Hey Lykkers! Ever wondered what happens to astronauts when they spend months in space? The body is pretty incredible, but the lack of gravity, radiation, and confinement in a spacecraft take a toll. Let’s dive into some of the mind-blowing changes that happen to astronauts during long missions in space.

The Longest Spaceflight – 437 Days in Space

The current world record for the longest spaceflight is a staggering 437 days! That's over a year in space! But even shorter trips can have an unexpected impact on the body.

For instance, astronauts Suni Williams and Butch Wilmore were supposed to be in space for just eight days on a 2024 mission to the International Space Station (ISS).

But due to technical difficulties with their spacecraft, their trip stretched into an unplanned, extended stay. So, what exactly happens when you’re out there for longer than expected?

Muscle and Bone Loss

In space, muscles and bones weaken rapidly. Without gravity pulling on their bodies, astronauts don’t need to use certain muscles as much, leading to muscle atrophy. After just two weeks, astronauts can lose up to 20% of muscle mass! Over months, this number can rise to 30%. Bones are also affected—astronauts can lose up to 2% of bone mass per month! To fight this, astronauts exercise 2.5 hours a day to keep their muscles and bones in shape.

What About Height?

Here’s a fun fact: astronauts actually grow taller in space! Without gravity, their spine stretches out, adding a couple of centimeters to their height. However, this temporary "growth" can cause back pain or slipped discs upon returning to Earth.

The Impact on the Brain

Space affects the brain, too. Astronauts have to adjust to a zero-gravity environment, which impacts how they move and even think. Studies have shown that astronauts may experience cognitive decline for a few months after returning, as their brain needs time to adjust to Earth's gravity. Their balance and spatial awareness can also be affected.

Changes in Vision

Spending time in space can even mess with your vision! The absence of gravity can cause fluid to collect in the upper part of the body, leading to swelling in the eyes. This can decrease vision and sometimes change the shape of the eye. Astronauts have reported blurry vision or difficulty focusing after long missions.

Gut Bacteria on the Space Station

Here’s something you wouldn’t expect: space travel affects the bacteria in our gut. The microbes in our digestive system can change due to differences in diet, exercise, and even exposure to space radiation. Astronauts often experience digestive issues when they return, as their body adapts back to Earth's gravity and environment.

The Challenges of Space Travel

Space travel presents numerous challenges to the human body, from muscle and bone loss to changes in vision, brain function, and even the microbiome. However, scientists are continuously studying these effects to help make long-term space missions, like those to Mars, safer and more manageable for astronauts.

As we continue to explore the cosmos, we’ll learn even more about how space shapes our bodies and minds. Stay curious, Lykkers!