NASA will spend a total of £340248, equivalent to Sh44.9 million for 24 volunteers to spend two months in bed.
This means each participant will pocket Sh1.8 million.
The volunteers will help scientists reduce the effects of space travel on astronauts.
The 24 men and women will be split into two groups and housed in a single room where they will be required to do everything lying down – from eating to going to the toilet.
The volunteers will be kept in beds with the head end tilted just below horizontal and must ensure one of their shoulders is touching the mattress at all times.
As blood flows to their heads and muscle is lost from underuse, researchers will investigate changes and test techniques from diet to physical exercise.
The joint study, funded by the European Space Agency (ESA) and NASA, is taking place at German Aerospace Centre (DLR).
Using the facility’s short-arm centrifuge, a selection of the study’s participants will be spun to encourage blood to flow back towards their feet and allow researchers to understand the potential of artificial gravity in combating the effects of weightlessness.
A team of medical, psycho-therapeutic and scientific professionals will be on-hand to support the participants, along with a nutritionist who will plan their meals.
ESA team leader for research Jennifer Ngo-Anh said: “To make these missions possible, various risks to astronaut health must be minimised.
“This study allows us to address the issue of muscular atrophy caused by weightlessness, but also other stressors such as cosmic radiation, isolation and spatial restrictions.”