Water on Europa

 At the end of September, scientists from NASA, using data from the Hubble Space Telescope announced that they had discovered water vapour plumes on Jupiter’s moon, Europa. The plumes extend more than 100 miles into space. The discovery was announced in a hastily arranged press conference amidst excitable rumours that NASA had discovered aliens. No aliens were forthcoming, but the discovery is certainly is good news for planetary scientists looking for extraterrestrial life.

Europa, slightly smaller than earth’s moon, is hypothesised to have a liquid water ocean beneath a thick crust of ice, kept warm by tidal interactions between Europa and Jupiter.

NASA’s hunt for life outside of our planet, has traditionally been focused on Mars, and that work is still ongoing with landers and orbiters observing the planet in ever greater detail. However, moons with liquid oceans beneath the surface such as Enceladus (a moon of Saturn) and now Europa have become the next step in the quest for life.

The only life in the universe that we know of, is life on Earth. All this life is dependent on water. As our knowledge of life on our planet increases, so too does the range of habitats where we find life. Life is resilient and adaptable and small micro organisms have been found in thriving in extreme environments once thought too hostile to support life.

Expensive space missions to Europa to drill through the icy crust in the hope of finding life are now being rewritten to allow for more economically viable missions to “catch a whiff” of life in the vapor as they fly through.

Europa was discovered by Galileo in 1610 when he turned a telescope on Jupiter. From mid October Jupiter appears in the predawn sky and curious readers with a decent pair of binoculars can spot Europa as one of 4 tiny dots of light strung out on either side of the planet.