September 12, 2023 | The 41st DLR parabolic flight campaign takes off from Bordeaux

Flight of German-Japanese friendship

  • The 41st DLR Parabolic Flight Campaign of the German Space Agency at DLR is taking place in Bordeaux from 4 to 15 September 2023.
  • A German-Japanese experiment is on board.
  • This time, 11 experiments from the fields of biology and life sciences, biotechnology as well as fundamental physics, materials science and technology are on board.
  • Focus: Spaceflight, research in microgravity

On 12 September 2023, it was time again – the Airbus A310 operated by Novespace took off from Bordeaux-Mérignac Airport at 09:00 CEST to carry researchers and their experiments into microgravity. This was the first of three missions in the 41st parabolic flight campaign organised by the German Space Agency at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR). The campaign will run from 4 to 15 September 2023. On board are 11 experiments – five from the fields of biology and life sciences, one from biotechnology as well as three from fundamental physics, one from materials science and one from technology.

Also on board – a German-Japanese experiment

"This time, a very special experiment is also on board for the 41st campaign. We have a team from Japan with us that is investigating planet formation together with a German team. We are very pleased that our flights in microgravity are becoming more and more international and that teams from distant countries are also taking the opportunity to bring their experiments into microgravity with us, in cooperation with German scientists," said Katrin Stang, Parabolic Flight Programme Manager at the German Space Agency at DLR, looking forward to the upcoming flight days. The aforementioned German-Japanese experiment 'ice-DUST' is one of three new experiments and investigates how ice nanoparticles and water molecules clump together to form ever larger dust particles, the formation of which ultimately contributes to our understanding of planet formation. The 'DALERA' experiment, which is also new, is testing a novel 3D bioprinting method in microgravity for both medical and non-medical applications. The 'Tears in Heaven' experiment is investigating whether measurements of blinking and tear film dynamics allow conclusions to be drawn about the condition of the ocular surface in microgravity.

Reserve astronauts get a taste of experimenting in microgravity

Two experiments also have a prominent team member on this campaign. German ESA reserve astronaut Amelie Schoenenwald will be assisting scientists in the 'TRANSEUGRA' experiment to learn more about the single-celled organism Euglena gracilis. The other German ESA reserve astronaut, Nicola Winter, will be working with the 'SCARLETT' experiment, helping to study the slipping of a hillside, mountain or crater wall on a simulated martian surface. In this way, the two can experiment in free fall for a possible mission on the International Space Station ISS and get a preview of working in microgravity.

Video: Parabolic flights in the world's largest parabolic aircraft – research in microgravity
Since 1999, the German Space Agency at DLR has been organising regular parabolic flights for biological, human physiological, physical, technological and materials science research. The research aircraft, the A310 ZERO-G of the French company NoveSpace is used once or twice a year for scientific campaigns conducted by DLR, the European Space Agency and the French space agency CNES. A DLR parabolic flight campaign usually consists of three flight days with approximately four flight hours, during each of which 31 parabolas are flown. During each parabola, microgravity prevails for about 22 seconds. In total, a flight campaign provides about 35 minutes of microgravity –alternating between normal and almost double gravitational acceleration – which researchers can use for their experiments. Up to 40 scientists can take part in each flight, with between 10 and 13 experiments on board.

ice-DUST – How planets are formed from ice and dust

In the depths of space, water ice forms on the surfaces of cosmic dust particles in cold molecular clouds. If other molecules are also formed, these are primarily deposited on the icy surfaces. When a protoplanetary disc and eventually a new planetary system forms from this molecular cloud, the temperature increases before the protoplanetary disc cools down again. This causes the ice to sublime, before the resulting water molecules redeposit on the dust particles. Sublimation takes place in thermal equilibrium, while condensation is a non-equilibrium process and includes nucleation. Therefore, theoretical predictions about the formation of ice particles in young planetary systems are difficult, and the temperature and density conditions for sublimated ice to re-cover the dust are not clear. The German-Japanese research team from Technische Universität (TU) Braunschweig wants to determine the most important physical parameters, such as surface free energy and adhesion probability of ice nanoparticles for the expected particle sizes in the nanometre range, under realistic temperature and pressure conditions during a parabolic flight. This will be achieved by nucleation experiments on mineral dust in order to learn more about the formation of planets.

