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Unmanned Spaceflight.com _ Dawn _ Dawn's last mission extensions at Ceres

Posted by: Holder of the Two Leashes Feb 1 2017, 02:37 PM

This thread will cover all final phases of the Dawn mission, the end of which is not certain at this point.

XMO3 was suppose to be the final orbit, but now plans have changed and it will move into a new higher altitude and higher phase orbit soon. This will be XMO4.

An interesting monthly journal for January details the plan:

http://dawn.jpl.nasa.gov/mission/journal_01_31_17.html

Posted by: TheAnt Feb 4 2017, 06:09 PM

Ahuna mons have turned out to be what is called one "ice volcano"
(Used in lack of a better word in american English I guess, my native language got a word for underground water that instantly freeze as it enter the surface in the wnter which would have been very suitable here.)
Now why only a single such feature?
The http://news.agu.org/press-release/new-research-shows-ceres-may-have-vanishing-ice-volcanoes/ put some thought on that matter and suspect there's other ones that have flattened out and started a search for potential other sites.

Posted by: ngunn Feb 4 2017, 07:10 PM

QUOTE (TheAnt @ Feb 4 2017, 06:09 PM) *
Now why only a single such feature?


Another possible answer might be that the whole of Ceres is acting like a single pressure vessel with relatively fluid contents. This would require only a single relief valve (at any given time).

Posted by: Gladstoner Feb 4 2017, 08:16 PM

QUOTE (TheAnt @ Feb 4 2017, 12:09 PM) *
Now why only a single such feature?
The http://news.agu.org/press-release/new-research-shows-ceres-may-have-vanishing-ice-volcanoes/ put some thought on that matter and suspect there's other ones that have flattened out and started a search for potential other sites.


Perhaps the raised area adjacent to Ahuna is such a feature:



The elevation of this area seems to be anomalous compared to the surrounding topography. It does not appear to be associated with any crater/ basin rims or central peaks. Its association with Ahuna seems to imply a relationship of some kind. The surface of this feature is heavily cratered, which means it has been around much longer than Ahuna. Either this feature is an area of general uplift associated with the formation of Ahuna, or it is an older volcanic edifice of the upwelling that produced Ahuna (i.e. 'ancestral Ahuna') that has subsequently suffered subsidence and erosion. Or perhaps both processes were in play. Finally, it is possible it presence there could be purely coincidental.

Posted by: TheAnt Feb 6 2017, 12:39 AM

@Gladstoner: You might indeed have pointed out Ahuna mons predecessor there.
But yes, it cannot be ruled out that it's associated with the current formation. We just have to wait for the verdict by the professionals.
Regardless of which two it turn out to be, I don't think it's coincidental.

What is interesting is the comparatively short timeframe for a feature like this to relax and get near invisible.
If it is lets say 10 MY, that would mean that there's some ongoing activity inside Ceres to create a feature like Ahuna mons.
The big question then will be if it's continuous or periodical.

Well this higher altitude orbit might perhaps get us a chance to catch an image of the possible fog over Occator. Backlit by the Sun would be the best way to catch it just as on Enceladus.

Posted by: Gladstoner Feb 6 2017, 06:12 AM

QUOTE (TheAnt @ Feb 5 2017, 06:39 PM) *
What is interesting is the comparatively short timeframe for a feature like this to relax and get near invisible.
If it is lets say 10 MY, that would mean that there's some ongoing activity inside Ceres to create a feature like Ahuna mons.
The big question then will be if it's continuous or periodical.


Based on the features' appearances and on the (apparent) lack of extensive activity on Ceres, I'd think any volcanic processes would be episodic.

Posted by: Daniele_bianchino_Italy Feb 8 2017, 09:46 AM

" Asteroid Dust Cloaks True Composition Of Dwarf Planet Ceres "

" Observations of Ceres indicate that asteroids might be camouflaged "
http://www.seti.org/seti-institute/press-release/observations-ceres-indicate-asteroids-might-be-camouflaged

" Dwarf planet Ceres camouflage by asteroid dust ":
http://www.space.com/35451-dwarf-planet-ceres-camouflage-asteroid-dust.html

