Ceres Low-Altitude Mapping Orbit (LAMO) |
Ceres Low-Altitude Mapping Orbit (LAMO) |
Dec 22 2015, 04:50 PM
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#1
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
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Dec 22 2015, 09:03 PM
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#2
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Member Group: Members Posts: 154 Joined: 21-April 05 From: Rochester, New York, USA Member No.: 336 |
LAMOs are going to be good.
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Dec 22 2015, 09:11 PM
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
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Dec 23 2015, 01:07 AM
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#4
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
Something went very wrong there-- my first impression was "need to deinterlace" but it's too blocky for that.
I'm having a time figuring out what is where on these wrt the HAMOs. The shots are oblique and I'm not accustomed to the scale. I'll be better once I find the epiphany of a landmark or two. The Azacca Crater (??) / Samhain Catena area of the LAMO images pia20184 pia20185 and pia20186 may be covered by HAMO images HO-9, 27, 42, 45 and Survey Orbit images SO-11, 48. --Bill -------------------- |
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Dec 23 2015, 01:17 AM
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#5
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Dec 24 2015, 11:13 PM
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#6
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Merciless Robot Group: Admin Posts: 8784 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Looks like we're there now! Press release. Probably gonna be a bit slow for a couple of days due to US holidays, but please post all relevant discussion here; thanks!
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Jan 12 2016, 02:04 PM
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#7
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Member Group: Members Posts: 154 Joined: 21-April 05 From: Rochester, New York, USA Member No.: 336 |
... very slow :-)
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Jan 12 2016, 03:24 PM
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#8
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
Funny that you chose today to post to this thread.
https://www.nasa.gov/feature/jpl/new-detail...in-dawn-images/ Four, including the one posted have been added to the photojournal: http://photojournal.jpl.nasa.gov/catalog/PIA20191 http://photojournal.jpl.nasa.gov/catalog/PIA20192 http://photojournal.jpl.nasa.gov/catalog/PIA20193 http://photojournal.jpl.nasa.gov/catalog/PIA20194 -------------------- |
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Jan 12 2016, 04:19 PM
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#9
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Senior Member Group: Members Posts: 1074 Joined: 21-September 07 From: Québec, Canada Member No.: 3908 |
Spectacular! Unfortunately, the TIFF files on the Photojournal are identical to the JPEG files, that is, they are affected by JPEG artifacts. I wonder why they bother to post the TIFF images. There should be much more detail in the uncompressed images, whenever they become available.
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Jan 12 2016, 05:00 PM
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#10
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Newbie Group: Members Posts: 12 Joined: 26-August 15 Member No.: 7733 |
Looking at the white spot, I see it's made of several smaller white spots, just like in the Occator crater.
http://photojournal.jpl.nasa.gov/jpegMod/PIA20193_modest.jpg |
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Jan 12 2016, 10:08 PM
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#11
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Member Group: Members Posts: 154 Joined: 21-April 05 From: Rochester, New York, USA Member No.: 336 |
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Jan 13 2016, 04:25 AM
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#12
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Member Group: Members Posts: 316 Joined: 1-October 06 Member No.: 1206 |
Look at the floor of Dantu!
http://photojournal.jpl.nasa.gov/jpegMod/PIA20193_modest.jpg wowowowow. Impact melt craziness? And the obligatory white patch. P Edit: actually reminds me a bit of the 'spider' at the center of Caloris on mercury. Different materials of course but... |
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Jan 13 2016, 08:27 AM
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#13
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
Since they haven't started designating LAMO images with numbers, I'm lettering them until they do.
