On the 14th anniversary of September 11, an image taken from space of that day serves as a reminder of the physical mark the attack left on Earth.
The image was snapped by retired astronaut Frank Culbertson from aboard the International Space Station, who took video of the event. You can hear the sadness in his voice as he narrates what he's looking at:
"For New Yorkers, your city still looks great from up here," he said.
NASA's satellites also captured images of the day:
In a video posted last year, Culbertson spoke about his experiences for the Kennedy Space Center.
He also started writing letters to those on Earth soon after the tragedy. In them, Culbertson described what it was like to learn about the attack from space:
I had just finished a number of tasks this morning, the most time-consuming being the physical exams of all crew members. In a private conversation following that, the flight surgeon told me they were having a very bad day on the ground. I had no idea… He described the situation to me as best he knew it at ~0900 CDT. I was flabbergasted, then horrified. My first thought was that this wasn't a real conversation, that I was still listening to one of my Tom Clancy tapes. It just didn't seem possible on this scale in our country. I couldn't even imagine the particulars, even before the news of further destruction began coming in.
Culbertson was the only NASA astronaut on board at the time. He wrote that, "Other than the emotional impact of our country being attacked and thousands of our citizens and maybe some friends being killed, the most overwhelming feeling being where I am is one of isolation." He continued:
It's difficult to describe how it feels to be the only American completely off the planet at a time such as this. The feeling that I should be there with all of you, dealing with this, helping in some way, is overwhelming. I know that we are on the threshold (or beyond) of a terrible shift in the history of the world. Many things will never be the same again after September 11, 2001… the knowledge that everything will be different than when we launched by the time we land is a little disconcerting.
Over the days following the attack, Culbertson continued to log his feelings and describe his sense of loss and isolation. He wrote about learning of the death of a friend, Chic Burlingame, the captain of the American Airlines flight that struck the Pentagon. And he wrote about the kindness of his Russian crew mates, who provided support.
In a hopeful sign off, Culbertson wrote, "Life goes on, even in space.We're here to stay…"
Danielle Wiener-Bronner is a news reporter.