On behalf of NASA, thank you all for you participation in this heartfelt tribute to seven courageous heroes, the intrepid crew of the Space Shuttle Columbia.

Throughout our proud NASA family, the bond between those who venture into space-our outstanding astronaut corps-and those who make spaceflight possible-our dedicated scientists, engineers, safety and support personnel-is incredibly strong. Today, our grief is overwhelming.

Our duty now is to provide comfort to the brave families of the Columbia crew-the families who take so much pride in their loved one’s remarkable accomplishments.

We also have the tremendous duty to honor the legacy of these seven fallen heroes by finding out what caused the loss of Columbia and its crew, to correct what problems we find, and to make sure this never happens again.

We owe this to you, the families, and to the American people. With an uncompromising commitment to safety, we will keep this solemn pledge.

As we continue to pursue our mission goals of understanding and protecting our home planet, exploring the Universe and searching for life, and inspiring the next generation of explorers ... we hope our unceasing efforts will provide a fitting tribute to the Columbia seven.

This year, our centennial of flight, inspires us to marvel at how far we've come from the daring achievement of two bicycle makers from Ohio, Orville and Wilbur Wright, at Kitty Hawk, North Carolina. And the astronaut's ambitious research and exploration activities honored the dreams of explorers and adventurers everywhere.

Nearly three weeks ago we saw our seven astronauts head into space with smiles on their faces, and as their families have so eloquently said with "hearts full of enthusiasm, pride in country, faith in their God, and a willingness to accept risk in the pursuit of knowledge-knowledge that might improve the quality of life for all mankind."

Once in space they tirelessly worked on research aimed at fighting cancer, improving crop yields, developing fire-suppression techniques, building earthquake-resistant buildings, and understanding the effects of dust storms on the weather.

Students from around the world-our next generation of explorers-also contributed many of the science experiments that were so important to the crew.

On the morning of Columbia’s flight, I heard students from Fowler High School in Syracuse, New York proudly describe their ant colony experiment, an experiment that Columbia’s crew delighted in observing. This was one of 11 different experiments that were put together by students and kids. We will never know the results from some of Columbia’s ambitious research agenda. But be assured, however, that future astronaut crews will orbit new experiments addressing the fascinating research questions that motivated this mission.

And we pledge that students like those from Fowler High School will have similar opportunities to join our astronaut crews in these important learning adventures.

As Commander Rick Husband said, "I think one of the legacies of NASA is that you always push forward. And STS-107 is doing that on the science side-pushing human science knowledge forward." This was the work that gave the Columbia crew such unbridled joy. This was their lasting gift to us all.

Last Wednesday, as the Columbia crew was circling the globe, Kalpana took a rest from her duties to take in the stunning view of the Earth at sunset, a view that only a select group of space explorers have been privileged to witness.

Now she told us from the flight deck that the entire Earth and sky could be seen reflected in the retina of her eye. She called her crew mates over to see this amazing sight.

It is this image, the image of Columbia's crew joyfully joining Kalpana to see our beautiful planet reflected in their friends' awestruck eye ... that we will remember ... and treasure ... forever.

It is for them and their memory, that we will persevere.