Mission Europa

Ingredients for Life

Europa appears to contain all of the essential ingredients needed to support life as we know it here on planet Earth. By surveying our Solar System, as well as the wider Universe, for signs of these ingredients, scientists can narrow down the search for extraterrestrial life.

1. Water

   Earth is the only planet in our Solar System known to have liquid water on its surface. This is what allows life to thrive here - out of all the millions of different species that call our planet home, all of them need liquid water at some point in their life cycle to survive. So, it makes sense that water is the first thing scientists look for as an essential ingredient for life.

    

   Water on Europa

   Scientists believe that, beneath its icy crust, Europa contains a liquid water ocean with more than twice as much water as all of Earth's oceans combined. The best evidence for this was collected by the Galileo spacecraft, which orbited Jupiter between 1995 and 2003. The spacecraft detected variations in Jupiter's magnetic field in the space around Europa. This suggests that Europa is inducing its own magnetic field, which is likely to be powered by its subsurface ocean.

   Additionally, Europa has the smoothest surface of any body in the Solar System, with a significant lack of craters. It could be that the warmth of an internal ocean shifts the landscape and smooths any craters out.

2. Chemistry

   Life here on Earth is made up of certain chemical 'building blocks'. This includes elements like carbon (which is needed to form organic compounds like fats and proteins), nitrogen (which is needed to make DNA) and phosphorus (which aids in cell growth and repair). These elements make up the majority of living matter on Earth.

    

   Chemistry on Europa

   These elements are also common in the Universe at large. Scientists think it is likely that these chemical elements can be found in Europa. Currently, they may exist within the moon's icy shell, having been incorporated into Europa when it formed millions of years ago. It is also possible that they were delivered by comets and asteroids bombarding the moon's surface.

3. Energy

   Energy is needed to fuel all life processes, from simple movement to growth and reproduction. On Earth, the primary source of that energy comes from the Sun, in the form of solar radiation. The Sun powers photosynthesis in plant life, which provides food for humans to eat as well as oxygen to breathe.
   
   

    

   Energy on Europa

   It's unlikely that any life on Europa would get their energy from the Sun, as the conditions on the surface are too harsh. Europa's surface is bathed in high-energy radiation from Jupiter, which would prevent any life from surviving. The rate of radiation received from Jupiter is enough to kill human life within 24 hours of exposure. Therefore, life would be much likelier to exist within the subsurface ocean, out of reach of sunlight.

   Instead, energy is generated through tidal forces under Jupiter's strong gravity. As the moon orbits Jupiter, it is squashed and stretched, producing heat and potential volcanic activity.