It was one of those mornings when the sky seems to be the brightest blue and the air is cold, clear and crisp. But what happened 10 years ago that morning forever changed the lives of the families of seven astronauts, and is now marked by the question, where were you when the Space Shuttle Columbia broke apart over the skies of East Texas?

NASA's marking the 10-year anniversary of the Columbia space shuttle explosion today by honoring the seven astronauts who died when the spacecraft was disintegrated over Texas. The space agency's holding a public memorial service today at Florida's Kennedy Space Center.

The North Texas University where Kalpana Chawla earned her master's degree in aerospace engineering will mark the anniversary of her death at 7:59 a.m. Friday, the moment when NASA Mission Control lost radio contact with the shuttle as it broke up over Texas.

In front of Kalpana Chawla Hall, a residence hall on the UTA campus, students will release biodegradable white balloons in Chawla's memory.

Chawla was part of the seven-member crew that died in the disaster.

We'll certainly never forget.

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