| Answer | Crossword Clue |
|---|---|
| NSTAR | Sky spectral type |
| RSTAR | Spectral type in the sky |
| rainbow | an arc of spectral colours formed in the sky |
| rainbows | RAINBOW, an arc of spectral colours formed in the sky |
| sundog | a small rainbow (an arc of spectral colours formed in the sky) |
| sundogs | SUNDOG, a small rainbow (an arc of spectral colours formed in the sky) |