LAMO F LAMO G LAMO H LAMO I -------------------- |
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Jan 13 2016, 06:19 PM
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#14
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 15 2016, 07:24 AM
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#15
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 15 2016, 07:37 PM
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#16
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 17 2016, 06:06 AM
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#17
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Jan 20 2016, 04:00 AM
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#18
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
some more renderings
This time "Kupalo Crater" http://dawn.jpl.nasa.gov/multimedia/images...tml?id=PIA20192 |
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Jan 20 2016, 04:42 AM
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#19
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 21 2016, 04:22 PM
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#20
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 24 2016, 12:14 AM
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#21
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 25 2016, 08:17 PM
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#22
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 26 2016, 08:17 PM
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#23
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 26 2016, 08:46 PM
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#24
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
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Jan 26 2016, 09:52 PM
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#25
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
My best guess is that right after impact, the basin uplifted into something resembling the central ridge you see, and as it rapidly cooled, the exterior sort-of buckled inwards as it compressed from cooling unevenly. This would only be possible if this region is heavier in rocky material.
I will say, I am especially intrigued by the feature at center left, along the central ridge. Tall peak, central pit, who knows... -------------------- |
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Jan 26 2016, 11:21 PM
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#26
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Junior Member Group: Members Posts: 48 Joined: 20-December 14 Member No.: 7370 |
Fascinating features. So what's with those radiating 'bird feet'? If I saw those hills on Earth, I'd think they were an erosional remnant of a larger mountain. But on Ceres, there is no apparent process to remove the material in such a manner. I favor the least interesting explanation as evident in LAMO G, I think it's due to settling and sliding of the puffy ejecta in-fill of the craters. Most craters* start out as an empty cones, and in-fill by their ejecta and landslides, and the ejecta of countless other craters. The craters are filled of unstable relatively puffy fine-grained ejecta. Subsequent impacts cause huge Ceres-quakes which will cause landslides (clearly evident all over the place) and settling, which I believe is the majority of the cracks on crater floors. *Most craters (other then young ones big enough to have lava in-fill at the time of creation, and very large ones (I don't know what that size is on Ceres, and it's probably a function of age)) e.g. old (earliest) craters have a harder surface which may rebound more. Also assuming it was mostly a molten interior at the time of formation, then the lava in-fill (and after a given crater could no longer expose lava) then elastic rebound would be decreasing as a function of age. The later craters would be formed in a puffy impact gardened surface which looks to be km thick. An impact in a loosely bound matrix would evacuate a clean cone and then have severe landslides back into the pit. It's even possible that most of the central peaks are in fact landslide conjunctions (i.e. if there are landslides all around the craters they would meet in the middle and after a few met the forming ridge/peak would accumulate subsequence landslide terminating debris as the crater in-filled. I think these type of processes may explain the majority of Cere's crater's features. I wonder what magnitude Cere's quake is generated for a given impact diameter and distance from the impact? |
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Jan 27 2016, 12:37 AM
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#27
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Jan 27 2016, 02:19 AM
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#28
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
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Jan 27 2016, 03:21 AM
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#29
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
The Asterisk Central peaks are likely volcanic.
--Bill -------------------- |
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Jan 27 2016, 09:29 AM
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#30
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
I'd like them to be volcanic as well but there's little to show they are. No visible flows anywhere really. Not that they couldn't have long since been erased, but there's no evidence to push for it. Several mound-like features are present with what would seem to be central depressions.
Also, interesting comparison Gladstoner. I definitely think there is some resemblance here. However, I have to wonder that if they have been through similar processes, in regards to Dantu, why has a small patch of bright material near the cracks remained while everything else has disappeared, especially a bright central patch of it in the center of the central ridge. One possibility is that it has been recently active, long after most of the bight material was covered up or insolation caused the material to become less reflective. But if it was recently active, then how? Strange place. -------------------- |
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Jan 27 2016, 01:21 PM
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#31
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Member Group: Members Posts: 423 Joined: 13-November 14 From: Norway Member No.: 7310 |
QUOTE Re: spots: I'm taking pics of small parts of Ceres, covering it over time. Don't have good Occator pics yet; eventually I will. Stay tuned! https://twitter.com/NASA_Dawn/status/692099462332682241 Haven't seen or heard any word on the mountain, yet. -------------------- |
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Jan 27 2016, 03:26 PM
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#32
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
My idea is that the really good LAMO images are spectacular and good material for papers, so they've not released them in the dozen-or-so daily images. After the papers get out and the data hits the PDS we'll have some jaw-droppers. Time will tell.
