AN POST HAS issued an apology after printing a spelling mistake on a series of commemorative stamps marking the 50th anniversary of the moon landing.

The mistake was on an Irish language sentence on the stamps where the word for moon, ‘gealach’, was replaced with ‘gaelach’, meaning Irish.

The result was a sentence which bascially read as: “50th Anniversary of the First Landing on the Irish”.

The mistake was spotted by a number of people on Twitter in recent days, prompting An Post to reply to a number of people with an apology.

“An Post apologises for this error and arrangements have been made to ensure that such an error does not occur again,” the tweets said.

The series of stamps featured four Nasa astronauts with Irish ancestry, Neil Armstrong, Michael Collins, Cady Coleman and Eileen Collins.

Both Armstrong and Michael Collins were crewmen on the Apollo 11 mission which landed on the moon.

Armstrong was the first to set foot on the lunar surface while Collins orbited the moon in the command module before returning to earth with Armstrong and Buzz Aldrin.