I got up this morning at 4AM to look at Mars, whose apparent size is growing and will peak in January. There are 60 arc-minutes in a degree and 60 arc-seconds in an arc-minute. Mars right now is about 10 arc-seconds in diameter. Even at 200x with my highest-quality eyepiece, it was tiny. I kind-of, sort-of, maybe saw a white polar cap and even more speculatively told myself that I was glimpsing a shadow on the disk that possibly could be a surface feature.
But probably not.