By Roland Buerk
BBC News, Tokyo
Naoko Yamazaki is the second Japanese woman to go into space
A new record in gender equality is being set in space - for the first time four women are orbiting the earth on the International Space Station.
One of them is a Japanese astronaut, and her space flight is making people back home question the traditional roles of men and women.
In Japan she is being called the Mum Astronaut.
Naoko Yamazaki is the second Japanese woman in space but it is her family life that gets attention back home.
The space engineer's husband gave up his job with a software company to look after their seven-year old daughter Yuki, allowing his wife to pursue her ambitions.
Japanese television has been showing Taichi Yamazaki washing rice and doing the laundry, unfamiliar tasks for Japanese men.
Most still see their role as breadwinners while nearly three quarters of women leave their jobs when they have children, few to return to the workforce.
The Yamazakis say their unusual arrangement has not been easy, admitting on television they came close to separating during Naoko's long astronaut training in the United States and Russia.
But after the Shuttle launch Taichi Yamazaki said he was proud and happy that his wife had finally achieved her dream of flying in space.