Help - Search - Members - Calendar
Full Version: Zhurong maps
Unmanned Spaceflight.com > Mars & Missions > Tianwen 1- 2020 Orbiter/Lander
Phil Stooke
I'm starting a map thread. It's hard to know what we will get but I expect a route map will emerge bit by bit. Maps showing the landing location will be easier to make initially.

Phil
Phil Stooke
Starting off with an overview of the site, with landing ellipses based on the work done at Hong Kong Polytechnic University. The initial site is indicated. The landing ellipse is about 60 by 20 km and if you center one at the initial site it contains two craters with rough ejecta blankets (bright in this image, which is Mars Odyssey THEMIS infrared with inverted shading). Two nearby ellipses were chosen to avoid the craters, and the western one was then moved a bit to avoid more rough terrain at its southern end. The landing site is very close to the center of that ellipse and about 40 km from the initial site.

Phil

Click to view attachment
Greenish
Until higher-res imagery arrives, here's a crop at CTX full-res (5.67 m/px) with a circle roughly at the dot in Phil's ellipse map. (merge of 2 CTX tiffs - 1km squares for scale reference but not referring to any particular origin)

I think the distance from center to edge of the image, about 3.5km, is the horizon distance from about 1.7m height on Mars.

Click to view attachment
Phil Stooke
It's clear that following this mission will be tricky and maps will be tentative and only sporadically updated for a while.

But you have to start somewhere. This is a VERY tentative start. A HiRISE image will improve the basemap, and eventually a reprojected panorama can be laid over that.

What I show here is all I know at present. I will update it when we get news. Let me know if anything else appears! I am assuming landing day was sol 0 but that may not be correct.

Phil

Click to view attachment
Phil Stooke
OK, HiRISE image and a new location.

Phil

Click to view attachment
Phil Stooke
The text accompanying the 'group photo' of the rover and lander together says that the camera was deployed 10 m south of the lander. Then the rover moved back towards the lander for the photo. I have illustrated that here (using a guess as to the locations of the camera and the rover during photography). All very uncertain of course. I don't think the date of the group photo was mentioned - before or after the Tianwen-1 orbiter image, so I can't add a date.

All this is subject to ongoing revision.

Phil

Click to view attachment
kymani76
I'm a bit late to the game as I had other work, but it's finally time for me to catch up with all the events.

Click to view attachment
Revised landing ellipses map, with initial one in green and final one in yellow. Grid is at 10 km with smaller landing site quadrants at 1 km.
kymani76
Click to view attachment
All landed hardware map in HiRise color. Grid at 1km.
kymani76
Click to view attachment
Traverse map, based on tracks visible when enhancing HiRise image. Note the small area size of the map. I get 75m of distance from track in close aligment with reported 80m distance.
Grid at 10m.

Click to view attachment
Wider landing map in color, with engine exhaust obscuring the area of recent activity. Grid at 100m.
Phil Stooke
After the second HiRISE image appeared I have made some big changes to my map. I decided that the dark markings west of the bright streak are probably not tracks after all - especially if you overlay the two HiRISE images, which makes the tracks east of the streak easier to see and the others less distinct. I also changed my interpretation of the 'group photo' from the deployed camera. The foreground surface in that image is more red on the left side and middle, and darker and less red on the right. I was interpreting that as showing the surface from the west side of the streak but now I think it's from the east, and that seems to match the geometry of the lander better as well.

All that may still be wrong! A Chinese map would be very useful. Until we get one HiRISE may be our best guide.

Phil

Click to view attachment
Phil Stooke
Bit by bit a map takes shape. This uses the new panorama.

Phil

Click to view attachment
Phil Stooke
And an overview map - this will be the standard resolution for mapping.

Phil

Click to view attachment
Huguet
And Zhurong is almost at the parachute... Would be nice to get a new Hirise.

Huge image with a recent path nice guess from here:
https://twitter.com/TheElegant055/status/1413594702054674432
Link to 50MB full resolution version:
https://drive.google.com/drive/folders/19PT...TILuTgwRZE4Mk8E
Bill Harris
So, those light-toned features are barchan-like dunes. Wonder if we can determine the composition of these dunes? Or what the source of this material is?

--Bill
Phil Stooke
The LIBS instrument will give composition - they were within LIBS range.

There are dark dunes on Mars (e.g. Bagnold Dunes in Gale Crater) and bright features like this, usually called drifts or ripples. The dark features are made of basaltic sand and they can indeed by barchans - see also the Greeley Dune Field inside Endeavour crater. These brighter features are made of finer material, silt to dust sized particles. The reason the dark and light don't just mix to form mid-toned deposits is that the wind sorts particles by size. That finer material is probably mixed globally and doesn't tell much about local geology.

