from the calibrated data product, and I try to alter it as little as possible. After all, y'all need something to do in your spare time.

Here is a first try from the rotation movie.

Anyone care to speculate on that long curved dark scar crossing a bunch of the left had side of the image? Re: regular images, Vesta is in survey orbit so it's probably taking way more pictures since the camera doesn't need to be turned away to thrust. Who knows if they will release more images just because they are capturing them.

-kap

Wow, that's very nice first try