Marks on car rbonnet

Does anyone know what causes these marks? They seem like burn marks to me but I don't know what's causing them, and therefore how to prevent more appearing
https://ibb.co/TmJcnZy
https://ibb.co/4JmvpK5
https://ibb.co/NtKnN61
https://ibb.co/TmJcnZy
https://ibb.co/4JmvpK5
https://ibb.co/NtKnN61
0
Comments