In nature, various species can physically make themselves more resilient toward such stresses in nature´s challenging conditions, from the seasonal low temperatures and the lack of food, or the geographic heat and the lack of water. This adaptation is called torpor and it is extremely attractive to be induced in a controlled manner, also in so-called non-hibernators as we humans are, because of its potentially wide use in medicine or for humans on a long-duration human space missions to Mars and beyond. The reduction of an astronauts´ metabolism by torpor would become a key advancement and a game changer for human space exploration since water and food intake could be reduced by up to 75%, thus reducing the spacecraft required payload.
The aim of this Topical Team is to review the current state-of-the-art in the hibernation and torpor line of research and to provide recommendations to ESA on this topic and the future line of research.
Publications:
European space agency's hibernation (torpor) strategy for deep space missions: Linking biology to engineering
Long-duration space missions to Mars will impose extreme stresses of physical and psychological nature on the crew, as well as significant logistical and technical challenges for life support and transportation. Main challenges include optimising overall mass and maintaining crew physical and mental health. These key scopes have been taken up as the baseline for a study by the European Space Agency (ESA) using its Concurrent Design Facility (CDF). It focussed on the biology of hibernation in reducing metabolism and hence stress, and its links to the infrastructure and life support. We concluded that torpor of crew members can reduce the payload with respect to oxygen, food and water but will require monitoring and artificial intelligence (AI) assisted monitoring of the crew. These studies additionally offer new potential applications for patient care on Earth. Keywords: Space flight, concurrent design facility, metabolic reduction.
Authors: Alexander Choukér, Thu Jennifer Ngo-Anh, Robin Biesbroek, Gerhard Heldmaier, Marc Heppener, Jürgen Bereiter-Hahn
Hibernating astronauts-science or fiction?
For long-duration manned space missions to Mars and beyond, reduction of astronaut metabolism by torpor, the metabolic state during hibernation of animals, would be a game changer: Water and food intake could be reduced by up to 75% and thus reducing payload of the spacecraft. Metabolic rate reduction in natural torpor is linked to profound changes in biochemical processes, i.e., shift from glycolysis to lipolysis and ketone utilization, intensive but reversible alterations in organs like the brain and kidney, and in heart rate control via Ca2+. This state would prevent degenerative processes due to organ disuse and increase resistance against radiation defects. Neuro-endocrine factors have been identified as main targets to induce torpor although the exact mechanisms are not known yet. The widespread occurrence of torpor in mammals and examples of human hypometabolic states support the idea of human torpor and its beneficial applications in medicine and space exploration.
Authors: A Choukèr, J. Bereiter-Hahn, D Singer, G Heldmaier