Exploring space is a thrilling endeavor, but it comes with its own set of risks. Two of the most significant risks are radiation and altered gravity. Research has shown that both can have significant negative effects on the body and even on the brain. One of the first changes in the body is the movement of fluids.
On Earth, our muscles work to pump fluids through the body against gravity, and gravity helps bring them back. In space, however, even though astronauts enter a lightweight environment, their muscles continue to function as if they were on Earth. This causes fluids to be pumped and concentrated in the upper body, leading to a swelling of the head that is often seen in astronauts. It can also cause increased pressure at the back of the eye, which can change its shape and may change vision.
Without gravity, there is a loss of muscle mass and bone density. To counteract these changes, astronauts exercise for two hours a day using devices such as treadmills and ARES for endurance exercise. However, these machines take up a lot of space, so NASA is working on a miniaturized version for Orion, where space is a scarce commodity. The vestibular or balance system is also affected by the absence of gravity.
Within this system, in our inner ear, there are small crystals that give us information about our orientation. Without gravity, there is no signal to tell the body which direction it is “up” in. The mismatch between astronaut vision information and vestibular system information often causes a feeling of dizziness or space sickness. In addition to these physical risks, there are also psychological risks associated with space exploration. First-generation space stations had crews that spoke only one language, while second and third generation stations have crews from many cultures who speak many languages.
This can lead to communication difficulties and feelings of isolation. The main objective of this academic activity is to discover how well and for how long people can survive the extreme conditions of space, and how quickly they can readjust to the Earth's environment after returning from space. In the future, the industrialization of space and the exploration of the inner and outer planets will require humans to endure increasingly long periods in space. Science reported that Russia is working on plans to build a nuclear-powered spacecraft to achieve this goal. The observations of astronauts traveling on the space shuttle and the prolonged visits of Russian cosmonauts to the Mir space station indicate that the time spent in 0 g has serious effects on bone and muscle physiology and on the cardiovascular system. Another problem, which has not yet been seriously investigated, besides direct cell damage, is the more general effect of space radiation on the immune system. Estimated probability that the nucleus of a galactic cosmic ray will not pass through the nucleus of a blood-forming organ, depending on armor and duration in free space. Therefore, the International Space Station (ISS) will play an enormously important role in assessing human health hazards in space and in developing possible countermeasures.
However, the scarcity of funding means that there are not enough large space vehicles, such as space shuttles, available to transport crew, equipment and supplies and to serve as rescue vehicles in the event of a serious accident on the ISS. Finally, space is a relentless environment that does not tolerate human error or technical failure. The results could influence long-term space flights, including a mission to Mars. The enormous advances in rocket and spacecraft technology over the past 50 years have made it possible to send humans into orbit close to Earth and Moon.