--Bill -------------------- |
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Jan 27 2016, 05:12 PM
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#33
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 27 2016, 08:48 PM
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#34
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
I definitely think there is some resemblance here. However, I have to wonder that if they have been through similar processes, in regards to Dantu, why has a small patch of bright material near the cracks remained while everything else has disappeared, especially a bright central patch of it in the center of the central ridge. One possibility is that it has been recently active, long after most of the bight material was covered up or insolation caused the material to become less reflective. But if it was recently active, then how? Yes, we may be seeing two different stages of the life cycle of some 'volcanic' process. The sparse white spots in Dantu could be the (relatively recent) dying gasps of activity. For an earthly analogy, I'm thinking along the lines of the cinder cones atop the dormant Mauna Kea (Hawaii) vs. the more robust lava flows from the younger Mauna Loa. |
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Jan 28 2016, 01:15 AM
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#35
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Member Group: Members Posts: 120 Joined: 26-May 15 From: Rome - Italy Member No.: 7482 |
I think it is a central peak, some as seen on the Moon or Mercury. I study enough geology, and volcanoes. I honestly don't see a signs of volcanic activity. However, I don 't know what form would a volcano over a small body without gravity 'as Ceres.
These is the only structures that seem cones, but perhaps just a coincidence .. This is a volcanic chain of example, not very clear volcano, but an expert recognizes obvious signs of volcano, although it is a not classical volcano |
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Jan 28 2016, 01:35 AM
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#36
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Jan 28 2016, 02:15 AM
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#37
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
I think it is a central peak, some as seen on the Moon or Mercury. I study enough geology, and volcanoes. I honestly don't see a signs of volcanic activity. However, I don 't know what form would a volcano over a small body without gravity 'as Ceres. These is the only structures that seem cones, but perhaps just a coincidence .. Plus, impact craters are more likely to be preserved on the summit of a mountain than on its slopes. |
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Jan 28 2016, 09:24 PM
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#38
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 28 2016, 11:25 PM
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#39
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Member Group: Members Posts: 114 Joined: 6-November 05 From: So. Maryland, USA Member No.: 544 |
Finally, a look into Kerwan, the sand dollar.
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Jan 29 2016, 07:56 AM
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#40
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
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Jan 29 2016, 06:07 PM
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#41
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
I didn't get to watch all of the SBAG Dawn presentation this morning. Hopefully I will get an update today from the NASA public affairs office about the recording and I will post it if available. From what I did see, it was a pretty good update to the status of the mission with lots of good slides and information. The slides should be posted by the end of the day which will include a pretty good shot of Haulani in LAMO. Below is a screen grab.
