astronomical twilight

21 LETTERS · STARTS WITH A

astronomical twilight is a valid 21-letter word worth 31 points in Scrabble and 36 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

A1S1T1R1O1N1O1M3I1C3A1L1T1W4I1L1I1G2H4T1

1 + 1 + 1 + 1 + 1 + 1 + 1 + 3 + 1 + 3 + 1 + 1 + 0 + 1 + 4 + 1 + 1 + 1 + 2 + 4 + 1 =31 PTS

DOUBLE WORD → 62TRIPLE WORD → 93

MEANING

What does astronomical twilight mean?