Looking at Erebus in a regional context, it should be remembered that Mars has been bombarded over the past few billion years and that Erebus is not a standalone feature. This MOC image shows Erebus in relation to other impacts in this area. It seems to me that the three large craters ("Purgatory", Erebus and Terra Nova) are contemporaneous since they appear equally eroded. I've also included an image layer showing overlying large sand drifts.

--Bill



edit: image updated

Here is a larger scale regional image showing eroded craters in the etched terrain between Erebus and Victoria.

--Bill



EDIT: revised image per posts #3 and #5.

I think it's difficult to identify some of those features you have marked as craters. And your rover path is a little way off to the left

There is a large area around Victoria crater that appears to be free of dunes - or much smoother than the surrounding plains. Good for driving on

Interesting, Bill.

"Find the circle" is a game which gives different results every time you play it. I think most of yours are OK, but I might add one or two, or remove a couple. But the basic idea is good, I think. There are craters here, very eroded but faintly visible. I would not have said the big craters were equally eroded, I think there's a clear progression of degree of erosion and filling, plus overlap - Purgatory (oldest), Terra Nova, Erebus (youngest).

And the rover path... your north arrow is off, and that's causing you to rotate the path. The image is within a degree or two of north-up anyway, and the long rover path should be near-vertical on the image. In fact you can see Viking and Voyager craters as small bright dots in the image north of Erebus, and the path should run between them.

This is all meant constructively. I really like the mapping work being done here, by everybody. I'm hoping Dilo will give us another reprojected map soon. And I would personally like to see some of this taken back to earlier in the mission.

Phil

>>I think there's a clear progression of degree of erosion and filling, plus overlap - Purgatory (oldest), Terra Nova, Erebus (youngest). <<
Think so too Phil. Fantastic that we are at a position with Oppy where we find all these different old craters for investigation.


Btw. Is Dilo on vacation or what's up with him?

Not again that someone suddenly disappears who can deliver such great generated views from that POV-Ray software again - like Erwann.

You're right, the north arrow/path is off, and those three craters, although eroded, are not equal; Phil has the right sequence.

What can I say? I was still giddy at the prospect of seeing something besides sandy ripples, and in a hurry to get something posted before going out to do honey-do's.

Happily, the drawings are made on separate layers and it'll be easy to fix.

Sunspot, that smoothish area is the ejecta blanket of Victoria; it might be smooth as a babie's hind end, or it might be a field of impassable boulders...


Good feedback...

--Bill

Yes, Bill's circles drawings around Erebus are the ones buried impact craters. I found your comments very interesting.

I hope that with the sonar equipment of MRO (SARAD) will be able to describe better the nature of the subsurface arround that zone or not?

Indeed, the Victoria's crater must be the youngest of that zone since it is deeper, vertical alike slopes and have some rims around the crater or not?

Rodolfo

To me it looks like an ejecta blanket. Whether it is good driving or not remains to be seen.

tty

As much as I hope for Oppy to reach Victoria, do some good science, observing a larger stratigraphic record AND get us some very 'perdy pichures' for a pan -when I look at Victoria I can't help thinking of Oppy getting stuck some distance off the rim in that dark sand all around it.

But I try to be optimistic You could say I'm preparing for the worst -not reaching that HUGE crater...

Nico

Go back and compare Erebus's ejecta zone with Endurance's. All we saw as the rovers rolled up to the crater was odd (secondary impact???) pitting and some fractures here and there on a rumpled, relatively drift-free sand-and-blueberry-sheet with some scattered sulfate-rock cobbles.

Sol638 PanCam mosaic...