As the closest planet to earth, the moon has rightly become a key target for human exploration, and in the past, humans have launched a large number of probes to the moon, although not all human probes to the moon are always successful, for example, in 2019, a lunar exploration mission ended in failure.

A failed lunar exploration that left a very viable creature on the moon

The mission, from an organisation called the arch mission foundation, was planned to send a probe called genesis to the moon, which would have landed on the surface of the moon in the northern part of the sea of tranquillity. The mission is scheduled to land in the northern part of the "Sea of tranquillity" On the surface of the moon.

On 21 february 2019, genesis was successfully launched and entered orbit around the moon on 4 april, but during preparations for landing on the lunar surface on 12 april, genesis' main engine unexpectedly failed, causing the probe to fall into uncontrolled orbit. This caused the probe to crash on the lunar surface in an uncontrolled manner.

(before and after view of the genesis crash area)

Among the payload of genesis was a special device called the lunar library, in addition to the usual science equipment (magnetometers, laser reflector arrays, etc.).

The device is similar in appearance to a cd-rom and contains around 30 million pages of data related to human civilisation. The moon library also carries thousands of water bears, some of which are sealed in special epoxy resin and some of which are distributed on the surface of the library.

Water bears are the common name for retarded creatures that are so small, usually no more than a millimetre long, that their presence is usually unnoticeable.

This is a tiny creature, but one that is extremely resilient. In simple terms, it can survive in extreme environments such as high temperature, high pressure, high salinity, high radiation, low temperature, low pressure, lack of oxygen, lack of water and so on.

To study how hardy they are, some of them were even taken into space and exposed to the vacuum of outer space for up to 10 days, and the results showed that around 68% of them survived. This is why they are often referred to as the hardiest creatures on earth.

What is clear is that despite this being a failed mission to the moon, these water bears were sent to the moon by humans and have remained there ever since.

Are the water bears that were sent to the moon in 2019 okay now?

The last telemetry data from genesis before it crashed showed that it hit the moon at a speed of about 139 m/s (about 500 km/h) and that, relatively speaking, the water bears were able to withstand an impact of about 900 metres per second, on top of which, with the cushioning effect of the epoxy resin, the water bears were able to withstand the impact. "The genesis team's preliminary assumptions are that at least some of these water bears would have survived the impact.

This speculation has undoubtedly generated much debate, with some describing the failed mission as "A small step for this group, but a giant step for the entire population", and the imaginative even going so far as to describe how "Water bears have since thrived on the moon, and that in a few years they will evolve into intelligent beings and, in a few years' time, they will be able to survive. They will evolve into intelligent creatures and return to earth".

However, from a biological point of view, even if some of the water bears survive the impact, their future does not look good. Although the water bears are extremely resilient, they are not as tough as many people think and are not able to survive and reproduce in extreme environments, but can only sustain themselves minimally through a state known as 'cryptobiology'.

In simple terms, cryptobiology can be understood as a state of pseudo-death, in which the water content and metabolic level of the water bears' bodies are reduced to a very low level, thus greatly enhancing their ability to adapt to the environment and helping them to survive periods of harshness. When the environment becomes suitable for survival, they may return to their normal state.

In fact, the water bears on board genesis were actually put into a "Cryptic" State beforehand, but even so, it is difficult for them to survive for long on the lunar surface, where the temperature is the greatest threat. The greatest threat to water bears is in fact the temperature of the lunar surface.

The temperature range of a 'cryptobiotic' water bear worm may be as wide as 151 degrees celsius and as low as -272 degrees celsius, but the reality is that if the temperature is too extreme, the worm will not last long.

Studies have shown that water bears in the 'cryptic' state can only last a few minutes at 151°c and -272°c, and a few days at -200°c. When the ambient temperature is heated to 63.1°c, water bears in the 'cryptic' state can only last a few days. When the ambient temperature is heated to 63.1 degrees celsius, the bears die at a rate of 50% per day, and when the temperature rises to 82.7 degrees celsius, they die at a rate of 50% per hour.

Without the protection of the atmosphere, the moon's surface temperature can reach 127 degrees celsius in direct sunlight during the day and -183 degrees celsius at night, a temperature difference of 310 degrees celsius. Even the 'cryptic' water bears cannot survive for long in this harsh environment.

In addition to the temperature, the lack of oxygen, water and high radiation levels on the lunar surface would also be a severe test for water bears, so it is reasonable to assume that all the water bears that were sent to the moon by humans are probably dead by now.

However, some researchers have suggested that, if they are lucky enough, some of the water bears may have penetrated below the surface of the moon during impact, where they could have avoided the harsh conditions on the surface, and in addition, they may have gained access to some water molecules to maintain their 'cryptobiotic' state.

In other words, the best case scenario is that a few of the 'lucky' ones sent to the moon by humans will now be able to maintain a minimal level of life, and it is unlikely that they will be able to thrive on the moon in the future.