DALERA – 3D bioprinting in microgravity

If humans want to explore the Moon, and later Mars, the crews must be provided with medical care and at the same time the operation of life-support systems must be improved. 3D bioprinting – that is, 3D printing involving living cells – shows great potential for both requirements. For example, 'customised' tissues for humans could be produced autonomously to treat crew injuries such as skin wounds in space, independent of Earth. In addition, this extremely versatile technology can also be used for non-medical applications such as the creation of life-support systems, the production of food or for drug synthesis – for example, through the bio-printing of microalgae or plant cells. The knowledge gained from this parabolic flight mission will help to better understand the influence of microgravity on the 3D bioprinting process. The team from TU Braunschweig / Carl Gustav Carus University Hospital Dresden wants to use DALERA to prepare experiments for use on board the ISS, where a 3D bioprinter is to be installed by the European Space Agency (ESA) for research purposes by the end of 2026.

'Tears in Heaven' – how tears flow in microgravity

Astronauts are exposed to unique environmental conditions in microgravity that can affect their daily work on board the space station. For example, problems with the ocular surface occur frequently, but have not yet been adequately investigated or treated. Symptoms of dry eye include eye irritation, eyestrain, foreign body sensation and blurred vision. These symptoms are commonly reported by astronauts, with over 30 percent of ISS crewmembers reporting irritation and foreign body sensation. Initial analyses based on photographs of astronauts revealed that eyebrow height, for example, increases significantly in microgravity. This could have a negative effect on the blinking process. At the same time, a healthy tear film – and thus clear vision – is one of the prerequisites for functional eyes and at the same time the basis for successful work inside and, above all, outside the ISS. The research work conducted by the Saarland University team on Earth has shown that measurements of blinking and tear film dynamics allow conclusions to be drawn about the condition of the ocular surface. In this first phase of the 'Tears in Heaven' project, they want to test whether and how tear films and blinking can be studied in microgravity and double gravity.

TRANSEUGRA – perception of light and gravity in unicellular organisms

Single-celled organisms – such as the freshwater alga Euglena gracilis – react sensitively to changes in their environment. "Since biotechnologically and medically important substances with a broad range of applications can be obtained from this alga and thus plays an increasingly important role in biotechnology, we want to find out more about its orientation behaviour with regard to light and gravity. This is the only way to further improve the mass production of this alga in the future. As I was already interested in astrobiology during my studies, I am now particularly looking forward to being able to try my hand at microgravity myself. That is only possible during a parabolic flight or on the ISS," explains Amelie Schoenenwald, who is supporting the University of Erlangen in its experiments. For example, the cells swim towards weak light sources and away from strong light sources. In addition, they exhibit a tumbling behaviour when there is a sudden change in light intensity. The cells are also able to perceive gravity and adjust their swimming behaviour accordingly. Without light, the cells swim upwards against gravity. Since the signalling pathways of light and gravity perception overlap, one of the possible interactions will be investigated in the flight experiments. Only in microgravity can the perception of light be investigated separately from that of acceleration, as the cells are no longer affected by Earth's gravitation.

SCARLETT – when martian slopes start to slip during parabolic flight

Mars has an extremely tenuous atmosphere. While the pressure on Earth at sea level is approximately 1000 hectopascals, it is on average just six hectopascals at the martian surface. This low pressure has consequences. Gas moves from cold to warm locations in porous soils, a process referred to as thermal creep. In the Solar System, this phenomenon is only found on Mars. "Even during my studies, I was interested in the laws governing the planets in the Solar System. When I was asked if I wanted to participate in such an experiment during a parabolic flight, I was immediately interested because, in this way I can prepare myself very well for a later assignment in space," says Nicola Winter, who is supporting researchers from the University of Duisburg-Essen. SCARLETT is investigating whether and how the slope of a hillside, mountain or crater wall will slip above a certain angle of inclination due to thermal creep. In martian craters, too, or on martian hillsides, these slopes become unstable above a certain angle and slip down. However, the angles of these slopes are much shallower than expected. The researchers want to find out under what conditions and at what angle the slopes begin to slip.


Martin Fleischmann

German Aerospace Center (DLR)
German Space Agency at DLR
Communications & Media Relations
Königswinterer Straße 522-524, 53227 Bonn
Tel: +49 228 447-120

Katrin Stang

German Aerospace Center (DLR)
German Space Agency at DLR
Research and Exploration
Königswinterer Straße 522-524, 53227 Bonn