April 12, 1961 Yuri Gagarin became the first person in history to fly into space. After a few decades, the incredible became almost commonplace – the world started talking about space tourism. True, it did not start very smoothly: in 1986, the first space tourist was supposed to be the American teacher Christa McAuliffe, who died 73 seconds after the launch of the Challenger shuttle, and the United States passed a law prohibiting non-professionals from flying into space. But the world was changing, and ways were improving to ensure the safety of passengers.
All this, however, does not mean that humanity has subjugated the cosmos. We still have a lot of tasks ahead of us, for example, plans to colonize Mars. And now scientists do not miss the opportunity to use space for their own purposes. The International Space Station is a laboratory in orbit where unique experiments can be carried out. This could potentially be useful for both astronauts and future inhabitants of Mars, the flight to which, as it turned out, is twice as dangerous as everyone thought. But so far this allows at least to obtain data for scientific, including medical, discoveries.
Mice in space
The state of the liver is negatively affected not only by alcohol and fatty foods but also by space flights. This conclusion was reached in 2011 by researchers from the University of Colorado, who first sent the rodents into space for almost two weeks (more precisely, for thirteen and a half days), and then looked at how their organs changed after this unusual journey. Analysis of the data showed that the main problems were associated with the liver: the animals showed the initial signs of non-alcoholic fatty disease. It is rather difficult to establish the exact reason in such experiments, but scientists have suggested that the flight triggered processes that provoke the development of fibrosis (proliferation of connective tissue).
As for laboratory mice, their travels into space are among the most important for modern science. Experiments on rodents cannot be replicated in humans for ethical reasons – but they help to understand whether the human body can cope with the effects of prolonged powerful cosmic radiation that can cause mutations, for example, leading to malignant tumors. After returning to Earth, they are introduced into the organisms of surrogate mouse mothers and, under traditional conditions, the growth and development of mice are observed.
The abundance of research on topics that at first glance seem unscientific (such as finding the reason why women sniff their partners’ shirts) helps to believe that science is not necessarily boring. This is especially true when scientists team up with gastronomic – or, in this case, alcoholic – enthusiasts. In 2017, Czech brewing company Budweiser announced that it would soon ship barley seeds to the ISS.
Of course, brewers couldn’t do it entirely on their own. They have joined forces with the Center for the Advancement of Space Science, which runs the American laboratory on the ISS, and the private company Space Tango. It is planned to send twenty barley seeds to the space station, which will take part in at least two experiments: the first will study the behavior of seeds in microgravity (that is, gravity within the spacecraft, which is present, although much weaker than on Earth), the second is the growth of barley in zero gravity.
Sex and childbirth on Mars
If we take the talk of colonizing Mars as something real, an extremely important question arises: what to do with reproduction? It is very important to take into account the effect on the germ cells of solar radiation, which is a hundred times stronger in space than on Earth. Another important factor is microgravity, which, as mentioned back in 1988, can accelerate the movement of sperm. However, thirty years ago, researchers were unable to establish whether this affects the fertilization process.
That all changed in 2017 when Japanese scientists sent frozen sperm samples from mice into space that had been stored on the ISS for nine months. When they were returned to the ground, thawed, and then used for fertilization, it turned out that the damage, although there was, was minimal. As a result, nine “space” mice were born at once – completely normal, without abnormalities in the genome or development, which themselves turned out to be capable of fertilization and gave full-fledged offspring.
This experiment made it possible to say that space is quite suitable for fertilization. It’s another matter that mice were born on Earth, and sperm cells were stored on the ISS for not so long – and if these conditions change, genome modification may become more significant. They plan to test this as soon as the opportunity presents itself, the researchers said.