Wanted: healthy women, aged 25 to 40. Must be willing to stay in bed for two months. The French need not apply.
It is a strange advert for the European Space Agency (ESA) to take out, but one it desperately hopes will get it out of a fix.
A call for volunteers to test the effects of weightlessness on women has so far attracted hundreds of applications from French women, but hardly any from elsewhere.
"Most of the data we have are based on men, so we need to get more on how being in space effects female physiology," said Peter Jost, a doctor at ESA's research lab in Noordwijk, the Netherlands.
"But space missions are generally multicultural endeavors, so we're keen to get a mix of nationalities too."
The experiment, known as the Women International Space Simulation for Exploration study, will be more than just a two-month bed rest.
To mimic the effects of weightlessness, women must lie in beds tipped at an angle of six degrees.
"You have to perform every activity of daily life in that lying down position with your feet slightly above your head," said Jost.
The delicate issue of what to do with one's waste is solved by a low-tech bedpan.
The good news is that there is a shower -- a plastic coated bed in a shower room.
Nurses will be on hand to move volunteers, ensuring their feet never drop beneath their heads.
Women interested in applying should know that getting a place on the study is no cake walk.
Only around 3 percent of those applying are expected to pass the stringent medical and psychological examinations.
"It's not quite as tough as astronaut selection, but it's getting that way," said Jost.
Given the lengthy examinations needed first, ESA scientists say that if they do not get more European women applying before Christmas, the start of the experiment might well be jeopardized.
"We need women as soon as possible," Jost said.
Women account for around 10 percent of those who have ventured into space, but the numbers are growing.
NASA's astronaut core is now 20 percent women.
The weightless conditions of space can cause severe physiological changes, including bone and muscle loss.
But the subtle differences that exist between men and women are still not particularly well understood.
The ESA experiment will compare the effects of different nutritional supplements and bed-bound exercise regimes on the prevention or retarding of bodily deterioration.
The mass of applications from French women is due to the site of the hospital where the experiment will be carried out, the Rangueil hospital in Toulouse, south west France.
"It's getting to the stage where we're seriously thinking about taking adverts out in other countries," Jost said.
Details of how to apply can be located at the Web site, www.medes.fr/Home.html.