The Irish postal service joined in with the excitement surrounding the 50th anniversary of the Americans leaving a few bags of poo on the moon as a proto-metaphor for the US of 2019, and released some commemorative stamps featuring Neil Armstrong and everyone's favourite trivia answer Michael Collins. Sadly, a misspelling of the Irish word for "moon" resulted in the stamps celebrating it being 50 years since the developed world first landed on the Irish.
It's your classic blown-out-of-proportion typo, with the Irish word for moon – Gealach – typed in incorrectly as Gaelach by someone at some point in the typesetting process, forming the erroneous sentence "50th Anniversary of the First Landing on the Irish" along the bottom of the series of stamps. Hilarity ensued, as you can probably imagine. People probably said funny tweets and all that. Maybe there was a good Photoshop. Could even have made the TV news. [Let's Learn Irish via BBC]