Cape Canaveral, Fla. ? In what might embarrass less adventurous souls, astronaut Koichi Wakata is returning to Earth with the underwear he kept on for a solid month during his space station stay and scientists will check them out.

They’re experimental high-tech undies, designed in Japan to be odor free.

The Japanese spaceman described his underwear test Thursday as shuttle Endeavour and its crew aimed for a touchdown the next morning. The astronauts released some mini satellites, their final job before today’s re-entry, and said it was time to come home after more than two weeks aloft.

Wakata has been off the planet for 4 1/2 months.

“I haven’t talked about this underwear to my crew members,” Wakata said in an interview with The Associated Press, drawing a big laugh from his six shuttle colleagues. “But I wore them for about a month, and my station crew members never complained for about a month, so I think the experiment went fine.”

The Japanese underwear, called J-Wear, is a new type of anti-bacterial, water-absorbent, odor-eliminating clothing designed for space travel. The line includes shirts, pants and socks as well. Wakata tested all of them during his mission; he had four pairs of the silver-coated underwear, a cross between briefs and boxers.

“We’ll see the results after landing,” Wakata said.

J-Wear is billed as being antistatic and flame retardant, which is especially important for spaceship wear. The cotton and polyester clothes are also seamless, making them lighter and more comfortable, according to the Japanese Space Agency. The goal is “comfortable everyday clothes for life in a spaceship.”

Another Japanese astronaut wore some J-Wear items during a shuttle flight last year, but had only 16 days in orbit to try them out.

NASA’s space station program manager, Mike Suffredini, stressed the importance of testing new products, especially those aimed at improving astronauts’ quality of life. There’s no way to wash clothes in space. Station residents simply ditch dirty outfits, along with other garbage, in no longer needed cargo ships that are sent plunging in flames through the atmosphere.

“Eventually, we’re going to do exploration. We’re going to go to the moon. We’re going to go beyond the moon someday, and little things like this will seem like really, really big things when you’re far away from Mother Earth,” Suffredini said.