@palaeokatie I cannot find a download of the Channel 4 Walking in Time episode that covers this, aired Sept 2016. If anyone can I would love to know. Also I had no idea that impacts like this leave a gravitational signature (if I’ve understood less density equals lower gravitational readings). That the this was over a billion years ago makes it even more fascinating! Also learned that Scotland was actually near the equator at that time…anyway we can use this in the argument for independence lol!