I found a fun calculator trying to research this. An object weighing 1 microgram, travelling at 0.25c, would contain nearly 3 megajoules of kinetic energy. So yeah I guess dust wouldn’t be apocalyptic but that still wouldn’t be fun to bounce into/through.
A 1 gram rock would be “almost nuclear,” yeah, but not planet killing, and most micrometeoroids/cosmic dust is fortunately much smaller than that.
I found a fun calculator trying to research this. An object weighing 1 microgram, travelling at 0.25c, would contain nearly 3 megajoules of kinetic energy. So yeah I guess dust wouldn’t be apocalyptic but that still wouldn’t be fun to bounce into/through.