The elderly mother of an American astronaut aboard the International Space Station died in a car-train crash in a Chicago suburb on Wednesday.

NASA officials notified station flight engineer Dan Tani that his mother, Rose Tani, 90, was killed when the car she was driving was struck by a train at a crossing in Lombard, Illinois, according to Local 6 News partner Florida Today.

"We'll do everything we can to help him through a very difficult timeframe," said Eileen Hawley, a spokeswoman for NASA's Johnson Space Center in Houston.

Tani's mother was stopped behind a school bus at a railroad crossing and the gates apparently did not come down, WLS-TV, an ABC Network News affiliate reported.

She apparently went around the school bus and was hit by the train, then was taken to a nearby hospital and was pronounced dead, the TV station said.

Tani, 46, flew up to the station aboard shuttle Discovery in October and was supposed to return to Earth this month on sistership Atlantis.

The Atlantis launch is being delayed to Jan. 10 at the earliest as a result of fuel sensor problems that cropped up during two countdowns earlier this month.

A native of Pennsylvania, Tani grew up in Lombard and considers the Chicago suburb his hometown. He is an avid fan of the Chicago Cubs Major League Baseball team.

He and his wife, Jane, have two infant children, aged 3 and 1 1/2 years old. They knew there was a chance his ride home would be delayed and planned for the Christmas and New Years holidays accordingly.

Tani and crewmate Peggy Whitson, the first female commander of the station, performed a spacewalk Tuesday, inspecting two faulty parts of the outpost's critical power generation system.

"I've got to say 'Hi' to Jane, my wife," Tani said just before he reentered the station at the end of a six-hour, 56-minute excursion outside the outpost.

"I love you, and I know you're watching. So I'll be home sometime. Sometime soon I hope."

NASA still is wrestling with its fuel sensor problems, so late January is the earliest that Tani might return to Earth.

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