Posted by: Daniele_bianchino_Italy Feb 8 2017, 09:53 AM

?
Is expected to map temperatures of Ceres? I expected Already for long time :-/

Posted by: Paolo Feb 17 2017, 06:03 AM

on today's Science (and behind the paywall... mad.gif )

http://science.sciencemag.org/content/355/6326/719

QUOTE
Organic compounds occur in some chondritic meteorites, and their signatures on solar system bodies have been sought for decades. Spectral signatures of organics have not been unambiguously identified on the surfaces of asteroids, whereas they have been detected on cometary nuclei. Data returned by the Visible and InfraRed Mapping Spectrometer on board the Dawn spacecraft show a clear detection of an organic absorption feature at 3.4 micrometers on dwarf planet Ceres. This signature is characteristic of aliphatic organic matter and is mainly localized on a broad region of ~1000 square kilometers close to the ~50-kilometer Ernutet crater. The combined presence on Ceres of ammonia-bearing hydrated minerals, water ice, carbonates, salts, and organic material indicates a very complex chemical environment, suggesting favorable environments to prebiotic chemistry.


see also the Science perspective article: http://science.sciencemag.org/content/355/6326/692
and the JPL press release: http://www.jpl.nasa.gov/news/news.php?feature=6751

Posted by: TheAnt Feb 18 2017, 04:46 PM

This is the kind of news that could have me literally jumping up and down.
Water, ammonia, salts, cabonates and now this!
It might be quite premature to speculate if any space agency will jump at this opportunity.
But it's a fact that Ceres would provide an easy target for a lander mission.
With the very low gravity it would even be possible to have a 'jumping' lander visiting several sites for sampling.
Even the idea of returning samples might be considered.
Aliphatic organic matter - it's not any of the lighter ones, they would be long gone, from a single spectral line it's hard to say how complex those molecules are.
But I'd give an arm and a leg to have closer look at a sample here on Earth.


Posted by: Explorer1 Feb 19 2017, 05:30 AM

There's probably already samples of Ceres on Earth, just not yet identified as such. All those craters must have made sprayed ejecta everywhere and some meteorites must be here now, just by probability.
Otherwise a sample return mission might in fact be easier than Mars; lack of atmosphere and low gravity making up for the greater difference in orbits...

Posted by: fredk Feb 19 2017, 03:50 PM

QUOTE (Explorer1 @ Feb 19 2017, 06:30 AM) *
lack of atmosphere

Doesn't atmosphere help you at Mars? You'd need a heck of a lot of fuel to brake from orbit and land without atmospheric drag. The drag would affect a launch from the surface, but with low launch speeds and thin atmosphere I'm guessing that's not a big effect.

Of course lower gravity at Ceres means lack of atmosphere won't be as important as it would've been at Mars.

Posted by: Explorer1 Feb 19 2017, 06:48 PM

Yes, I was talking about launching from the surface. I vaguely recall reading an article a few years ago about someone working on an engine for an ascent stage to get straight to Earth, no need for rendezvous; can't find it now. Anyway, this is a discussion for another thread, another time.

Posted by: Daniele_bianchino_Italy Feb 22 2017, 10:15 AM

QUOTE (Daniele_bianchino_Italy @ Feb 8 2017, 09:53 AM) *
?
Is expected to map temperatures of Ceres? I expected Already for long time :-/


Repropose my UP question... ?

I know that Ceres has no seasons like earth. However, we can say that it is entering its warm period. Dawn was arrived to Ceres in the beginning of the cold season. Too bad the mission will end before the maximun warm season of Ceres.


Posted by: PhilipTerryGraham Feb 25 2017, 11:02 AM

They're starting to publish XMO3 images on the NASA Photojournal! The first is http://photojournal.jpl.nasa.gov/catalog/PIA11240, taken on 11 February.

EDIT: https://commons.wikimedia.org/wiki/File:PIA11240_-_Occator_and_Ahuna.jpg, with annotations labelling all the discernible features in the image, per the https://planetarynames.wr.usgs.gov/images/ceres.pdf.

Posted by: Habukaz Feb 26 2017, 01:25 PM

QUOTE (Daniele_bianchino_Italy @ Feb 8 2017, 10:53 AM) *
?
Is expected to map temperatures of Ceres? I expected Already for long time :-/


Some pictures showing temperature have been generated. http://www.hou.usra.edu/meetings/lpsc2016/pdf/1883.pdf a few that I am not sure if have been posted to the Photojournal, where you can find the others. Don't know about global or other larger maps, or time series of temperature.

