To Protect Artemis II Astronauts, NASA Experts Keep Eyes on Sun

Space weather refers to the changing conditions driven by solar wind and eruptions from the Sun. Solar flares are the most powerful eruptions in the solar system, the strongest unleashing more energy than a billion hydrogen bombs. Coronal mass ejections are giant clouds of solar particles hundreds of times the size of Earth that burst from the Sun.

As four astronauts travel around the Moon on NASA's Artemis II mission, they will venture beyond Earth's protective magnetic field. The crew's spacecraft, Orion, will carry and protect them as they journey into deep space and serves as the main protection against the Sun's intense power. During their 10-day flight, NASA and the National Oceanic and Atmospheric Administration (NOAA) will monitor the Sun around the clock and translate space weather conditions into real-time decisions to protect the astronauts.

While both flares and coronal mass ejections can affect technology, the primary concern for astronauts is the solar particle events they can trigger, accelerating some particles to near light speed. If a significant solar particle event occurs near the Artemis II crew, it could raise radiation levels inside the spacecraft. Too high a total lifetime exposure can contribute to increased risks of developing cancer or health disorders that could impair cognition and performance.