Going over the edge of the world
The sounds of the termination shock. Enjoy it while it's still awe-inspiring (i.e. before someone makes an action movie called Termination Shock about a hard-bitten astronaut cop with one last case to crack before retirement.)
The Japanese for "termination shock" is 末端衝撃波面 ("Edge shock wave boundary") or 音速面 ("Sound speed boundary", I assume because the termination shock is where the solar wind finally slows down to subsonic speeds). I learnt this from a rather awesome E->J dictionary of astronomy terms hosted by the Japanese translation of the Astronomy Picture of the Day.