The first space biology article has been published in South Africa, marking an important advancement for African space science – and potentially for the world.
The article, based on a study of young earthworms exposed to various hypergravity conditions for eight days, was authored by researchers at the North-West University (NWU). For earthworms to reach space, they have to withstand hypergravity during launch and decelerations.
While it was expected that earthworms exposed to hypergravity would fare worse than control worms at 1 G (earth gravity), unexpectedly, they all grew at the same rate irrespective of the hypergravity treatments.
Being able to withstand sustained hypergravity suggests that they would also be able to tolerate microgravity and may therefore play roles in space food production and waste recycling on the Moon, Mars, space stations, or on spaceships that experience microgravity.
"This is a proud moment for South African science. It shows that we have the expertise and capability to contribute to important areas of research with global significance,” says research team member Prof Henk Bouwman, a zoologist with expertise in ecotoxicology.
The other team members are Cornel-Mari du Preez, an MSc student specialising in microplastics and Ruwaan Botha, a mechanical engineering graduate with experience in rapid prototyping.
Study could aid future space exploration
Cornel-Mari highlighted the study’s importance: "Understanding how organisms respond to the environment in space is crucial as we look toward future human space exploration."
Insights from this research could support sustainable space travel and protection of biological life beyond Earth, she said, and it lays the groundwork for applications in fields like human health, agriculture, and environmental sustainability in space and on Earth.
She played a key role in studying the effects of hypergravity on small organisms. With a background in marine biology, ecotoxicology and conservation, she was drawn to studying biological responses in dynamic and extreme environments.
Device developed to simulate gravity
Her published work involved using a concentric 3D-printed centrifuge rotor capable of testing organisms under three different gravitational forces: 1.7 G, 2.5 G, and 3.1 G - alongside a 1 G control, allowing for concurrent hypergravity testing that otherwise would have required three separate centrifuges, or three consecutive runs. This novel centrifuge rotor, which she co-developed with Ruwaan, allows researchers to study biological processes under multiple simulated hypergravity treatments, potentially informing sustainable food production and waste recycling in space environments under controlled conditions.
A mechanical engineer, Ruwaan contributed his expertise in design and 3D-printing technology. He co-designed the study’s 3D-printed rotor which can simulate hypergravity conditions and is adaptable for various research applications, including studying small organisms, cell cultures and biochemical reactions over prolonged periods. There is no other such rotor design.
His work on this device reflects his interest in rapid prototyping and computer-aided design (CAD), and his technical contributions have ensured that the research team can explore gravity’s effects on biological systems at multiple intensities. It is not only earthworms that can be tested, but also plants, microorganisms, and other small animals. Outside the scope of space biology, this design might also find use in medical applications, physiology, and biochemistry.
In conclusion, Prof Bouwman emphasised that the study not only adds to space biology knowledge but also underscores Africa's growing role in global scientific conversations: "We’re at the beginning of a new era where the study of space biology is no longer the exclusive domain of a few nations. This article is a step toward Africa’s voice in the global conversation on space biology and science."