Posted by: Daniele_bianchino_Italy Mar 6 2017, 06:24 PM

QUOTE (Habukaz @ Feb 26 2017, 01:25 PM) *
Some pictures showing temperature have been generated. http://www.hou.usra.edu/meetings/lpsc2016/pdf/1883.pdf a few that I am not sure if have been posted to the Photojournal, where you can find the others. Don't know about global or other larger maps, or time series of temperature.


Thanks!
235 K -38C
196 K -76C
However, the VIR images are of the last year.
Ceres from this year begins to warm. The mission will not arrive to the maximum hot season of Ceres, but it could show more high temperatures in the next months....

Posted by: nprev Mar 10 2017, 04:14 PM

ADMIN MODE: Moved four recent posts to the former "Water Vapor on Ceres" thread, which has been retitled "http://www.unmannedspaceflight.com/index.php?showtopic=7789". I think that discussion will continue long after the Dawn mission is completed. Thanks! smile.gif

Posted by: Gladstoner Apr 9 2017, 08:08 PM

Long-range image taken on March 28:

https://photojournal.jpl.nasa.gov/catalog/PIA21401



The brightness of the Occator faculae is pretty subdued at this lighting and viewing angle.

Posted by: Holder of the Two Leashes Apr 27 2017, 01:16 PM

Dawn has lost another (third) reaction wheel. But it looks like the opposition studies scheduled for Saturday the 29th will not be affected.

https://dawn.jpl.nasa.gov/news/news-detail.html?id=6830

Posted by: Explorer1 May 2 2017, 04:15 AM

Opposition observation data received! https://dawn.jpl.nasa.gov/mission/status.html

Posted by: hendric May 3 2017, 04:20 PM

Man, if I ever win the lottery I'm going to work on making longer-lasting reaction wheels for space missions. sad.gif

Posted by: djellison May 4 2017, 04:37 AM

There are many old spacecraft with great reaction wheels still working fine. But there must have been some batch - some particular hardware version rev that has hit Kepler and Dawn.

Posted by: Explorer1 May 18 2017, 10:08 PM

Movie from opposition observations released: https://www.jpl.nasa.gov/news/news.php?feature=6845
New journal soon, presumably.

Posted by: Holder of the Two Leashes Jun 18 2017, 09:31 PM

Dawn's fate to be decided soon. Sending it off to a new asteroid is one option back on the table.

https://spaceflightnow.com/2017/06/17/dawn-mission-managers-await-nasa-decision-on-spacecrafts-future/

Posted by: hendric Jun 19 2017, 05:36 PM

QUOTE (djellison @ May 3 2017, 10:37 PM) *
There are many old spacecraft with great reaction wheels still working fine. But there must have been some batch - some particular hardware version rev that has hit Kepler and Dawn.


Yep, here's a comment from this article ( https://spaceflightnow.com/2017/06/17/dawn-mission-managers-await-nasa-decision-on-spacecrafts-future/ )

Benjamin Hunt
Mass and size are always an issue on spacecraft, especially deep space probes. Remember, however, that Dawn is an exception in terms of reliability...while reaction wheels have failed on other missions, they all (I believe) failed *after* completing their primary missions, and usually their extended missions.

That said, the reaction wheels that have failed on Dawn and several other spacecraft that have made the news have been noted as coming from a bad batch made by Ithaco Space Systems. The decreased lifespans weren't understood until it was far too late to do anything about it, except for the Kepler mission; those wheels were sent back to Ithaco for preventative maintenance shortly before launch, but even that didn't fix the problem. Still, Kepler made it 4 years before failure compared to its planned 3.5 year mission, and it is still returning very useful science, even if at a reduced capacity.

Posted by: jasedm Jun 19 2017, 08:29 PM

It would be fantastic news if the budget allowed for another asteroid flyby - I'd be pretty surprised though if the idea was approved.

Just a fun thought, would it be possible for Dawn to make it back to Earth? The idea of it matching orbits with the ISS and being examined up close after ten years of spaceflight is strangely thrilling (well to me at least smile.gif )

Posted by: nprev Jun 19 2017, 11:09 PM

It'd be possible to make it back to the Earth's vicinity, but probably only as a flyby. I don't see any practical way to get it into near-Earth orbit, even if the attitude control suite was fully operational.

No value added there. An asteroid flyby would be a much, much better option.

