The caption in question (Stefan’s) says…

Airbus A321-200 der LTU (Kennzeichen D-ALSD), aufgenommen am 2. Januar 2005 auf dem Flughafen Düsseldorf.

which is, translated, Airbus A321-200 of LTU (registration D-ALSD), taken on January 2nd 2005 at Düsseldorf Airport.

not too difficult to get the gist of it, though, I wouldn’t think?