Are there any known non-zero mass objects travelling at almost $c$ observed in the universe so far?

Question

1. Have we ever observed a body or particle with non zero mass traveling at almost $c$?

2. I'm asking this because according to relativity as an object approaches light speed it's mass approaches infinity, so the particle or object might turn into a black hole?

Answer 1

Neutrinos! they have non-zero mass and travel at ~c. Also, particle accelerators speed up electrons, protons to ~c

Answer 2

In its referential, the rocket has not gained mass, so have no reason to collapse.

Also, to have an effect on the environment you also need time (if two galaxies traverse each over fast enough, there is little effect). A (small) black hole passing close to Earth at near-c speed would have no effect as well.

Answer 3

In space, polar jets can be near-c speed, and supernovae shockwaves are relativistic as well (~10% c)