CAPE CANAVERAL, Fla. Beamed up during a radio conversation with a NASA flight surgeon, the news on Sept. 11 struck the skipper of the International Space Station much the way it did hundreds of millions on Earth.

To him it was surreal, much like a Hollywood movie, or a Tom Clancy techno-thriller.

"I was flabbergasted, then horrified," U.S. astronaut Frank Culbertson said in a letter written the day after terrorist attacks toppled the World Trade Center towers, seriously damaged the Pentagon and left a commercial aircraft destroyed and its passengers dead in Pennsylvania.

"My first thought was that this wasnt a real conversation, that I was still listening to one of my Tom Clancy tapes. It just didnt seem possible on this scale in our country. I couldnt even imagine the particulars, even before the news of further destruction began coming in."

And the news would get worse, and more personal, the very next day: Culbertson discovered that American Airlines Flight 77, which crashed into the Pentagon, was piloted by former U.S. Naval Academy classmate and friend Charles "Chic" Burlingame.

"I know so many people in Washington, so many people who travel to DC and NYC, so many who are pilots, that I felt sure that I would receive at least a few pieces of bad news over the next few days," the veteran astronaut wrote Sept. 12.

"I got the first today when I learned that the captain of the American Airlines jet that hit the Pentagon was Chic Burlingame, a classmate of mine," he added.

"I cant imagine what he must have gone through, and now I hear that he may have risen further than we can even think of by possibly preventing his plane from being the one to attack the White House," he said.

"What a terrible loss, but Im sure Chic was flying bravely to the end. And tears dont flow the same in space"

Launched to the station in August with Russian cosmonauts Vladimir Dezhurov and Mikhail "Michael" Turin, Culbertson was the only American orbiting Earth the day of the terrorist attacks.

And two letters he wrote during the three days after the tragedy give readers insight into how the news sent shock waves to an altitude of 240 miles (384 kilometers).

During what otherwise was a normal day on the station, Culbertson got word from a NASA flight surgeon during a routine private medical conference about 10 a.m. EDT (1400 GMT) Sept. 11 or about the time that the second twin tower in New York City began falling.

"The flight surgeon told me they were having a bad day on the ground," he wrote. "I had no idea"

Dezhurov could tell that "something very serious" was being discussed in the space-to-ground radio conversation and quickly floated over to Culbertson, who waved Turin over to their spot on the station.

"They were also amazed and stunned," Culbertson wrote. "After we signed off, I tried to explain to Vladimir and Michael as best I could the potential magnitude of this act of terror in downtown Manhattan and at the Pentagon. They clearly understood and were very sympathetic."

A glance at a computerized world map showed that the station was passing over southeast Canada and would soon make a sweep over New England, and just as quickly, the astronaut flew toward outpost windows.

"I zipped around the station until I found a window that would give me a view of NYC and grabbed the nearest camera," Culbertson wrote. "It happened to be a video camera, and I was looking south from a window in Michaels cabin."

The resulting video since has been beamed back to Earth and around the world. It shows a billowing tower of smoke ascending toward the heavens from lower Manhattan, drifting south and out toward over the Atlantic Ocean.

"The smoke seemed to have an odd bloom to it at the base of the column that was streaming south of the city," Culbertson said. "After reading one of the news articles we just received, I believe we were looking at NYC around the time, or shortly after, the collapse of the second tower. How horrible"

Ninety minutes later, the station passed over the continental U.S. again, this time on a ground track that took it further south, closer to the nations capital. And this time, all three aboard the station were working with one or two cameras each to try to capture images of both New York and Washington.

"There was haze over Washington, but no specific source could be seen. It all looked incredible from two to three hundred miles away. I cant imagine the tragic scenes on the ground," Culbertson wrote.

His feelings at that moment?

"Other than the emotional impact of our country being attacked and thousands of our citizens and maybe some friends being killed, the overwhelming feeling of being where I am is one of isolation."