What did the COBE satellite find that suggests that the big bang explosion occurred?

Answer 1

The CoBE (Cosmic Background Explorer) proved, beyond any doubt, that the spectrum of the CMBR is that of a black-body of temperature 2.7K -- some researchers were finding slight differences from this. The VERY minor anisotropies (about one part in 10,000) found in the CMBR are consistent with matter clumping in the early Universe, just enough to produce galaxies.

Note that WMAP and the Planck Probe have done even more precise measurements, and continued to get results consistent with CoBE.

Answer 2

The COBE satellite detected the cosmic microwave background radiation, which is residual thermal energy from the Big Bang explosion, providing strong evidence for the Big Bang theory. This radiation is uniform in all directions, supporting the idea that the universe originated from a single point in a rapid expansion event.