The solar storm that affected Earth between Friday (20) and Sunday (22) with intensity considered strong caught the attention of space agencies and raised an alert for astronauts in orbit, who are more vulnerable to this type of phenomenon.
When we are on Earth, we are protected by an invisible “blanket”, which is the magnetosphere and atmosphere, which filter most of this radiation. Even astronauts on the International Space Station (ISS) still have some protection because they are in low orbit.
However, when traveling into what is considered to be deeper space, the objective of the Artemis II missions this year, this shield disappears, leaving astronauts exposed.
This ionizing radiation can pass through living tissue, depositing energy that causes structural damage to DNA and alters several cellular processes.
Scientists classify the danger into three main sources:
- Galactic cosmic rays (GCR): These particles travel at nearly the speed of light, coming from outside our solar system. They are the most difficult to block;
- Solar Particle Events (SPE): they are sudden eruptions from the Sun that can flood a ship with radiation in a matter of minutes;
- Van Allen Belts: zones of intense radiation that surround the Earth and need to be crossed quickly.
Human body under attack
According to NASA, prolonged exposure to these particles does not cause real biological changes in the astronauts’ bodies. The impact is compared to a , which increases the risk of developing cancer by up to 5% and can affect the central nervous system, impairing memory, motor coordination and the ability to make decisions during the mission.
According to the space agency, the crew’s health may also be affected, as the heart and arteries suffer stress due to this exposure, increasing the risk of heart disease and hardening of vessels such as the aorta.
Another problem that can affect astronauts is Acute Radiation Syndrome. In cases of extreme solar flares without adequate shelter, astronauts can experience nausea, fatigue and immune system failure.
“Exposure to space radiation can also increase the risk of other degenerative diseases that affect multiple tissues, such as the heart, blood vessels and eyes. Additionally, exposure to space radiation can affect the central nervous system, causing cognitive or performance impairment during missions, and can increase the risk of astronauts developing degenerative diseases later,” says NASA, on its website.
To get an idea of how much this radiation affects astronauts, NASA recently unified the limits at 600 mSv (millisieverts) for their entire career, regardless of age or gender, allowing more women to participate in long-duration missions. For comparison, a person on Earth receives about 3 mSv per year.
Space engineering is looking for alternatives to reduce risks. The Orion spacecraft, which will take humans to the Moon, for example, has areas with reinforced shielding that serve as “panic rooms” during solar storms.
In addition, NASA is focused on advancing “personalized medicine” by seeking to develop strategies that protect astronauts’ health and ensure safe human space flights. Through the AVATAR project, they are using “human tissue chips” to predict how each specific astronaut’s body will react to radioactive bombardment before he even leaves the launch pad.
