I am working on the Tianwen-1/Zhurong section of my book, hoping to created an accurate map of the whole traverse. I think by now, a year without any movement of the rover, we can consider the surface mission over.
But trying to nail down which sol the rover was at each location is very difficult. Consider these two published maps:
Click to view attachmentThe map on the left is from:
Ding, L., Zhou, R., Yu, T., Gao, H., Yang, H., Li, J., Yuan, Y., Liu, C., Wang, J., Zhao, Y.Y. and Wang, Z., 2022. Surface characteristics of the Zhurong Mars rover traverse at Utopia Planitia. Nature Geoscience, 15(3), pp.171-176.
https://doi.org/10.1038/s41561-022-00905-6The map on the right is from:
Chen, R., Zhang, L., Xu, Y., Liu, R., Bugiolacchi, R., Zhang, X., Chen, L., Zeng, Z. and Liu, C., 2023. Martian soil as revealed by ground-penetrating radar at the Tianwen-1 landing site. Geology, 51(3), pp.315-319.
https://doi.org/10.1130/G50632.1These are both good papers in top journals, but their maps do not agree.Look at the point labelled 59 on the left. It corresponds with the point labelled 60 on the right.
A one sol difference might be the result of starting the mission with landing on sol 0 or sol 1 in different sources, and there does seem to be confusion about that. In the early sols I thought the landing was on sol 0, but I don't recall where that came from. The Ding paper, which includes a table of activities for sols 1-60, uses sol 1, and I will be working with that now.
A one sol difference also might arise from the 'park, sleep, study, drive' sequence we see on NASA rovers. Curiosity, for instance, might drive and park for the night on sol 1000, make science observations on the next morning and then drive again, putting sol 1001 observations and target names at the sol 1000 location. All us poor rover mappers have had to deal with that.
But then look at the twisty bit of the path labelled 28-29-30 on the left. The corresponding points on the right are 30-31-33.
It is very unfortunate that the mission team have not released an official map so that everyone - Chinese scientists as well as everyone else - can work with the same data.
I am going to try some contacts in China.
Phil