Also posted today was a nice animation from DLR, of a simulated flyover of Ceres, similar to the previous animation but with much higher resolution. Link -------------------- |
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Jan 29 2016, 07:23 PM
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#42
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Jan 29 2016, 07:34 PM
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#43
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Junior Member Group: Members Posts: 48 Joined: 20-December 14 Member No.: 7370 |
Fascinating features. So what's with those radiating 'bird feet'? If I saw those hills on Earth, I'd think they were an erosional remnant of a larger mountain. But on Ceres, there is no apparent process to remove the material in such a manner. I favor the least interesting explanation as evident in Kupalo Crater from LAMO PIA20192, I think it's due to settling and sliding of the puffy ejecta in-fill of the craters. Most craters* start out as an empty cones, and in-fill by their ejecta and landslides, and the ejecta of countless other craters. The craters are filled of unstable relatively puffy fine-grained ejecta. Subsequent impacts cause huge Ceres-quakes which will cause landslides (clearly evident all over the place) and settling, which I believe is the majority of the cracks on crater floors. *Most craters (other then young ones big enough to have lava in-fill at the time of creation, and very large ones (I don't know what that size is on Ceres, and it's probably a function of age)) e.g. old (earliest) craters have a harder surface which may rebound more. Also assuming it was mostly a molten interior at the time of formation, then the lava in-fill (and after a given crater could no longer expose lava) then elastic rebound would be decreasing as a function of age. The later craters would be formed in a puffy impact gardened surface which looks to be km thick. An impact in a loosely bound matrix would evacuate a clean cone and then have severe landslides back into the pit. It's even possible that most of the central peaks are in fact landslide conjunctions (i.e. if there are landslides all around the craters they would meet in the middle and after a few met the forming ridge/peak would accumulate subsequence landslide terminating debris as the crater in-filled. I think these type of processes may explain the majority of Cere's crater's features. I wonder what magnitude Cere's quake is generated for a given impact diameter and distance from the impact? Just a visual update on my hypothesis: The younger Kupalo Crater clearly shows landslide formed cracks and this view [below] from today's movie shows how the Dantu settling/landslide fault line cracks are most likely the same mechanism. ZLD's screen grab today (previous post) of Haulani in LAMO shows similar landslide cracks. Also the Kupalo and Dantu landslides both appear to end at the central "peak" area with a linear terminus pile-up. Note that landslides in .028g should travel much further then in 1g on earth. |
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Feb 1 2016, 11:16 PM
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#44
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 2 2016, 02:55 AM
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#45
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Feb 2 2016, 07:21 PM
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#46
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 3 2016, 02:16 AM
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#47
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
lamo 18 - PIA20308
low angle illumination like this ( approx. 10Deg. ) is pushing things a bit this required a lot of manual editing to correct the dem used i had it inpaint the shadows and dodge and burn the heightmap the first of the two is just a rendered mesh the second has the texture draped over it |
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Feb 3 2016, 07:16 PM
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#48
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 4 2016, 07:03 PM
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#49
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 5 2016, 06:45 PM
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#50
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 8 2016, 05:29 PM
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#51
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Member Group: Members Posts: 423 Joined: 13-November 14 From: Norway Member No.: 7310 |
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Feb 8 2016, 08:02 PM
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#52
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 9 2016, 02:13 AM
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#53
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Feb 10 2016, 12:12 AM
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#54
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Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
John, its very impressive!
-------------------- CLA CLL
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Feb 10 2016, 05:51 AM
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#55
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 10 2016, 05:43 PM
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#56
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 11 2016, 05:58 PM
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#57
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 13 2016, 06:14 AM
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#58
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
LAMO 26 - PIA20380
http://dawn.jpl.nasa.gov/multimedia/images...tml?id=PIA20380 this one has A LOT of small craters |
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Feb 13 2016, 05:07 PM
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#59
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 16 2016, 07:09 PM
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#60
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 16 2016, 09:08 PM
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#61
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
and the renders in Blender that go along with LAMO 27
and a Google photo album of My LAMO renders https://goo.gl/photos/iAtFUPmE4QVxpcY29 |
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Feb 17 2016, 01:38 AM
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#62
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
I feel like I hadn't seen some of those John. Those are all great!
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Feb 17 2016, 06:47 PM
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#63
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 17 2016, 07:27 PM
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#64
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
QUOTE I feel like I hadn't seen some of those John. Those are all great! some might not have been posted here. some were in the old hamo folder and there a few that once i get a mesh and look at them in 3d , there is not much to look at you end up with the problem of the vacation slide show pictures |
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Feb 17 2016, 08:41 PM
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#65
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Junior Member Group: Members Posts: 48 Joined: 20-December 14 Member No.: 7370 |
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Feb 18 2016, 01:52 PM
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#66
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
Comparison of the recent LAMO LO-28 image with an earlier HAMO image of episodic mass-wasting features.
