Is believing that the earth is flat any different from believing in the Higgs boson or the big bang? 

Your first reply maybe of course, one is madness the others are based on science. But how sure are you? 

Could you prove the earth is round? what "evidence" would you use? 

check out these two pieces of video, it is the same camera, the second image is actually lower in the atmosphere, but it has greater curvature. It's just a trick of the lens

https://youtu.be/4XEy2jh7Z-o?t=940
https://youtu.be/4XEy2jh7Z-o?t=1147