Two local photographers, however, had convinced him that the sight of the shuttle's predawn reentry over Northern California would be especially memorable.

Just before 6 a.m., Columbia slashed the dark from horizon to horizon. Staccato flashes punctuated its passage.

The fiery pink streak left the afterglow of a holiday sparkler. It burned in Beasley's eyes long after the shuttle itself, traveling at 4 miles per second 40 miles overhead, vanished in the eastern haze.

The burly Australian astronomer could not make sense of the bright pulses of light that trailed in Columbia's wake.

His mother-in-law was puzzled too.

They might be tiles, Beasley told her. I think the shuttle normally sheds some tiles on reentry, he said. He didn't give it a second thought.

The stargazer ducked into the warm kitchen, ate a piece of toast with peanut butter, then drove to the observatory.

He had no inkling how obsessed he would become with the streak of light he had just witnessed.

*

One Columbia crew member didn't wear a space helmet, so smooth was the descent.

Too elated to bother, or perhaps too confident, three of them did not put on their orange pressure-suit gloves.

On the flight deck, shuttle commander Rick Husband, 45, chugged down three plastic flagons of saline solution to keep from getting lightheaded, a common side effect of reentry. It tasted slightly like seawater.

Pilot William McCool, 41, pored over a pre-landing checklist. Crew members Kalpana Chawla, 41, and Laurel Clark, 41, sitting behind him, watched raptly as superheated gases licked across the cabin windows.

Seated back in the mid-deck area, Michael Anderson, 43, David Brown, 46, and Ilan Ramon, 48, could not see what lay ahead.

The seven men and women were plunging out of orbit into the atmosphere over the South Pacific on the last leg of a journey that 22 years of repetition had turned into a NASA routine.

For 16 days, they had circled Earth. Now they could return.

The shock of Columbia's passage was ripping apart molecules of the thickening air. Atoms blazed furiously. Faster than a bullet, the shuttle hurtled down a tunnel of excited particles, glowing within a glow, like a firefly trapped inside a fiery neon tube.

"It looks like a blast furnace," Husband told his crew in cabin talk captured on Clark's video camera.

Gravity gently took hold inside the spacecraft. A notecard floated to the floor. At 24 times the speed of sound and 250,000 feet over Hawaii, the shuttle encountered temperatures of 3,000 degrees Fahrenheit, and the light danced even harder outside.

"It's really getting bright," McCool exclaimed.