https://univ.smugmug.com/Dawn-Mission/Ceres...es4x%2BLO28.png Reference: https://univ.smugmug.com/Dawn-Mission/Ceres...ient--annot.png https://univ.smugmug.com/Dawn-Mission/Ceres...-enh--annot.png --Bill -------------------- |
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Feb 18 2016, 06:07 PM
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#67
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 19 2016, 05:51 PM
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#68
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 20 2016, 03:32 AM
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#69
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Feb 20 2016, 03:57 PM
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#70
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
Created a new Ceres Gallery today and moved images into it:
https://univ.smugmug.com/Dawn-Mission/Ceres-LAMO-Images/ --Bill -------------------- |
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Feb 22 2016, 07:36 PM
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#71
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 23 2016, 05:32 PM
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Member Group: Members Posts: 423 Joined: 13-November 14 From: Norway Member No.: 7310 |
The latest image is quite the oblique beauty. I hope we get lots more of these.
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Feb 23 2016, 06:05 PM
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#73
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 24 2016, 07:47 PM
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 25 2016, 03:35 AM
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 25 2016, 10:03 PM
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 27 2016, 09:49 AM
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#77
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
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Feb 27 2016, 08:32 PM
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Senior Member Group: Members Posts: 1887 Joined: 20-November 04 From: Iowa Member No.: 110 |
The bright streaks on the crater walls, landslides of bright material or salt deposits left behind by flows of liquid?
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Feb 27 2016, 08:41 PM
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#79
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Feb 27 2016, 09:57 PM
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#80
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Feb 27 2016, 10:41 PM
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#81
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
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Feb 28 2016, 03:20 PM
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#82
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Senior Member Group: Members Posts: 3419 Joined: 9-February 04 From: Minneapolis, MN, USA Member No.: 15 |
Considering the extensive emplacement of impact debris mantling units all over Ceres, I would guess the top 500 to 1,000 meters of the surface is a battered, crushed layer of poorly mixed, brecciated debris. There are quite likely a huge number of salt and salty ice deposits embedded within this debris layer.
When craters are made in this kind of surface, these pockets of high-albedo salt (or salty ice) become exposed; more are exposed as mass wasting deflates large crater walls. Thus, the occasional white spots and streaks seen in crater walls. Now, this is completely separate from directly-emplaced cryovolcanic deposits, like what we appear to see in Occator. Those (and there are quite a fewer number of them than the smaller white spots) seem to be examples of deeper material moving volcanically up to the surface from deeper layers of soft salty ice (or even liquid salty water). That's a different emplacement mechanism from most of the small bright spots we see on crater walls, I think. Think of it this way -- take a surface composed mostly of black sand, and randomly embed a bunch of white pebbles in it. Then hit it with an impact. Your resulting crater will show mostly black sand walls, but every once in a while a white pebble will poke out through the major black sand matrix of the unit. And as crater walls recede due to mass wasting, new white pebbles are exposed. Now, just replace the black sand with the general dark material of Ceres' surface and the white pebbles with concentrations of salt and/or salty ice, and you have a model for what may well be happening on Ceres. -------------------- “The trouble ain't that there is too many fools, but that the lightning ain't distributed right.” -Mark Twain
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Feb 28 2016, 09:17 PM
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#83
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Senior Member Group: Members Posts: 3516 Joined: 4-November 05 From: North Wales Member No.: 542 |
When craters are made in this kind of surface, these pockets of high-albedo salt (or salty ice) become exposed; more are exposed as mass wasting deflates large crater walls. Thus, the occasional white spots and streaks seen in crater walls. Now, this is completely separate from directly-emplaced cryovolcanic deposits, like what we appear to see in Occator. I think the first paragraph quoted describes very well the likely formation process for white spots. So why invoke a different process for Occator? Any 'activity' there could just be the mass wasting of freshly exposed ices you already mentioned. |
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Feb 29 2016, 12:33 AM
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#84
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
I can't recall what conference was going on last week but I definitely saw some graphics pop up on Twitter that showed that the Dawn team is pursuing cryovolcanic processes for Occator. There was a nice side cut-away image as well. I'll try to find it and post if do. The possibility has been floated in several other recent talks as well.
