| Clue | Source | Date |
|---|---|---|
| Cool red giants | New York Times | 01 Dec 2019 |
| Cool red giants | ||
| Some red giants | New York Times | 12 Aug 2016 |
| Some red giants | ||
| Red giants in the night sky | ||
| Certain red giants | ||
| Red giants with zirconium oxide in their spectra | ||
| Red giants | ||
| Some red giants | ||
| Cool red giants | ||
| Some astral types | ||
| Spectral types |