HUNTSVILLE, Alabama -- Think being a NASA astronaut is hard? Try being a payload operations director at Huntsville's Marshall Space Flight Center.

Astronaut Timothy J. "TJ" Creamer is learning it's hard on the ground, too, as he tries to do what no astronaut has done. Creamer is training to be an operations director at Marshall's Payload Operations Center.

The center is where ground controllers work around the clock, seven days a week, with astronauts performing all of the science on the station orbiting 200 miles above the Earth. They work in a locked, secure room filled with computer stations, stacks of monitors and screens where live video of Earth as seen from the space rolls constantly.

"We spend quite a long time in training to go fly on the space station," Creamer told reporters Wednesday. "Those operational hands-on (lessons) we learn over many years. Interestingly enough, that's the easy part.

"The hard part," Creamer said in a sentence to warm any manager's heart, "is doing the coordination to make that easy for the crew. That's the big challenge -- making sure we get all the right players, all at the right time, all in the right direction."

Creamer flew more than 65 million miles in space while living on the station for five months in 2010. He's still an astronaut and hopes to fly again, but next week Creamer will qualify as a payload operations director, too.

As an astronaut, Creamer knows what works in space and what doesn't. That helped make him a quick study, and he's brought that knowledge to the control room. "We have our normal process for training someone: reading, simulations that we do, roundtables ...," payload operations director Stephanie Dudley said Wednesday. "We still do that. But, for TJ, it's a compressed schedule. He's a natural. He's been good at it since Day 1."

It's important work done in Huntsville, Creamer said. "This is the premier center for doing space research," he said of Marshall. "We can learn a lot about how to better our lives on Earth because of the stuff we're doing on orbit. This is the place to set that up."

What makes space science special? Creamer said astronauts can remove a key variable in their experiments: gravity. Creamer mentioned studies of combustion, where perfectly spherical flames in space allow experiments impossible on the ground, and research into cancer cells, which grow in space without gravity impeding their processes.

"You have a perfect cancer cell, growing perfectly, and now you're able to examine the perfect processes that you want to perfectly interrupt," Creamer said.

How different is talking to the station from Marshall from talking to Marshall from the station? Not that different, Creamer said, because, "Operations is pretty much operations." But station crew members do seem to "get kind of excited to hear my voice and know I'm here," Creamer said. "It's a bit of a brotherhood, sisterhood thing that's kind of fun to deal with."

And how do the center's other operations directors like having an astronaut among them? Dudley loves it, because she knows the opportunities astronauts have. "An astronaut wants to come and do my job," Dudley said. "How cool is that?"