Partial G Health Experiment

The mission: research the long term impact of partial gravity on human health.

• What is the impact of partial gravity on human health?
• How much gravity does a human body need to stay healthy?
• What kinds of exercise are needed to keep the human body healthy at partial gravity?
• How much exercise is needed to keep the human body healthy at partial gravity?
• Specifically: what is the health impact of Moon and Mars gravity?

Introduction

The impact of zero gravity on human health has been studied for decades on Russian and US space stations. We know the human body needs gravity to stay healthy, but nobody knows how much gravity is needed. We need research on the health impact of long term living in partial gravity environments, especially the 0.15G on the Moon and 0.4G on Mars.

One way to test the long term impact of lower gravity on the human body would be to set up stations on the Moon and Mars and have people live there for a long time. However, this is very expensive and could be dangerous - sending people to another planetary body without the right exercise equipment could seriously impact their health.

Testing the impact of partial gravity on human health in low earth orbit has several advantages:

• Astronauts could be brought back to earth quickly if health problems come up.
• The gravity on a space station can be adjusted, so various levels of gravity can be tested in one laboratory.
• It may be possible to assemble the space station from available components and launch it with "commodity" launchers.

The impact of the last item cannot be underestimated. If an experiment like this is too expensive, it will not be done. However, if it can be designed "on the cheap", it may be possible to get the funding required to carry out the experiment. Using off the shelf components as much as possible could greatly reduce development and launch costs.

Concept

Initial back-of-the-envelope idea:

• Modify a large Bigelow inflatable space station so it can be rotated to simulate partial gravity.
• Launch the equipment and crew on SpaceX rockets. Chances are those will be ready before this experiment has been fully planned.

By using off the shelf components, the budget for infrastructure design can be minimalized. Getting maximum science return per dollar is the only thing that can make this kind of experiment feasible!

Community involvement

Figuring out all the details involved in a partial gravity health experiment is a lot of work. If you have the time and/or knowledge to "fill in the blanks" in our outline, feel free to do so. If you want to discuss the experiment feel free to join us on irc.freenode.net in #space.

Experiments

The Partial G Experiments will be focussed on the impact of partial gravity on human health.

Maybe microgravity experiments can be done near the axis of rotation. However, those are not a priority and should probably not be done except as a fundraiser.

Space Station

In order to simulate partial gravity, the space station will need to rotate. To make that happen, either the space station needs to be of a sufficiently large diameter or consist of several components mounted in a "dumbell" arrangement.

The current idea is to modify a Bigelow inflatable space station by assembling a floor from smaller rigid components inside the inflatable walls. See Partial G Space Station.

Launches

To save costs, only off the shelf launch vehicles will be used: Partial G Launch Vehicles.

Cost estimates

Unlike zero gravity workshops, which are used for all kinds of experiments, the partial gravity research laboratory is useful only for a smaller set of experiments. To put it bluntly, costs will need to be lower.

In order to ensure that constraint, the Partial G Cost Estimates page will be used to track cost estimates during every phase of planning the experiment.