What Health Hazards Do Astronauts Face in Deep Space?
There's a famous horror movie tagline: ”In space, no one can hear you scream."
It's not wrong — there might be a lot of things to scream about once you leave the safety of our planet's atmosphere. You probably know all the basics, like no oxygen and frigid temperatures, but what other hazards are astronauts up against once they reach outer space?
One of the coolest things about spending time in space is that there is limited gravity. Unfortunately, this has its downsides.
While you're floating, you're not using your muscles or bones in the same way that you would on Earth. Calcium leaches from your bones and gets excreted through your urine. This causes the bones to weaken and makes astronauts more susceptible to breaks. Muscles lose tone because they're not fighting against Earth's gravity to keep you upright at all times.
Some medications can counter bone loss, and muscle tone can be maintained through regular exercise, but it's nothing like living on Earth.
Recently, during Scott Kelly's one-year stay on the International Space Station, NASA doctors found out that microgravity also affects ocular pressure, causing problems with vision.
Astronauts go through numerous psychological evaluations before they're allowed to head up into orbit. However, nothing can prepare you for being hundreds of miles above your home planet, seeing a sunrise and sunset every 90 minutes, and being surrounded by a freezing vacuum that could end your life if you make one mistake. Occasionally, astronauts snap and have a psychotic episode.
NASA has a plan in place if this happens. It involves strong tranquilizers, duct tape and bungee cords. Mental health is a massive concern because these brave men and women are facing the unknown on a daily basis. NASA is planning to send astronauts to the moon as a prelude to sending them out further into the solar system, so it's vital to have a plan in place if someone has a psychotic break mid-flight.
The further we get from terra firma, the greater the psychological toll. Once we reach Mars, NASA might need a technique that's more high-tech than duct tape.
We all know not to look up at the sun because it can damage the eyes. Imagine how dangerous our home star is if you don't have the Earth's atmosphere protecting you. That's why astronauts on the ISS wear suits with retractable gold visors when they're outside the space station. This visor is a combination of polycarbonate plastic and gold. Gold, in particular, only transmits 60 percent of incoming light, including both the visible and UV spectrum, and transmits almost no infrared rays.
Down on Earth, we're protected from interstellar radiation by our planet's atmosphere and magnetosphere. On the International Space Station, which orbits about 250 kilometers from the ground, astronauts are still protected by the magnetosphere — even though they're outside the planet's atmosphere.
The further away from home we get, the more that protection weakens. Limited areas on the moon are protected by the magnetosphere for short periods every month, and there are some areas on the moon that are magnetic hotspots that generate a mini-magnetosphere. Once you move past the moon, though, you're basically on your own.
Radiation damage in space is similar to what happens on Earth — burns, radiation poisoning and DNA damage. NASA will have to come up with new ways to protect our astronauts if it plans to send them any further than the moon.
We deal with microbes all day long, from the bacteria on your hands to those living on the surfaces of your home or workplace. These aren't contained environments, though — air flows in and out all day long, and you don't have to worry about recycling air and water like astronauts do in space.
Confined environments — like the Gateway Station that NASA is planning to place in orbit around the moon — create a unique challenge for astronauts and ground control. The last thing you want is to get a cold when you're in orbit, because microgravity weakens the immune system, making it harder for your body to fight off the bug.
To prevent the astronauts from bringing any Earth-bugs into outer space, each one is put through a series of lab tests and then quarantined for seven days before the launch. This limits their contact with anyone who might be sick, even if they're not showing symptoms. In a fully recycled system like the International Space Station, the flu could spread throughout the crew in a matter of days.
Now we're back to our opener — in space, no one can hear you scream. There is little chance of rescue if something goes wrong on a moon or Mars mission. It takes four to five days to reach the moon, and between six and eight months to reach Mars. A lot can go wrong in that time.
This isn't as much of a problem on the International Space Station because it's so close to home. If something goes wrong, the crew can evacuate to the attached Soyuz capsule, detach and splash down in the Pacific Ocean.
Don't Get Scared
These risks should not discourage any potential astronaut from seeking a career among the stars. While there are risks associated with space travel, NASA has a contingency for every possible problem — and then another backup plan for that. Space travel will never be risk-free, but all our ingenuity is aimed towards making it as safe as possible.