"Dream - Missions to outer space always attract attention, especially during the moments when astronauts return to Earth. It is important to note that astronauts who have just returned from space are always assisted to walk upon landing. This raises the question, why do astronauts have difficulty standing upright after returning from space? According to Thomas Djamaluddin, an expert in astronomy and astrophysics from the National Research and Innovation Agency (BRIN), there are several factors that cause astronauts to experience these difficulties after undergoing long-duration missions in space."

One of the main causes is muscle weakness. In the early missions, such as the Apollo missions, astronauts often experienced this problem because there was no adequate training to maintain their muscle strength in microgravity conditions. In weightless conditions, the muscles do not receive enough stimulation, resulting in a decrease in muscle strength.

"Djamaluddin explained that early generation astronauts were often assisted when returning from space because they lost a lot of muscle strength. However, along with the development of technology and understanding of the effects of microgravity, astronauts now perform regular exercise during their missions. They use special equipment to train their muscles, so when they return to Earth, they do not experience significant muscle strength loss. 'They still have to do exercises, so these legs need to be moved and there is equipment to keep the muscles active,' he added."

"Besides muscle weakness, another issue faced by astronauts is related to blood circulation. In a microgravity environment, the heart must adapt to regulate blood pressure in a different way. Gravity plays an important role in blood circulation. Without the force of gravity, blood circulation can be disrupted."

"Nevertheless, Djamaluddin stated that there are currently techniques being developed to maintain the astronaut's blood circulation to remain normal, so that when they return to Earth, the impact on blood circulation can be minimized. "But I think there are already techniques developed so that blood circulation can be kept normal. So when they return to Earth, there won't be too many changes in aspects of blood circulation," explained the astronomy and astrophysics expert from the National Research and Innovation Agency (BRIN)."

Another cause faced by astronauts is bone loss. Research conducted at the International Space Station (ISS) shows that the bone density of astronauts experiences a significant decrease. This is due to the lack of load that bones receive in microgravity conditions. When astronauts return to Earth, their bones may not be as strong as before. As a result, they experience difficulties when walking.

"Becoming an astronaut is indeed not an easy task. They must face various health risks due to the microgravity conditions experienced during space missions. Muscle weakness, blood circulation problems, and bone loss are some of the challenges that must be faced after returning to Earth. Fortunately, with ongoing research and advancing technology, astronauts can now make better preparations to minimize the negative impacts of their space missions."