Posted by: algorimancer Jun 20 2017, 05:25 PM

What about a Europa flyby, with some asteroid flybys en-route? Not sure about the gravity gradient, but it might be more efficient to head inward and get an orbital assist from Mars, or it might not. Given the current state of knowledge about Europa, we could probably learn a lot from a targeted flyby -- and probably 10 or more years before we have an orbiter in place.

Posted by: djellison Jun 20 2017, 05:45 PM

Europa? No way it'll survive that far from the Sun and that sort of radiation dose. It really is Adiona, or Ceres. That's honestly all the options.

Posted by: tedstryk Jun 21 2017, 01:28 AM

Another asteroid flyby would be cool, but I'd like to stay at Ceres to monitor it though perihelion to see if any changes/outgassing can be detected.

Posted by: nprev Jun 21 2017, 04:22 AM

Perihelion is next April, and it does seem as if most http://www.nature.com/nature/journal/v505/n7484/fig_tab/nature12918_F3.html by remote sensors have happened around then.

I concur with Ted.

Posted by: hendric Jun 21 2017, 06:40 AM

I agree, stay at Ceres, but in a long term parking orbit that would allow for long term observations, with possible dips to a close orbit for flybys of anything interesting. I doubt we'll see significant changes, but maybe we'll get lucky. Occator crater is such an enigma, with the youth of the central mound. It is fascinating that two icy bodies (Ceres and Enceladus) that span an order of magnitude of sizes have localized activity.


Posted by: algorimancer Jun 22 2017, 01:35 PM

QUOTE (djellison @ Jun 20 2017, 12:45 PM) *
Europa? No way it'll survive that far from the Sun and that sort of radiation dose...

True, only 28% as much solar energy at Jupiter (if I did the math right). Not sure if this is more a problem for propulsion or simply keeping the electronics running. And I have no expertise in judging the radiation problem, though (having been a software developer once upon a time), I do wonder whether radiation tolerant software could be developed -- perhaps using the RAM in a multiply redundant fashion -- but that's a broader problem.

Anyway, my vote would be to go elsewhere if possible, with the argument being that flyby observations of another -- never explored -- asteroid would be more valuable than spending a bit more time at Ceres.

Posted by: bobik Jun 23 2017, 06:29 AM

QUOTE (nprev @ Jun 21 2017, 04:22 AM) *
Perihelion is next April, and it does seem as if most http://www.nature.com/nature/journal/v505/n7484/fig_tab/nature12918_F3.html by remote sensors have happened around then.

"https://www.nasa.gov/feature/jpl/ceres-temporary-atmosphere-linked-to-solar-activity ... Villarreal and colleagues showed that past detections of the transient atmosphere coincided with higher concentrations of energetic protons from the sun. Non-detections coincided with lower concentrations of these particles. What's more, the best detections of Ceres' atmosphere did not occur at its closest approach to the sun. This suggests that solar activity, rather than Ceres' proximity to the sun, is a more important factor in generating an exosphere."

Posted by: Daniele_bianchino_Italy Jun 24 2017, 01:36 PM

I would like to stay up Ceres to the perihelion. However, it depends on which asteroid destination Dawn team proposing.


Posted by: Holder of the Two Leashes Nov 1 2017, 10:54 PM

It is confirmed that Dawn will stay at Ceres. From now until the end of mission they will try to get into a closer orbit than ever before (at periapsis in a highly elliptical orbit), photograph the southern hemisphere with favorable lighting and observe Ceres at it closest point to the sun. The last part is in April with the greater possibility of Ceres outgassing an atmosphere.

https://dawn.jpl.nasa.gov/news/news-detail.html?id=6980

https://dawn.jpl.nasa.gov/mission/journal_10_31_17.html

Posted by: Explorer1 Jan 11 2018, 09:03 PM

Many details in the latest Dawn Journal: https://www.jpl.nasa.gov/blog/2017/12/dear-long-disdawnce-travelers

Descent to lower orbit should start in April, though targeting of specific areas for higher resolution imagery is not guaranteed.

Posted by: Daniele_bianchino_Italy May 9 2018, 08:10 PM

Where is Dawn? Notices on extended mission? unsure.gif

Posted by: Explorer1 May 9 2018, 10:46 PM

I'm assuming no news is good news, they are still spiraling down to the final orbit. Should be in an intermediate orbit May 14th, according to the last journal, and then May 31st to finish off.

