Out of This World in 40 Winks

Humans travelling to distant planets in a hibernation-like state may sound like a Sci-Fi movie trope, but recent breakthroughs suggest that human hibernation may be more science than fction.

Experts from around the world have discovered that torpor, a state of suppressed metabolism that occurs during hibernation, can be synthetically induced in humans through the use of certain drugs. This state of induced torpor already has biomedical applications as explained by Oxford University’s Prof. Vlad Vyazovskiy, ‘controlled hypothermia and metabolism are already widely used in clinical practice, such as during cardiac surgery and to protect tissues from damage when blood fow is reduced, such as after a stroke.’ Prof. Vyazovskiy is one of a number of scientists enlisted by the European Space Agency to take part in an international collaborative project, investigating the protective efects of torpor and whether torpor can be used to facilitate long-distance space travel.

Until now, spacefight has been limited by the serious health efects associated with long-term exposure to the hostile environment of space. For example, prolonged weightlessness due to anti-gravity may sound like fun but it also leads to muscle wasting and bone deterioration. In addition, the amount of ionising radiation in space is ten times of that on Earth; consequently, exposure for long periods would result in tissue damage and increased risk of cancer. Moreover, space travel increases the risk of blood clots and subsequent cell death due to lack of oxygen. It is not surprising, therefore, that humans have not managed to venture further than the Moon. F ortunately, hibernating species are protected from these adverse efects. During torpor, suppressed metabolism prevents cell death, tissue damage, and bone deterioration. Furthermore, the cell cycle, the process by which a cell duplicates its DNA and divides in two, is inhibited, which has been shown to limit the damaging efects of radiation. Heart rate and oxygen consumption are also reduced, decreasing the likelihood of blood clots and increasing the body’s ability to withstand low oxygen levels. It is hoped that ‘synthetic torpor could protect astronauts from space-related health hazards’ explained Dr. Matthew Regan, a hibernation researcher from the University of Wisconsin.

Further research is being conducted to determine the long-term health efects of torpor and whether this state can be maintained for the long periods of time required for space travel. For example, recent studies have reported that torpor can be induced in humans for up to 14 days without complications. Although this is a step in the right direction, humans would need to hibernate for up to 140 days just to travel to Mars, demonstrating that more research is required before torpor becomes a feasible solution to long-distance space travel. Despite this work being in its early stages, researchers are optimistic about the utility of torpor, ‘it’s a great research area, and we think this technology will really be enabling for fnally getting us out of low earth orbit’ said Dr. John Bradford, an aerospace engineer and the President of SpaceWorks.

Long-distance space travel becoming a reality is essential for future scientifc breakthroughs. It will allow us to explore further than ever before, therefore developing our understanding of the universe and allowing for human civilisations beyond Earth. This may become crucial for the continued survival of our species as summarised by Sci-Fi author Larry Niven ‘The dinosaurs became extinct because they didn’t have a space program’. Sian Wilcox is studying for a PhD in Physiology, Anatomy and Genetics at Balliol College.

Could human hibernation be the answer to longdistance space travel?