MAPHEUS 12 during launch in Kiruna. Credits: DLR
On 21 October 2022 at 09:25, the MAPHEUS 12 research rocket of the German Aerospace Center (Deutsches Zentrums für Luft- und Raumfahrt; DLR) took off from the Esrange Space Center near Kiruna in northern Sweden. It reached an altitude of 260 kilometres before descending back to Earth on a parachute. On board for the first time were nerve cells. The goal is to understand how their electrical signals deviate in microgravity. The research team also investigated how the polarity of cells behaves under microgravity in connection with the development of cancer. The flight also served as a test run under space conditions for new types of solar cells as well as for an encryption technology that will protect the sensitive data of life support systems and space vehicles in the future. It also marked the first time that a reusable ignition unit was used in the upper stage.
"With MAPHEUS 12, we have transported an extremely diverse package of experiments into the microgravity of near space for approximately six minutes and recovered it safely," says the mission's scientific project manager, Thomas Voigtmann from the DLR Institute of Materials Physics in Space. "We are happy to have the sensitive nerve cells, marine organisms and materials science experiments back on Earth in good condition after a perfect flight." Following its 15-minute flight, the payload landed gently by parachute approximately 70 kilometres from the launch site in the tundra of northern Sweden. A recovery team then flew to the landing site and transported the payload hanging from the helicopter back to the launch base, where the team immediately began securing the collected data.
Upgrades to research rocket and ground station
The rocket, which is 11.5 metres long and weighs more than 1.6 tonnes, was the twelfth to be successfully launched from the Mobile Rocket Base (MORABA) DLR's Space Operations and Astronaut Training facilityof as part of the MAPHEUS series of experiments. "This flight was the first time that the two-stage rocket had the new service module on board, which offers 10 times faster communication with the ground station and more precise attitude information and features completely redesigned electronics, mechanics and software," explains MORABA project manager Alexander Kallenbach.
Neural networks premiere in microgravity
The neurons on board MAPHEUS 12 also experienced their first flight. During the short flight, they were examined directly at the electrophysiological level. The neural network of the Multi-Electrode Array (MEA) experiment consists of cultivated primary neurons distributed over two chips. These find ideal living conditions in a vacuum-tight chamber at 37 degrees Celsius. "During the flight, we were able to record the action potentials of individual neuronal cells as well as the activity of the entire network," reports Christian Liemersdorf from the DLR Institute of Aerospace Medicine. Action potentials are the transduced signals between neurons in the brain and central nervous system. Microgravity conditions are thought to influence the neural connections in the brain. "Presumably, this is a major reason why astronauts often suffer from certain cognitive impairments during their stay in space," Liemersdorf adds. "We are now evaluating the collected data in detail to understand these possible correlations more precisely." Because of the sensitivity of the neurons, it has so far not been possible to carry out experiments with them on the International Space Station ISS.
The entire press release with all images can be found in the DLR portal