My career at NASA included working at the Johnson Space Center in Houston, so I closely followed the flights of the space shuttle. A fortunate opportunity came during the end of flight STS-93 on July 27, 1999, a mission commanded by Eileen Collins aboard the space shuttle Columbia. I noted that the entry ground track showed passage right over south Texas and because of the clear night, it would be particularly brilliant.
Over the Indian Ocean, about an hour earlier, Columbia was upside down, relative to Earth, facing backward to the direction of flight, and conducting a two-minute burn of the orbital maneuvering engines. Traveling west to east, the engines only slowed Columbia by a couple of hundred miles per hour from the 17,500 mph orbital velocity.
After the burn, Columbia then tipped very slowly forward until it was at the proper angle for atmospheric entry. The slightly slower velocity allowed the vehicle to drop a little lower where it began to enter the atmosphere just past Hawaii. Slowly, inexorably, the nose, belly tiles, and wing leading edges begin to warm from the friction. This hyper-velocity mass impacts and strips atmospheric air molecules of their electrons, and they become highly luminescent plasma. By the time Columbia reached the west coast, people on the ground could see the trail of plasma particles.
As Columbia approached the southwest United States, she was already performing roll-reversals -- rolling left and then right to bleed off energy, much like a snow skier traversing downhill.
On that warm Houston night, about 10 p.m., my wife and I stood in our back yard with one eye on the western skies and one on the television through the living room window showing the flight path.
We waited. Then, appearing over the neighborhood roofs was a bright shimmering gold streak extending across the sky from the west. Leading the streak was an intense golden star-like glow. That was Columbia, with five people on board, now traveling at 12,000 miles per hour. The trail was almost like a jet airliner contrail, but instead of water vapor were trillions of trailing ions created by Columbia ripping through the ionosphere. Even after she passed over the eastern horizon, the stream of glistening golden plasma still extended almost all the way across the sky.
We watched for a few minutes as Columbia finally disappeared to the east. By the time we went inside, the tracking station at the Kennedy Space Center in Florida had picked up Colombia on radar. Commander Collins flew this gliding aircraft over the Center, turning around on the heading alignment circle, and gently touched down on runway 33, a 15,000 foot, extra-wide concrete strip. She only needed a little less than half of the runway to stop.
There are a few videos on line of a space shuttle entering the atmosphere at night, but as in the launch, the brilliance is not evident in video.
It is possible, but unlikely, that some in the United States will see Atlantis enter the atmosphere during nighttime hours unless Mission Control brings Atlantis in over the continental U.S. Atlantis is scheduled to land about 7:06 a.m. EDT. Future space flight will likely land in the oceans so there is little chance a generation of Americans will ever experience this astounding event; if you have not witnessed a reentry by now, you have missed a cross-country fireworks show.
Gray Fox spent 25 years as an aerospace engineer for NASA
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