NASA 9/11
Smoke pouring out of the World Trade Center on September 11, 2001 was visible from space. NASA

NASA Astronaut Frank Culbertson has a fairly uncommon answer to where he was when the attacks of September 11, 2001 happened -- he was aboard the International Space Station, and he has the astonishing 9/11 footage to prove it.

Culbertson said in an interview with NASA that he was relaxing with a Tom Clancy novel when he heard reports of the attacks on New York. The wall between the events in the book and the real world seemed to collapse, Culbertson said. Soon he had undeniable evidence that what he had heard was no fiction: a plume of smoke, from his vantage point a grey wisp, twisting out of Manhattan.

Once I saw it out the window, we took video as the second tower was collapsing. I didn't know exactly what was happening, but I knew it was really bad because there was a big cloud of debris covering Manhattan, Culbertson said. That's when it really became painful because it was like seeing a wound in the side of your country.

Culbertson later described the psychological horror of watching the September 11 attacks from such a remote place.

It's horrible to see smoke pouring from wounds in your own country from such a fantastic vantage point, he told NASA. The dichotomy of being on a spacecraft dedicated to improving life on earth and watching life being destroyed by such willful, terrible acts is jolting to the psyche, no matter who you are.

Here is the harrowing video: