Frost

Last night the temperature outside our house fell to below -3C and frost was deposited on many surfaces.  Much to my surprise there was a very heavy frost on the outside glass surface of our new doors, but none on the inner glass, which felt quite warm.  Obviously the new doors have exceedingly good double-glazing.  I thought the frost crystals on the glass were pretty and would make a very good blip, however, now looking at them, I am not sure that I was correct.