Hey!
I've recently tried searching for currencies depicting auroras (borealis/australis) and noticed there's no tag specifically for it.
What's worse, some pages only use the term “aurora”: N#3451 , N#158084, N#231819 .
…and some pages only use “northern lights” instead: N#201753 , N#202686.
So I feel like an “Aurora” tag would be a good inclusion for searchability, maybe under the “Natural phenomenon” tag.
Cheers!