Journal update: http://www.planetary.org/blogs/guest-blogs/marc-rayman/20180525-dawn-journal-getting-elliptical.html
Ceres reached perihelion, all is well with Dawn....

Posted by: Therion Jun 15 2018, 06:36 AM

Sharpened and enlarged views of Occator crater's eastern rim, boulders and landslides from altitude 44-48 km:



from https://photojournal.jpl.nasa.gov/catalog/PIA22524



from https://photojournal.jpl.nasa.gov/catalog/PIA22525



from https://photojournal.jpl.nasa.gov/catalog/PIA22526

Posted by: Explorer1 Jun 15 2018, 01:07 PM

Really neat limb view here: https://photojournal.jpl.nasa.gov/catalog/PIA22522
New journal entry posted; looks like EOM is estimated for September, October at the latest:
http://www.planetary.org/blogs/guest-blogs/marc-rayman/20180615-dawn-journal-spiralling-down.html
Running out of hydrazine for manouevres is not exactly a dramatic end, but what a journey it will have been!

Posted by: Daniele_bianchino_Italy Jun 18 2018, 08:45 AM

QUOTE (Therion @ Jun 15 2018, 07:36 AM) *
Sharpened and enlarged views of Occator crater's eastern rim, boulders and landslides from altitude 44-48 km:



from https://photojournal.jpl.nasa.gov/catalog/PIA22524



from https://photojournal.jpl.nasa.gov/catalog/PIA22525



from https://photojournal.jpl.nasa.gov/catalog/PIA22526


do you think of new, close-up images of Mount Ahuna??

Posted by: Daniele_bianchino_Italy Jun 18 2018, 08:47 AM

QUOTE (Therion @ Jun 15 2018, 07:36 AM) *
Sharpened and enlarged views of Occator crater's eastern rim, boulders and landslides from altitude 44-48 km:



from https://photojournal.jpl.nasa.gov/catalog/PIA22524



from https://photojournal.jpl.nasa.gov/catalog/PIA22525



from https://photojournal.jpl.nasa.gov/catalog/PIA22526


This is new images of Ceres?I do not find them update dawn nasa, or in another webasite, why?

Posted by: charborob Jun 18 2018, 10:58 AM

You can find those images https://dawn.jpl.nasa.gov/multimedia/images/.

Posted by: mcmcmc Jun 19 2018, 12:02 PM

QUOTE (Daniele_bianchino_Italy @ Jun 18 2018, 08:47 AM) *
This is new images of Ceres?I do not find them update dawn nasa, or in another webasite, why?

For unkown reasons they do not update twitter feed anymore since Dawn started descent to XAMO7 orbit on may 31th.

Posted by: Daniele_bianchino_Italy Jun 19 2018, 05:30 PM

QUOTE (charborob @ Jun 18 2018, 10:58 AM) *
You can find those images https://dawn.jpl.nasa.gov/multimedia/images/.



QUOTE (mcmcmc @ Jun 19 2018, 12:02 PM) *
For unkown reasons they do not update twitter feed anymore since Dawn started descent to XAMO7 orbit on may 31th.



Thanks :-)

I wanted to show My model of Ahuna Mons, with my hands (12x17 cm - 1cm about 1260 km) NO 3Dprinter (in the link there is also my occator crater):

I do not know if I can to insert here or remove moderator

http://antidotumtarantulae.altervista.org/Daniele_Bianchino_ArtGEO_asteroide_cratere_creta_model_ceres_cerere_occator_vinalia_cerealia_facula_planet.html


 

Posted by: Gladstoner Jul 2 2018, 03:39 PM

Cerealia Facula in Occator Crater:



https://photojournal.jpl.nasa.gov/catalog/PIA22477

I dare not speculate.

Posted by: Gladstoner Jul 2 2018, 03:42 PM

Vinalia Faculae, also in Occator:



https://photojournal.jpl.nasa.gov/catalog/PIA22478

Posted by: Gladstoner Jul 2 2018, 03:46 PM

Occator floor fractures:



https://photojournal.jpl.nasa.gov/catalog/PIA22551

Posted by: Explorer1 Jul 2 2018, 05:42 PM

Amazing! I do not see a single crater in the top mosaic. A surface as young and fresh as Sputnik Planum on Pluto?

