New York: Paying a glowing tribute to the courage and daring of India-born astronaut Kalpana Chawla, who was among seven space explorers killed in the Columbia shuttle tragedy, United States President George W Bush said "she always wanted to reach for the stars".

"None of our astronauts traveled a longer path to space than Kalpana Chawla. She left India as a student, but she would see the nation of her birth, all of it, from hundreds of miles above," an emotional Bush said at a solemn memorial for the seven astronauts at the Johnson Space Centre in Houston, Texas, on February 4.

"When the sad news reached her hometown, an administrator at her high school recalled, 'She always said she wanted to reach the stars'. She went there and beyond," he said.

"Kalpana's native country mourns her today and so does her adopted land," Bush said at the outdoor ceremony, which was attended by about 10,000 people, including National Aeronautics and Space Administration (NASA) employees.

About first-time Israeli astronaut Ilan Ramon, Bush said he "also flew above his home, the land of Israel. He (Ramon) said, 'the quiet that envelops space makes the beauty even more powerful, and I only hope that the quiet can one day spread to my country'.

"Ilan was a patriot, the devoted son of a holocaust survivor, served his country in two wars.

"Ilan, said his wife Rona, 'left us at his peak moment, in his favorite place, with people he loved'."

Hailing the daring and dedication to purpose of the seven dead astronauts, Bush asserted that the course in the face of the tragedy was to push forward in the conquest of space.

"The cause of exploration and discovery is not an option we chose. It is a desire written in the human heart. We are part of creation, which seeks to understand all creation. We find the best among us, send them forth into unmapped darkness and pray they return," Bush said from the almost same spot where former President Ronald Reagan had paid homage to seven astronauts killed in the Challenger explosion minutes after it blasted off 17 years ago.

Bush, who spoke for about nine minutes, said in a philosophical tone, "Some explorers do not return and the loss settles unfairly on some."

As the family members of some of the lost astronauts wept, Bush tried to console them, saying the sorrow is lonely, but "you are not alone. In time, you will find confront and the grace to see you through. And in God's own time, we can pray that day of your reunion will come."

Bush nearly broke down towards the end of his speech when he was addressing the children of the dead. "To the children who miss your mom and dad so much today, you need to know they love you and that love will always be with you. And you can be proud of them for the rest of your lives."

Several of the colleagues of Columbia astronauts, some who had helped train them, sobbed as the jets flew overhead in a missing man formation with one plane separating itself from the other and heading high up in the clear blue sky.

The ceremony ended with ringing of a Navy bell seven times – one for each lost astronaut. Later, Bush spent nearly 40 minutes with the families of the astronauts.

PTI