A giant leap is about to be made for womankind.
When space shuttle Discovery blasts off Tuesday, a woman will be sitting in the commander's seat. And up at the international space station, a female skipper will be waiting to greet her.
It will be the first time in the 50-year history of spaceflight that two women are in charge of two spacecraft at the same time.
This is no public relations gimmick cooked up by NASA. It's coincidence, which pleases shuttle commander Pamela Melroy and station commander Peggy Whitson.
"To me, that's one of the best parts about it," said Melroy, a retired Air Force colonel who will be only the second woman to command a space shuttle flight. "This is not something that was planned or orchestrated in any way."
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Indeed, Melroy's two-week space station construction mission was originally supposed to be done before Whitson's six-month expedition.
"This is a really special event for us," Melroy said. "... There are enough women in the program that coincidentally this can happen, and that is a wonderful thing. It says a lot about the first 50 years of spaceflight that this is where we're at."
Whitson — the first woman to be in charge of a space station — arrived at the orbital outpost on a Russian Soyuz spacecraft on Oct. 12. She flew there with two men, one a Russian cosmonaut who will spend the entire six months with her.
Before the launch, an official presented her with a traditional Kazakh whip to take with her. It's a symbol of power, Whitson explained, because of all the horseback and camel riding in Kazakhstan.
Smiling, she said she took the gift as a compliment and added: "I did think it was interesting though, that they talked a lot about the fact that they don't typically let women have these."
At least it wasn't a mop. The whip stayed behind on Earth.
Eleven years ago, just before Shannon Lucid rocketed to the Russian space station Mir, a Russian space official said during a live prime-time news conference that he was pleased she was going up because "we know that women love to clean."
"I really haven't heard very much like that at all from the Russian perspective," Whitson said in an interview with The Associated Press last week. "Russian cosmonauts are very professional and having worked and trained with them for years before we get to this point, I think makes it better because then it doesn't seem unusual to them either."
"So I think I'm luckier. Shannon was probably breaking more barriers in that way than I have been," added Whitson, who spent six months aboard the space station in 2002.
Melroy, 46, a former test pilot from Rochester, N.Y., and Whitson, 47, a biochemist with a Ph.D. who grew up on a hog farm near Beaconsfield, Iowa, are among 18 female astronauts at NASA. Seventy-three astronauts are men.
What's more, Melroy is the only female shuttle pilot left at NASA. Eileen Collins, who in 1999 became the first woman to command a shuttle, quit NASA last year. Susan Kilrain, who flew as a shuttle pilot but never as a commander, resigned in 2002. Both have children.
Melroy and Whitson are married to scientists, and neither has children.
This will be Melroy's third shuttle flight; her first two were as co-pilot. She became an astronaut in 1995, Whitson in 1996.
Their 1 1/2 weeks together in orbit will be extraordinarily busy and the work exceedingly complex. The shuttle is hauling up a pressurized compartment that will provide docking ports for the European and Japanese laboratories that will be launched over the next few months.
The 10 space fliers, seven of them men, will attach the new compartment, named Harmony, to the space station and move a girder and set of solar wings from one spot to another. Five spacewalks will be conducted, including one to test a repair technique on deliberately damaged shuttle thermal tiles.
Melroy and Whitson will oversee it all.
Their male crewmates offer plenty of praise. One of them — Daniel Tani — will report to both. He'll fly up on Discovery and swap places with an astronaut who has been living on the space station since June, and stay on board until another shuttle comes up in December.
"The joke has been that my life recently is run by women," said Tani, who is married with two young daughters. "I have two bosses at work. I've got three bosses at home and as it was pointed out recently, much of the time when we're running the robotic arm, I'm the assistant to Stephanie" Wilson, a shuttle crew member.
"So far, I've survived all of it so we'll see if I can get through the next couple months," he said with a laugh.
It's more of a novelty for Melroy's co-pilot, Marine Col. George Zamka. He never served with or for a woman in any of his military flying units.
"I understand it's a wonderful thing for young women to see Pam flying, but in terms of her, I look at her as an individual with some tremendous skills," Zamka said.
Melroy and Whitson said they don't know of any men — American or Russian — who would refuse to serve on their crews. It wasn't always that way at NASA, which didn't accept women as astronauts until 1978.