while not many people want to touch Clark Kent, those that do don't notice anything strange, so it can't be heat-related or a super-rigid material. Plenty of people shed skin cells, and sweat during the day. Since Superman is made up of different materials (or at least his eyeballs are), whatever he sheds has to be easy for a slow-moving object to move through, but turn impenetrable on impact. It has to, therefore, be a non-Newtonian fluid. Many non-Newtonian fluids can be manipulated quite easily if they are touched slowly and without much force. A person standing on one would sink into it. However, give the fluid quick push, and it become rigid, and resistant to force. A person running on such a non-Newtonian fluid can make it across without any trouble, since the impact of their feet makes the fluid stiffen and support their weight.
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A person standing on one would sink into it. However, give the fluid quick push, and it become rigid, and resistant to force. A person running on such a non-Newtonian fluid can make it across without any trouble, since the impact of their feet makes the fluid stiffen and support their weight. Likewise, someone slowly and carefully touching Superman wouldn't notice anything amiss, while a sudden impact would make his non-Newtonian fluid aura turn impenetrable. Interestingly, custard is a non-Newtonian fluid. This theory could be tested if anyone were to lick Superman and see if he tastes sweet. Volunteers? Likewise, someone slowly and carefully touching Superman wouldn't notice anything amiss, while a sudden impact would make his non-Newtonian fluid aura turn impenetrable. Interestingly, custard is a non-Newtonian fluid. This theory could be tested if anyone were to lick Superman and see if he tastes sweet. Volunteers?