Columbia is scheduled for liftoff Thursday on a 16-day science research mission. Photo: Justin Ray/Spaceflight Now

Under a now-familiar blanket of heightened post-Sept. 11 security, engineers are readying Columbia for blastoff on the 113th shuttle mission - STS-107 - at 10:39 a.m. Thursday at the opening of a 2.5-hour launch window. Ideal weather is expected.

The goal of the flight is to carry out space station-class research in a variety of disciplines, ranging from biology to medicine, from materials science to pure physics and technology development, research that cannot yet be accommodated on the still-unfinished international space station.

"We're all familiar with the overhead required for continuing station operations, especially with a crew size of three," said U.S. mission scientist John Charles. "Missions like STS-107 were inserted in the manifest to do science as if they were on the space station.

"This is simulated space station science, although the science itself stands on its own right, with the goal of keeping the scientists who are involved in this kind of activity engaged and productive and moving forward until the space station can assume the leading role in research."

On board will be commander Rick Husband, pilot William "Willie" McCool, Indian-born flight engineer Kalpana Chawla, physicians David Brown and Laurel Clark, payload commander Michael Anderson and Israeli air force Col. Ilan Ramon.

Joining them will be 13 rats, eight garden orb weaver spiders, five silkworms and three cocoons, four Medaka fish eggs that will develop in space, three carpenter bees, 15 harvester ants and an assortment of fish.

The animals and insects are subjects of experiments, many of them designed by students, to learn more about how weightlessness affects growth and behavior.

To maximize their time in orbit, the astronauts will work around the clock in two 12-hour shifts. Husband, Chawla, Clark and Ramon will make up the "red shift," working what amounts to a day shift in the United States, while McCool, Brown and Anderson will work the overnight "blue shift."

"STS-107 is a dual-shift, 16-day dedicated science mission," said lead flight director Kelly Beck. "This flight's going to provide multiple NASA centers, the international community as well as universities and schools throughout the world a very unique opportunity to perform a lot of science and a lot of research and technology demonstrations. So we're really looking forward to this flight."

Payload specialist Ilan Ramon. Photo: NASA

Ramon's presence on the crew has generated more interest than usual in security precautions. But NASA managers insist the policy implemented last year in the wake of the Sept. 11 terrorist attacks in New York and Washington is essentially unchanged.

Fighter jets will be patrolling an FAA-mandated no-fly zone extending 30 miles in all directions from pad 39A, powerful military radar systems and reconnaissance planes will be scanning the skies and the Coast Guard will be patrolling off shore.

But all of that is pretty much standard procedure in the post-Sept. 11 climate. NASA security chief David Saleeba, a former Secret Service agent, said his team has been "tweaking and re-tweaking" security precautions in recent weeks, but no major changes have been implemented.

"You're not going to see that much difference in the area of security for this launch than you did for the last several launches," Saleeba said. "We're trying to still maintain an openness within the agency while still maintaining an appropriate level of security."

Even so, based on the world climate today, "I would be foolish to try to make you believe that the presence of an Israeli astronaut on this flight would not make it a higher profile flight," Saleeba said.

"It's unfortunate that that is true, it shouldn't be," he said. "He's first and foremost and astronaut and a scientist. And on a secondary note, he's Israeli. But we fly international people, people from all over the world on many of our flights. But because of the fact that he is Israeli, and what's going on in the world today, it's a natural assumption that this may be a higher profile flight."

But Saleeba said there have been no credible threats against the space shuttle since Sept. 11, including Columbia's mission.

"We always have concerns about these missions because the shuttle is a fairly prominent symbol of American technology," he said. "But no, we don't have any threats right now that we're overly concerned about."

In a departure from past missions, local law enforcement personnel are on watch and extra security personnel and barricades are in place at a Cocoa Beach hotel where Israeli dignitaries, researchers and family members are staying. A spokeswoman for the Brevard County Sheriff's Department described the precautions as unprecedented.

"I really think the NASA security people are taking care of all the security issues very good, I have all the confidence they're doing their job for the best of all of us and we really feel, all the crew, including me, we feel that we are being treated as properly as we could," Ramon said in an interview with CBS News.

"I believe the post-Sept. 11 (aftermath) put the world in an unusual and new situation," he said. "Everybody is more focused on the risks wherever they could be. It's obvious the media is trying to concentrate on this risk. But again, I think the NASA security people are doing their job."

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