The Moon was just past first quarter, and a pretty nice target. He had it all set up, and noticed an airplane headed toward the Moon in the sky. He didn’t have much time, but luck favors the well-prepared. He was able to snap this spectacular shot:
Holy wow! I’m no plane spotter, but a bit of searching makes me think that’s a Delta 767. At 1/640th of a second the plane shows a bit of blur at such high magnification, but that only adds to the sense of drama in my opinion. And I love the distortion of the Moon from the hot exhaust of the jets! Note how crisp the Moon looks otherwise; like I said, AP makes incredibly good optics.
A little math will help reveal just how good his timing was. Note that the plane is very roughly the same apparent size as the Moon. There are variants of the 767 with different lengths, but 50 meters is close. A typical cruising speed is 600 kilometers per hour, which is 170 meters per second. That means the plane travels its own length in about one-third of a second.
Now think about how perfectly timed this photo is. If Luxemburg had been off by literally half a second he might have missed the shot. I've seen a lot of shots of airplanes near the Moon, but this is the finest one in memory. Very cool.