Two days into one of the most ambitious shuttle science missions in years, the commander of the shuttle Columbia said his dual-shift team has encountered remarkably few problems and that "things are going really well."

"Columbia is in great shape and working absolutely perfectly and the experiments are working very well also," commander Rick Husband told CBS News in an interview from orbit. "So I'd say we're batting at least a thousand for starters."

Laurel Clark, a Navy physician making her first flight, said working in Columbia's roomy Spacehab module is a breeze.

"I would call it anything but cramped," she said. "In fact, I'm still getting my space legs, but I use them even more when I have to go back to Spacehab because there's so much room back there. Which is an advantage because when many of us are working there's room to get around and do the things we need to do.

"The experiments are going wonderfully," she added. "We've been busier than I even imagined, since things really do take longer up here. But we've already activated most of the experiments and they're doing very well, the ground teams are getting excellent data and we're very happy."

Columbia is loaded with more than 80 experiments in a variety of disciplines, ranging from medicine and biology to materials science, basic physics and student research involving bees, spiders, silkworms, ants and fish.

Other experiments mounted in the shuttle's cargo bay are part of investigations to characterize the ozone layer, the sun's energy output and the transport of dust particles over the Mediterranean basin. Ilan Ramon, the first Israeli in space, is on board in part to operate the multispectral MEIDEX dust camera.

So far, the weather hasn't cooperated, but Ramon said he's been busy nonetheless. So busy, in fact, "I didn't even have a chance to think about the Sabbath."

"I'm secular and I didn't get any special permission (to work on the Sabbath)," he said. "I'm here with special teammates, crewmates, and I'm working every day. The only thing I did have is a kiddush cup, but I even missed that yesterday, for Friday. I hope I'll do it next Friday."

Asked about the significance of Israel becoming the 30th nation to put a representative in space, Ramon had remarkably little to say.

"I sure thought about it before getting to space, but the last two or three day we were real busy getting our (space) legs on and I didn't have a chance to think about it up here," he said. "I'm sure I will have the chance later on."

As for voting in Israel's national elections Jan. 28: "I haven't voted and I will not vote. I will send my father back (from the U.S.) to vote on behalf of me."

Columbia's crew features four first-time fliers: Ramon, Clark, pilot William McCool and David Brown. Clark said the biggest surprise for her so far was "how much the ascent felt just like the simulation."

"I guess the second one that I noticed immediately was, obviously everything floats, the zippers and all the belts that have D-rings that we hold things down with are always floating and hitting each other and jingling and its makes this beautiful tinkling music in the background all the time," Clark said. "It just caught me off guard and it was beautiful."

At an afternoon status briefing, flight director Robert Castle, representing NASA's mission operations directorate, said Columbia is operating with "virtually no anomalies" and that the crew's power margins remain positive for a full-duration 16-day mission.

NASA mission scientist John Charles said the first human life sciences data takes were made today, including multiple blood draws and the collection of urine and saliva samples to support metabolic studies, including research to learn more about why astronauts lose bone mass in weightlessness."

"Our experiment is looking at what we call calcium kinetics, which is the movement of calcium through the body," said investigator Scott Smith. "The way we do that is we use tracers, we give a special form of calcium to the astronauts, they take one of these orally, one is infused intravenously, and we then collect samples and trace the movement of calcium through the body.

"Bone changes, as we all know, are very important during spaceflight, that is, the loss of bone is a significant health concern for astronauts. The amount of bone that's lost in a short-duration flight, in a few weeks, really is not that significant. It's actually very hard to measure. So what we look at is the change in calcium and we look at the change in markers of biochemistry, things that we can measure in the blood and in the urine that tell us what the bones are doing."

As it turns out, bone loss in people who have been recently paralyzed is similar to what astronauts experience during long-duration space flights. Somehow, in both cases, the body "understands" bone mass is no longer needed and metabolic changes are the result. Exactly what triggers those changes, and how they might be nullified or even reversed, is not yet known.

But barring implementation of technology that simulates gravity in space, resolving this issue is critical before humans can begin the long-duration flights needed to someday explore the solar system.

"Ultimately, our goal is to help mitigate or reduce if not eliminate the bone loss during spaceflight," Smith said. "What we're doing on this flight will help us understand the early changes during spaceflight, what happens during the first days and weeks of weightlessness and how the body adapts to that.

"We have done some preliminary studies on Mir," he said. "We're looking forward, hopefully, to be able to do these studies on the (international) space station to look at the time course of changes in calcium metabolism over time."

Later today, the Columbia's crew will begin work with an experiment to light small fires in a high-tech combustion module to learn more about how flames develop and propagate in the absence of gravity.

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