| Clue | Source | Date |
|---|---|---|
| High-energy particle that moves almost as fast as light | Wall Street Journal | 24 Nov 2025 |
| My! Corsica suffered from having highly penetrating beam from space (6,3) | ||
| Source of particles from outer space | ||
| Coy racism troubled tiny space-traveller (6,3) | ||
| Particle from outer space | USA Today | 26 Sep 2022 |
| Funny comics in school produced by traveller at the speed of light | ||
| Source of some ambient radiation | Newsday | 24 Mar 2016 |
| Space traveler? | ||
| It doesn't swim | ||
| One field for space medicine. |