(Continue discussion in the other thread)

Here is a very rough update to the map using the new information. A new HiRISE image would be very useful! (or a Chinese map)

Phil

Click to view attachment
Huguet
China's Zhurong rover drives for over 410 meters on Mars
I believe, this means, we will get some parachute close-ups soon.

http://www.chinanews.com/gn/2021/07-11/9517522.shtml
"According to news from the National Space Administration, as of today (July 11) at 20 o'clock, the "Zhu Rong" rover has traveled a total of 410.025 meters and operating conditions are normal."
Phil Stooke
I updated my map with the parachute images. The sol dates might be one sol out depending on exact timing. The sol 56 marker is where I think the approach Hazcam image was taken, but only an approximate location.

Phil

Click to view attachment
kymani76
Click to view attachment
As usual Phil beat me to the update, bur anyway here is my take, color version. Track total is about 420m.
Phil Stooke
You are doing some really nice work here - for all missions! Thanks.

Phil
kymani76
Thanks Phil. Means a lot. In fact you just gave me an idea to add the fourth one. See Exomars thread post #570.
Phil Stooke
I just had an interesting and very welcome email from a reader of the forum who corrected me on my estimated sol numbers. I have updated my map with the corrected numbers and added an approximate location near the second dune - I am not sure which sol the rover arrived near that dune but we may know it after new images are released.

Corrections are always welcome - we really need as many eyes on this as possible.

Phil

Click to view attachment
Phil Stooke
The Chinese map I linked to in the main thread lets me improve my map.

Phil

Click to view attachment
Phil Stooke
My best guess for sol 75 would be right at the bottom of my map.

The query after 'c. 72' is for the date. The location is good.

Phil

Click to view attachment
kymani76
Click to view attachment
Tentative sol 75 update. I left the dates out, because I'm not sure whether UTC or Chinese time is used for counting.
I also improved on base HiRise image, although color balance is hard with these images.
Total track is 708 meters in length.
Hungry4info
New drive map from here.

Bill Harris
I give them passing marks on autonomous driving (or for careful directed driving).

--Bill
ollopa
QUOTE (Phil Stooke @ May 22 2021, 07:14 PM) *
....... The landing site is very close to the center of that ellipse and about 40 km from the initial site.

Phil

Click to view attachment



Phil: I am really struggling to reconcile the scale bar in this scene with everything else I have seen. 40 km between the dots is not what the scalebar says? Am I right? All of which is interesting because I simply don't understand why they didn't go north. If "dot-to-dot" is 40 km, then the prominent pitted cone to the NW is barely 10 km away, whereas the cones to the south are at least 20 km away, maybe a good bit more.

This stuff is way beyond my payscale: can anyone show a wider regional map with distances to key features, compared to the total traverse so far?

I realise "Why didn't they go North" is a different topic, but IMHO it has to begin with scale comparisons of other target options in the scene. We should have a HiRISE DTM of the landing site area very soon, but I am very sensitive to the fact that people who might like to weigh in here are being very *very* careful in order (I assume) to preserve valuable contacts in Utopia!
Phil Stooke
You are right, it should be more like 30 km between dots. I don't remember where the 40 km came from but it doesn't match the map. I might have been quoting some other source or just put too much Baileys on my cornflakes that morning.

I think they want to use the ground-penetrating radar on a trough about 1700 m south of the current position, which would be an interesting thing to do. Then keep going that way and hope to reach a cone.

Phil

Hungry4info
New drive map from here.
Phil Stooke
This map is very useful, but I am intrigued to find that it does not overlay the new orbiter image of the track very precisely. I will wait until we have a new HiRISE image before updating my map. The orbiter image was taken on 24 August and this map matches that except for the last point, so this map was probably made with data up to 23 August, a week prior to release.

Phil
Huguet
Amazing how detailed the orbiter get the track... a single track on Tianwen-1,.. Hirise will indeed be nice with its better resolution and seeing the 2 track path.
Phil Stooke
We have had no news on Tianwen-1 and Zhurong for a while. The rover at least, and probably the orbiter too, are entering a superior conjunction blackout period about now. Their blackout will be longer than NASA's, probably because it's the first time they have dealt with it and will want to be more conservative.

Meanwhile I wanted to show the difference between the existing map and the new Tianwen-1 orbiter image. My map is based on the published map with track and waypoints. The orbiter image shows tracks offset from it, with the offset increasing away from the lander (though the last point is close again). I suspect this is because of a small difference in the definitions of map projections between the projected orbiter image and the route map. (My coordinates are from HiRISE which opens the possibility of another offset, but in all cases I am matching to surface features using HiRISE as a standard). The maximum offset is about 10 m.