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Feb 29 2016, 04:02 PM
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#85
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Member Group: Members Posts: 214 Joined: 30-December 05 Member No.: 628 |
If there are deposits of white salty material embedded at random locations in the regolith, then they should be uncovered more frequently around the rims of the craters than in the centers, should they not? Cryovolcanic scenarios do seem to fit a bit better better with the "bullseye" pattern we see in places like Occator.
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Mar 1 2016, 03:38 PM
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#86
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Mar 1 2016, 04:34 PM
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#87
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
Recent LAMO imagery and a current LAMO Index map:
https://univ.smugmug.com/Dawn-Mission/Ceres-LAMO-Images/ --Bill -------------------- |
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Mar 1 2016, 05:50 PM
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#88
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Mar 2 2016, 07:23 PM
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#89
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Member Group: Members Posts: 890 Joined: 18-November 08 Member No.: 4489 |
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Mar 4 2016, 05:23 AM
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#90
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Mar 4 2016, 08:49 PM
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#91
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Senior Member Group: Members Posts: 1074 Joined: 21-September 07 From: Québec, Canada Member No.: 3908 |
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Mar 4 2016, 10:04 PM
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#92
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Mar 5 2016, 06:02 PM
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#93
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
That ejecta seems to be more fluid than usual (as far as we've seen so far). In places, it resembles outflow channels on Mars. Some context of Ikapati Crater.... HAMO image 64: http://photojournal.jpl.nasa.gov/catalog/PIA20127 Survey Orbit image 30: http://photojournal.jpl.nasa.gov/catalog/PIA19599 This ejecta seems to be mostly confined within the low point of a larger, older crater (outlined in yellow): |
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Mar 5 2016, 07:38 PM
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#94
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
Was certainly thinking that as well Gladstoner. There is several very peculiar spots that look like very quick or non-viscous material moved quickly to fill the lower crater and surrounding area.
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Mar 6 2016, 07:55 AM
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#95
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
A checklist of interesting features in Ikapati Crater (labeled in image):
1. White spots. Their extent is minor compared to other craters. 2. Extensional fractures. These are on the floor, rim and ejecta. 3. 'Shotgun blast' pits. These seem to be more than mere clustered impacts. 4. Degraded central peak. The flat top (or pit?) contrasting with the fluted sides is quite interesting. 5. Fluvial-like flow structures. |
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Mar 7 2016, 06:09 PM
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#96
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
Ahuna. The closer we look, the more mysterious it becomes. I'm still thinking "my gawd, it's full of stars... "
--Bill -------------------- |
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Mar 7 2016, 07:01 PM
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#97
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Senior Member Group: Members Posts: 2091 Joined: 13-February 10 From: Ontario Member No.: 5221 |
How large is the gap between the rim of the crater and Ahuna's slopes? The caption says 35 m/ pixel (here), so less than a kilometer separation, by my count. Is it just a coincidence that the mountain is so close?
What an odd view one would have standing on the surface there, too... |
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Mar 7 2016, 09:04 PM
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#98
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Member Group: Members Posts: 715 Joined: 3-January 08 Member No.: 3995 |
That terrain on top of Ahuna.... It just seems to have no rhyme or reason. If anything, it appears like a souffle that has risen and collapsed back down a bit (with some subsequent mass wasting around the edges).
Oh, and that hanging valley on the west side of the summit is spectacular. |
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Mar 7 2016, 10:56 PM
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#99
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Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
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Mar 8 2016, 12:17 AM
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#100
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Senior Member Group: Members Posts: 2998 Joined: 30-October 04 Member No.: 105 |
QUOTE (Gladstoner) That terrain on top of Ahuna.... It just seems to have no rhyme or reason. I can't quite place with anything known. And the walls, NW to SE, still look rather vitreous and translucent. And the talus (or lack of) at the toe of the slope. I predict views with different lighting angles and a series of oblique views. Here is a montage of Ahuna from SO6 through HO1: https://univ.smugmug.com/Dawn-Mission/Ceres...mtn_montage.png --Bill -------------------- |
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