Today's NASA image may be a 30-million-to-one accident

A planned ISS transit across the Sun also caught an airplane crossing the solar disk during the same exposure.

The resulting frame contains sunspots, the ISS silhouette, and an airplane at the same instant. The photographer estimates the chance of an arbitrary solar image from that location containing both moving silhouettes at about 30 million to one.

It is exactly the kind of image that makes orbital mechanics feel tangible: one object was predicted to the fraction of a second; the other simply wandered into the frame.

The photographer had carefully timed the International Space Station transit. The airplane was pure luck.