If a primordial black hole hits the sun…
Such an event wouldn’t be as catastrophic as it sounds, they suggest. The likelihood is that a primordial black hole with mass of an asteroid or comet would pass straight through the Sun, generating a small puff of X-rays in the process.
However, such a burst would be less even than the background rate of X-rays, so it would be impossible for astronomers to see. Instead, the collision would generate supersonic turbulence that would set the Sun ringing like a bell.
They say they are able to calculate what these oscillations would look like. They ought to be visible with today’s solar observatories as a kind of solar hiccup, so we might have seen them already.
Ref.: Michael Kesden, Shravan Hanasoge, Transient solar oscillations driven by primordial black holes, arXiv.org, May 31, 2011 [arXiv:1106.0011v1]