Space

Before setting foot on Mars, the NASA space agency plans to send people to the moon in 2024, where it plans to establish a permanent base. At a distance of approx. 385,000 kilometres, our nearest neighbour in space could act as a springboard to Mars. “Inhabitants of the future Moon Village, such as astronauts, will not be able to return to Earth for supplies for a certain period. They will have to produce their own water, food and oxygen on the spot”, explains Natalie Leys, microbiologist at SCK CEN. But how? Will it be possible to sow, plant and harvest crops on the moon?

In order to answer this question, scientists from SCK CEN, the Deutsches Zentrum für Luft- und Raumfahrt and the University of Edinburgh sent bacteria and basaltic rocks into space last year. “Basalt is a volcanic rock, which is also found on the moon”, explains SCK CEN scientist Rob Van Houdt who is coordinating the project. “We were checking whether bacteria attaches itself to this type of lunar rock and whether it develops. Are they able to release the necessary nutritive elements (nutrients) from the lunar rock under the influence of microgravity and space radiation, in order to transform the rock into a more “fertile” soil? We could then use these nutrients as raw materials to produce food. And this would make agriculture possible in space.”

In the autumn, six months after the experimental flight with bacteria, UNamur and SCK CEN sent a cargo of rotifers from the Kennedy Space Center in Florida to the ISS. The rotifers survive in an airless space and are more resistant to high doses of radiation and even dehydration. This is remarkable, as their cell structure resembles that of human beings”, explains Sarah Baatout, radiobiologist at the SCK CEN. By means of this space experiment, the research partners wish to identify the underlying causes. The advantage is that “this information can play a part in developing ways of increasing astronauts’ resistance to radiation during future space voyages.”

The rotifers have been circling the Earth for two weeks, which meant that they were exposed to the effects of space. After a successful flight, the scientists examined the rotifers in terms of reproduction, gene expression and genome structure. According to Boris Hespeels, biologist at UNamur, “genetic expression tells the cells that they are producing proteins. This is necessary, for example, in order to repair damage caused to the DNA. By studying this gene expression in detail, we can see which processes take place in the rotifers and therefore which mechanisms protect against the extreme space environment. We then checked their genomes to determine whether the damaged DNA had been correctly repaired. A badly repaired genome can lead to infertility and anomalies in the progeny even after death.”

UNamur and SCK CEN have also kept rotifers on Earth and treated them in the same way. Karine Van Doninck, biologist at UNamur: “By comparing the status of the rotifers that travelled into space with that of rotifers on Earth, we can study the impact of extreme space conditions on the exposed rotifers. How does their progeny behave, for example? Because they clone themselves and therefore reproduce asexually, they also copy any errors that appear when the DNA is repaired.”

The rotifers were able to repair their DNA without any problems under the influence of cosmic rays. Subsequent research will have to show how they manage to do this. These discoveries pave the way for more extensive space exploration, but this research will also be useful on Earth. Radiobiologist Bjorn Baselet from SCK CEN says that “our results may lead, for example, to measures aimed at a more effective protection for cancer patients or occupational workers who are exposed to the negative effects of radiation during their treatment.”