Phil

Click to view attachment.........Click to view attachment
Bill Harris
Agreed. The 'quiet spell' from Zhurong is not to be worried about. They don't have an as-established DSN infrastructure or as much experience with dealing with a faint, noisy signal.
I'm still impressed with their Rover's track. I don't know how on-course it is, but it doesn't seem to be bumping into things...

--Bill
Phil Stooke
Here is an update to my map (section 2) based on this site:

https://mp.weixin.qq.com/s/NImpyH43GAhMnF0dkpU1jA

(thanks to Andrew Jones for tweeting about it).

I have not yet corrected it to fit the tracks seen in orbital images. I will wait for a new HiRISE image to do that.

Phil

Click to view attachment
kymani76
Click to view attachment
Recently new geological map for Zhurong landing site was made available in this artilcle:
https://doi.org/10.1016/j.icarus.2021.114657.
I turned their data into this map using same symbology and adding some new IAU approved feature names.
kymani76
Click to view attachment
Sol 174 map update.
Phil Stooke
A very quick look at the end of year location. The new partial panorama is looking southeast and it leads to this position. I will post a proper map when I can get to it.

Phil

Click to view attachment
kymani76
Click to view attachment
Sol 201 update in IRG color, based on latest image from Zhurong. The rover itself has already moved a little further to the SE since.
Click to view attachment
3D perspective based on HiRise terrain model, with roughly the same perspective as published image.
Phil Stooke
I assumed the partial panorama was from the end of year date, but if it is from sol 201 I will correct my map. I am still hoping for a new HiRISE image to guide my next map. There are small differences beteen the various sources we have.

Phil

Bill Harris
QUOTE (kymani76 @ Jan 4 2022, 09:23 AM) *
attachment=50066:tianwen1...201_r001.jpg
Sol 201 update in IRG color, based on latest image from Zhurong. The rover itself has already moved a little further to the SE since.
attachment=50067:tianwen1..._3D_r001.jpg
3D perspective based on HiRise terrain model, with roughly the same perspective as published image.


They are avoiding driving over that patch of pitted terrain, but hopefully will stop for a closer look.

Nice 3D perspective!

--Bill
kymani76
QUOTE (Bill Harris @ Jan 5 2022, 03:51 AM) *
They are avoiding driving over that patch of pitted terrain, but hopefully will stop for a closer look.

Nice 3D perspective!

--Bill


Thank you, Jaka
kymani76
Click to view attachment
Preliminary sol 262 map update, based on this map found here.
I have no other source of info, but I'm sure the track distances on this map don't add up.
kymani76
Recent article characterizing first 60 sols of Zhurong traverse was published in Nature Geoscience.
While the article is sadly behind paywall it is possible to download supplemental files which include rover's track points.
Here is a comparison map of my version of traverse vs the new track points in red:
Click to view attachment

kymani76
Zhurong traverse updated with track visible in new HiRise photo ESP_073225_2055.
I also updated positions for sols 0-60 with date mentioned in previous post and manage to extend coverage to sol 75. Sols after that are approximate.
The Chinese data veers off course to the east when compared to track visible in HiRise photo, so I corrected its position to nearest point in the track.
Click to view attachment Click to view attachment
1. Whole track from the landing 2. Zoom in to the latest sol 297(?) position on 03/11/2022.
kymani76
Click to view attachment
In addition I also made elevation map with the new track plotted. It seems like Zhurong landed on "peninsula" and is headed to the "beach" now.
vikingmars
QUOTE (kymani76 @ Mar 24 2022, 05:48 PM) *
In addition I also made elevation map with the new track plotted. It seems like Zhurong landed on "peninsula" and is headed to the "beach" now.

What a great work of yours Kymani76 !
Congratulations wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif
kymani76
Zhurong rover map update. There is not a lot of new info, just the drive from sol 297 position to the (final?) position.
This last segment of the drive did not leave rover tracks visible in HiRise imagery, so its course is a bit conjectural.

BW version:

Click to view attachment
kymani76
false color IRG image version:

Click to view attachment

DEM version:

Click to view attachment
vikingmars
QUOTE (kymani76 @ Mar 10 2023, 09:56 AM) *

What a nice work!
Congratulations kymani76 wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif
Phil Stooke
Following on the discussion about maps in the main thread, I have tried to bring everything I have into one coherent set of locations. This is not yet the whole story and it will not agree with some sources but it is the best I can do at the moment.

Phil

Click to view attachment

Click to view attachment

Click to view attachment
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.