What Is Space Radiation and Why Is It Important?

What is space radiation? And why is it so important that we know about it? These are questions you might have asked yourself after going through the profile of our recently launched crowdfunding campaign on SpaceStarters. We try to briefly answer these questions in this post and also point you to some great resources freely available on the web that can help you to get a deeper understanding of the topic!

Radiation in space is very different from its terrestrial counterpart. The majority of it is created in the explosions of massive stars, called supernovae. The various ionized elements bred in the star’s inner cores are accelerated by the shock of the explosions to almost the speed of light and hurled across the galaxy. Due to their large energy (speed), these particles can hardly be stopped by currently available shielding materials. Only very large material volumes or magnetic fields, like Earth’s atmosphere and magnetosphere, can provide some shielding.

A second source of radiation is our Sun: During periods of intense solar activity, large numbers of particles are released from the Sun’s outermost layer and accelerated towards Earth. We sometimes get the opportunity to see them when they hit our planet’s atmosphere and create aurorae. Even though still quite energetic, these solar particles are slower than the cosmic radiation created in the explosion of stars and can be shielded against with current materials.

A third source are particles trapped in the Earth’s magnetic field. This low-energy radiation forms two donut-shaped rings around the planet, but poses no threat unless astronauts travel through the rings unprotected.

Radiation affects our bodies in multiple ways. The low exposures we receive in our daily lives (thanks to the shielding of Earth’s atmosphere) pose no threat to us because the human organism has evolved to counteract its effects. The radiation intensity in space, however, is orders of magnitude higher than on Earth. Such high exposures can damage our cells’ DNA, which can ultimately lead to the growth of cancerous tissue. The actual dose of radiation astronauts receive during their missions is therefore constantly recorded to ensure that the risk of cancer growth does not exceed a certain threshold.

If high doses are received during short periods of times, for example during solar flares, acute effects can severely affect human bodies almost immediately. These effects range from cognitive impairment and memory loss all the way to death at very large exposures. Due to this large range of possible medical complications, it is imperative that we monitor the radiation environment astronauts are exposed to at all times. Our 3D-DOS experiment will help to do just that.

You can learn more about the radiation environment in space in this podcast and this very nice ebook, both published by NASA.


Picture credit: NASA