Oops, it doesn't look like 'air and space museum day' is a national day..

Other days

ruby

Ruby Day
book

Book Day
brow

Brow Day
singles

Singles Day
pampering

Pampering Day
kiss a ginger

Kiss A Ginger Day
hoodie

Hoodie Day
lisp

Lisp Day
hannah

Hannah Day
stud

Stud Day