Australian duckweed launches into space

The MAPHEUS 15 sounding rocket was successfully launched at 7:38am (UTC) on Monday, 11 November, and contained 21 scientific experiments from organisations all around the world.

The University of Adelaide’s MiniWeed experiment, conducted in collaboration with DLR and Melbourne’s La Trobe University, will test how altered gravity affects duckweed – a plant identified as a potential food source for astronauts.

“We are excited to reach this major milestone of launching a sample of Wolffia australiana in a sounding rocket experiment,” says the University of Adelaide’s Associate Professor Jenny Mortimer, Chief Investigator at Plants for Space (P4S).

“Our P4S collaborator at the DLR, Dr Jens Hauslage, has designed an experimental system that will chemically pause the plant’s development at two points in the rocket’s journey: the end of the hypergravity phase, and the end of the microgravity experiment.

“Once we retrieve the samples, we will look at the effects of the altered gravity on the plant biology, in particular, gene expression.

“These experiments will also help us understand how well our gravity-simulation systems in the lab mimic these real-world effects, particularly on an aquatic plant like duckweed.

“They will also help us prepare benchmarking data for experiments we’re conducting as part of NASA’s LEAF program, during which we will grow plants, including Wolffia, on the lunar surface, and return them to Earth.”

Following the launch, Associate Professor Mortimer will work with La Trobe’s Professor Mathew G. Lewsey to analyse the biological and molecular effects on the duckweed, which will help the researchers prepare for future launches to deep space.

Another University of Adelaide experiment, titled StarMed, will test the reliably of medicines created in space.

“If astronauts get sick on the Moon or Mars, they need medicines manufactured at the site of consumption that are stable under microgravity and cosmic rays, as drugs decompose faster in space,” says the University of Adelaide’s Professor Volker Hessel, Program Lead at the ARC Centre of Excellence Plants for Space.

“The StarMed experiment will show us how the stability of liquid medicinal formulations developed for auto-injection by astronauts under changed gravitational conditions, and we will find out how the controlled release of the encapsulated drug melatonin behaves during the space flight.

“Dr Hauslage will also perform vibration tests on ground with the samples in DLR's NyMEx Experimental Module, in order to have a standardised ecosystem benchmark to the rocket's and other vibrations.”

This week’s MAPHEUS 15 launch was the 600^th to fly over the icy landscape of Swedish Lapland, and it achieved a height of 309km. The experiments spent seven minutes in weightlessness, as opposed to the six minutes of earlier flights.

There were also more experiments included this time than on previous launches.

“We were able to accommodate many smaller experiments, which fit into 10-centimetre cubes, due to two specially built rocket segments, called MOSAIC. This reduces development times and costs for each experiment and increases how many we can have on board,” says Professor Thomas Voigtmann, MAPHEUS project manager at the DLR Institute of Materials Physics in Space.

MAPHEUS, which stands for “material physics experiments under weightlessness”, has conducted flights with sounding rockets since 2009.

P4S officially launched in 2024, and the MAPHEUS experiment is the first time the Centre has sent plants into space.