Posted by: Therion Jul 2 2018, 06:20 PM

Amazing!
I really didn't expect we will see this thru Dawn's eyes.
Trully extraordinary engineering and mission planning accomplishment.

Reversed perspective of that mosaic makes more sense for my brain:



http://wonderousworlds.space/_/ceres-cerealia_facula_west_mound_and_vinalia_faculae_context.png

Posted by: Hungry4info Jul 2 2018, 07:40 PM

Approximate location of two of these images overlaid on the https://photojournal.jpl.nasa.gov/catalog/PIA20350 image.

 

Posted by: Floyd Jul 2 2018, 10:47 PM

Many thanks for the context Hungry4info

Posted by: GS_Brazil Jul 3 2018, 12:43 AM

QUOTE (Therion @ Jul 2 2018, 03:20 PM) *
Reversed perspective of that mosaic makes more sense for my brain:


Every brain works different ;-) My brain prefers to original, not the reversed.

Anyone knows if they were able to get more images of the area, or just the ones we saw today?

Posted by: Gladstoner Jul 3 2018, 02:42 AM

It kind of looks like tiramisu

Posted by: wildespace Jul 3 2018, 08:23 AM

My quck ICE version:



I tried using colour from an earlier https://photojournal.jpl.nasa.gov/catalog/PIA20355, but there is strong purple fringing there.

Of course, would be nice to see the central dome in such resolution.

Posted by: mcmcmc Jul 3 2018, 10:14 AM

is it a lake or a hill?!?
Are photo metadata available?

Posted by: wildespace Jul 3 2018, 10:44 AM

QUOTE (mcmcmc @ Jul 3 2018, 11:14 AM) *
is it a lake or a hill?!?
Are photo metadata available?

"The geometry of this feature is similar to a mesa or large butte with a flat top." http://photojournal.jpl.nasa.gov/catalog/PIA22477

A sodium carbonate-topped hill. Interesting that some of it streaked downslope.

P.S. Actually, looking at it in the surrounding context, it's more like a cliff or escarpment, because the south-western side of it seems to be level with the dark part of terrain, whereas north-east side drops off sharply towards the main mound.



Most of the flat white area here is slightly darkened, probably by space weathering and dust, but the bright edges with downslope streaks reveal fresher material. I wonder what it means in terms of dynamic processes on Ceres.


Posted by: Daniele_bianchino_Italy Jul 4 2018, 08:00 AM

It seems like exposure of sulfur after volcanic eruption, but this should be salt or sodium carbonate [wildespace].

Posted by: HSchirmer Jul 4 2018, 04:48 PM

QUOTE (Daniele_bianchino_Italy @ Jul 4 2018, 08:00 AM) *
It seems like exposure of sulfur after volcanic eruption, but this should be salt or sodium carbonate [wildespace].



Looks like the travertine springs in Pamukkale, Turkey.



Bigger
https://upload.wikimedia.org/wikipedia/commons/7/78/Pamukkale_panorama_2.jpg

Posted by: Gladstoner Jul 4 2018, 07:02 PM

My eyes are seeing something like this:





1. Bedrock (or 'bedrock')

2. Talus made up of fragmented bedrock

3. White material deposit

4. Scattered debris atop white material

5. Eroding white material

Posted by: Paolo Jul 4 2018, 07:08 PM

the Max Planck Institute site also has a striking image of the rim of Occator crater:
http://www.mps.mpg.de/Dawn-Unique-Views-of-Occator-Crater

Posted by: Jaro_in_Montreal Jul 16 2018, 10:11 PM

Finally a closeup: Cerealia Facula in Occator Crater, Ceres.



Posted by: Daniele_bianchino_Italy Jul 17 2018, 11:20 AM

I have Searched The areas seen so far at high resolution in Occator crater:

 

Posted by: Gladstoner Jul 18 2018, 03:57 PM

Mosaic of Cerealia Facula in Occator Crater:

https://photojournal.jpl.nasa.gov/catalog/PIA21924

Mosaic of the Vinalia Faculae in Occator Crater:

https://photojournal.jpl.nasa.gov/catalog/PIA21925


Posted by: Explorer1 Jul 18 2018, 07:54 PM

New Dawn journal, detailing how the images were obtained, and the last ion engine firing: http://www.planetary.org/blogs/guest-blogs/marc-rayman/dawn-journal-going-out-on-a-high.html

Posted by: Therion Jul 18 2018, 08:07 PM

Oh my! Those mosaics are absolutely stunning!

