NosyNed writes:
The big bang itself, of course, has excellent observations in support of it. It has been observed.
The observational evidence for the Big Bang is strong, but I don't think direct observation is part of the evidence. I think for the first two or three hundred thousand years matter was ionized and the universe was opaque, only becoming transparent after the ionized hydrogen atoms picked up electrons. I might be off on the timescale and the details, but I'm pretty sure I've got the general sense of things right. It might be interesting to find the furthest back we've observed so far. My guess would be about 13 billion years.
--Percy