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New Shapemodel!

Here is my latest shapemodel:

It is as good as I believe can be done with the current limited data-set. It is built by correlating 150 surface features over 120 navcam and OSIRIS frames. Each image has had its viewing geometry reconstructed using sparse bundle adjustment. Then a select number of images where used to derive dense depth from stereo data. To combat the noise in the stereo data IĀ used shape from shading to create high resolution local data.

For the parts of the comet currently in darkness I have used images of the limb against the slightly brighter dust cloud to constrain the volume that the surface is inside.

I have smoothed out the “unknown” areas to make the model a bit prettier.

There are areas especially around the neck with artifacts and seams. I have not fixed them because the model is continuously made obsolete by the steady stream of new images being released.

As soon as new data becomes available I try to update the model. And I will post a new one here if there are meaningful changes to the model.

The model is Copyright Mattias Malmer CC BY SA 3.0

I would like to be credited for the creation of the model and a link to this blog would be appreciated.

Image source credits:





The slopes and roughness of the Philae landingsite

I wanted to get a feel for the landscape in which Philae is set to land. I had already built a resonably accurate terrainmodel of the area. So I decided to play a little with the data.

The result are these two maps.

First a map showing the slope of the terrain. There are a few really steep places in the landing area but most of it is thankfully rather flat.

Then a slightly more worrying map showing the surface roughness. There are a few boulder fields that scare. but much of the area seem to be smooth (at least on the scales resolved in my dataset.)

Obviously my methods are not as refined as the ones employed by the mission teams but these maps should give an idea of the challenges facing the little lander.


I also made this Anaglyph:


Testing the Planetarium version

I’m preparing a version of my shapemodel for rendering in realtime.

Dipl. Ing. (FH) Rainer Christiansen, curator of the Mencke Planetarium in Gluecksburg, contacted me and suggested the possibility. Working under his supervision we converted the model to the E&S digistar format. This video was recorded by Rainer as part of the testing of the models performance in theirĀ Evans & Sutherland Digistar planetarium system.

Mencke Planetarium:

Shapemodel progress

Spaceflight Now feature a couple of images of the side of the comet that we have seen very little of.

One of the photos shows a monitor screen displaying this rare gem:

I combined the tv screen photo with an earlier cropped OSIRIS release

a bit of alignment and color balancing led to this “new” OSIRIS shot:

Armed with this new shot I had enough to coax out some stereo coverage of the region and add to the side of my Shapemodel.

I will put the new mesh online in a couple of days. It needs a little more work.