I see lot of pockmarks (pits/craters) on that white surface, although gray material within linear troughs/chasms and around that flat elevated mesa at SW is rather smooth.

Those bright fluvial features streaming down from flat-top mesa seems to be mixing with darker stuff which then covers underlaying bright deposits. I wonder, how amazing look would it be, standing down there next to central dome and looking SW at those streams!

Streams and landslides within troughs seems to be the youngest geological features here. Or those pockmarks all around the bright stuff are not impacts, but rather some sublimation-pits or even cryovolcanic calderas??

Either way, it's crazy landscape..

Posted by: mcmcmc Jul 19 2018, 07:10 AM

Each pixel should cover around 3-3.5 meters in these images.

Posted by: Daniele_bianchino_Italy Jul 19 2018, 08:42 AM

QUOTE (Therion @ Jun 15 2018, 07:36 AM) *
Sharpened and enlarged views of Occator crater's eastern rim, boulders and landslides from altitude 44-48 km:



from https://photojournal.jpl.nasa.gov/catalog/PIA22524



from https://photojournal.jpl.nasa.gov/catalog/PIA22525



from https://photojournal.jpl.nasa.gov/catalog/PIA22526


QUOTE (Jaro_in_Montreal @ Jul 16 2018, 11:11 PM) *
Finally a closeup: Cerealia Facula in Occator Crater, Ceres.





Your images are enlarged more than those inserted on: https://dawn.jpl.nasa.gov/multimedia/images/ceres.html
WHy? I would like to see these bigger,

Like these: https://www.jpl.nasa.gov/images/dawn/20180716/PIA21924.jpg

we would not have great images of Hauna mons if I understood correctly but only of crater 0ccator . .

Why did not we have temperature maps for Ceres?
..
.

Posted by: Gladstoner Jul 19 2018, 06:13 PM

It is proving quite difficult to visualize topography in the Cerealia Facula mosaic. For instance, the fractures keep appearing as ridges to my eyes.

Is it yet possible to produce 3D images, or lay portions or all of the mosaic on an elevation model?

Posted by: Floyd Jul 19 2018, 06:41 PM

Save the image on you computer, open in an editor and rotate 180 degrees. Light is coming from wrong angle for your brain to work--mine too--till flipped

Posted by: Gladstoner Jul 19 2018, 09:20 PM

QUOTE (Floyd @ Jul 19 2018, 12:41 PM) *
Save the image on you computer, open in an editor and rotate 180 degrees. Light is coming from wrong angle for your brain to work--mine too--till flipped


I already did that, and now it looks like the light is coming from below. smile.gif

The extreme light-dark pattern really fools the eyes.

Posted by: wildespace Jul 21 2018, 09:29 AM

QUOTE (Gladstoner @ Jul 19 2018, 07:13 PM) *
Is it yet possible to produce 3D images, or lay portions or all of the mosaic on an elevation model?

Someone made this 3D model: https://sketchfab.com/models/6a163a690a9b44448537eb745e24f5fa
Would be very nice to see the new imagery over this model!

Posted by: Adam Hurcewicz Jul 22 2018, 08:57 AM

Here is my 3D version of Ahuna Mons.
I use JMars software to generate DTM and ortho texture (LAMO phase) and create CMOD model to Celestia.

https://www.youtube.com/watch?v=EMW4bXI9-o8


Posted by: Gladstoner Aug 2 2018, 09:11 PM

Parallel structures:

https://photojournal.jpl.nasa.gov/catalog/PIA22643

Posted by: Adam Hurcewicz Aug 3 2018, 04:36 PM

From this 2 images central peak of Urvara crater I made a composition smile.gif
https://photojournal.jpl.nasa.gov/catalog/PIA22627
https://photojournal.jpl.nasa.gov/catalog/PIA22636




and comparison with old images FC21B0055129_16035075527F1C versus https://photojournal.jpl.nasa.gov/catalog/PIA22627


Posted by: Explorer1 Sep 4 2018, 07:18 PM

New Dawn journal (looks to be the penultimate one, sadly), going into detail on EOM http://www.planetary.org/blogs/guest-blogs/marc-rayman/dawn-journal-denouement.html

Some new images here: https://dawn.jpl.nasa.gov/multimedia/images/#gallery-1

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