Astronaut's Mom Dies While He's in Space

This story was updated at 4:04 p.m. EST.

HOUSTON (AP) - An American astronaut aboard the international space station went back to work Thursday even as he grieved for his mother, who was killed a day earlier when a train struck her vehicle..

Rose Tani, the 90-year-old mother of astronaut Daniel Tani, died Wednesday in the Chicago suburb of Lombard.

Daniel Tani, 46, is believed to be the first American astronaut to lose a close family member while in space, NASA spokeswoman Nicole Cloutier said.

A NASA flight surgeon and Tani's wife informed him of his mother's death Wednesday evening in a video conference call, Cloutier said.

On Thursday, Tani was moving ahead with his normal work on the space station, including working on some science experiments, she said.

Police said Rose Tani stopped behind a school bus at a railroad crossing and then drove around the vehicle, bypassing the lowered crossing gate. The train struck Tani's vehicle on the passenger side and pushed it down the tracks before stopping.

Paramedics took Rose Tani to a hospital, where she was pronounced dead.

"He is obviously pretty sad," the astronaut's brother, Richard Tani, said in Thursday's edition of the Chicago Sun-Times. "He was pretty close to her. We are all close to her. She was loved by everyone."

Daniel Tani was supposed to fly home aboard Atlantis on Wednesday, but the shuttle's flight was postponed until January due to a fuel gauge problem. The earliest he could return to Earth at this point is late next month.

"Before anyone launches, they understand that unfortunate things could happen and that's unfortunately part of the difficulties, hardships and risks of space flight," NASA spokesman Jim Rostohar said in Thursday's edition of the Chicago Tribune.

NASA spokeswoman Eileen Hawley told the Houston Chronicle that Tani's duties will be postponed or handled by his crewmates, station commander Peggy Whitson and cosmonaut Yuri Malenchenko.

"Something like this is always very personal, so it will depend on his wishes," Hawley said.

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