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edit: For all the cliff-doubters in comments, here's a quote of Project Scientist Ken Farley in the new NASA video After the Landing: An Update about NASA’s Perseverance Mars Rover after 01:05:44 (timestamp may degrease after the 31 minutes of leading emptiness is edited out similarly to this)

...and also in the background we believe that we can see the delta; there are features in the back that look like the cliffs of the delta. So when we get those additional images back that Jennifer was mentioning we should know a lot more about that. And we can also see some sand dunes in there...

NASA's Perseverance Rover Landing Ellipse in Jezero Crater shows the 7.7 x 6.6 km ellipse.

The image shows what looks to me like cliffs, and I get that same impression from the screen shot of a NASA animation below as well.

Question: How tall are the steepest features (which look like cliffs to me) within the Perseverance rover's landing ellipse?

Perseverance Rover 7x7 x 6.6 km Landing Ellipse in Jezero Crater

Source and full image source and more

Screen shot from Fly Over Mars 2020 Landing Site Jezero Crater in NASA Animation

Screen shot from Fly Over Mars 2020 Landing Site Jezero Crater in NASA Animation

Cropped from PIA24483:

Cropped from PIA24483

uhoh
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    There's a pretty decent topographic map here. Perhaps not quite the resolution you're looking for, but it looks like it's maybe ~100m. – Phiteros Feb 14 '21 at 08:18
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    From "Sedimentology of the Jezero western fan deposit 1. evidence for a deltaic origin and implications for future exploration":: "Dips range from 0.5-9⁰ and ...." . ( the link didn't work). So these features are certainly no cliffs ! – Cornelis Feb 14 '21 at 16:44
  • Regarding your question, can't one consider the part of the delta shown in my answer, as one feature ? You can draw a straight line there on the image from green to white. – Cornelis Feb 15 '21 at 09:05
  • @Cornelisinspace could be, I've only defined them as "features (which look like cliffs to me)" to allow for some room for terminology for those steep elevation gradients the you wouldn't want to land on. – uhoh Feb 15 '21 at 09:52
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    The descent stage (flying crane) has good radar altimetry and some crossrange capability, so it should be able to avoid landing (or crashing into) any of the more severe terrain in the landing site. I',m hoping for some very spectacular landscapes even directly after landing and deploy. – CuteKItty_pleaseStopBArking Feb 15 '21 at 11:51
  • @PcMan I think you will be disappointed. Those "cliffs" have slopes of 30⁰ at most. – Cornelis Feb 18 '21 at 08:32
  • @Cornelisinspace check the edit – uhoh Feb 19 '21 at 02:43
  • Sorry, wrong image ! Doesn't this one look better ? https://i.stack.imgur.com/ia4U6.jpg – Cornelis Feb 24 '21 at 10:51
  • @Cornelisinspace I don't know but the image is stunningly beautiful, thanks! – uhoh Feb 24 '21 at 10:59
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    @Cornelisinspace No, those are not the cliffs that 'worried' me. THESE are: https://cdn.cnn.com/cnnnext/dam/assets/210305154421-03-mars-perseverance-rover-0305-exlarge-169.jpg It may just be me being silly, but that angle *REALLY* looks a bit steeper than "slopes of 30⁰ at most" – CuteKItty_pleaseStopBArking Mar 06 '21 at 06:45
  • @PcMan No doubt about that spectacular mesa or butte ! The answers are from before the landing and although that butte might be a remnant of the delta, the "cliffs of the delta" are still a few km away. – Cornelis Mar 06 '21 at 09:27
  • @Cornelisinspace Just needed to show you that your condescending putdown of "you will be disappointed. Those "cliffs" have slopes of 30⁰ at most" was totally wrong. – CuteKItty_pleaseStopBArking Mar 06 '21 at 21:46
  • @PcMan I should have said: 'If you expect the "cliffs of the delta" to be (nearly) vertical rock facies you might be disappointed ". – Cornelis Mar 07 '21 at 09:41
  • @Cornelisinspace true.. that cliff on the right of the image i attached is not vertical. IT HAS A 15 DEGREE OVERHANG! – CuteKItty_pleaseStopBArking Mar 07 '21 at 10:15
  • @PcMan Spectacular, but the "cliffs of the delta" are still a few km away ! – Cornelis Mar 07 '21 at 10:54

2 Answers2

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After carefully cross-referencing the landing ellipse picture with this topographic map provided by ESA, it looks like the cliffs in the center of the ellipse are about 50 meters tall, and no more than 100 meters.

Zoomed in image of topographic map.

Close up of terrain cross-section.

Phiteros
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5

Jezer delta
Credit: NASA/JPL/University of Arizona/USGS
Click on the image, and then again for a closer view.

The image above is a part from HiRISE,Digital Terrain Models and shows a colored elevation map of the eastern part of the delta deposit.
(Purple is -2679 m, brown is -2388 m, so a full-scale elevation difference of about 300 m.)
I would say the shaded, south part of the tongue in the middle of the image has one of the steepest slopes, and measured with Mars Trek the smallest horizontal length of the slope there is about 140 m.

Slope
Slope of the south part of the tongue, (remarkable detailed) screenshot made with Mars Trek.
The yellow horizontal measured line is 140 m. long.

colored bar

With the colored bar above it's rather hard to estimate the height but I would guess the slope goes from yellow-brown to reddish-brown.
Then the height could be about 70 m and the steepness of the slope at the south part of this feature would be 27$^{\circ}$.

Cornelis
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