Is there life elsewhere in the solar system? There is no answer to this question yet, but there are some places that scientists are looking into. Enceladus is firmly in first place.
The space photo of the week is a beautiful photo of Enceladus. This moon revolves around the planet Saturn. The 500 kilometer wide moon is very cold and completely covered with ice. Enceladus has been regularly photographed by the Cassini spacecraft. In 2017, the Cassini mission came to an end and the spacecraft burned up in Saturn’s atmosphere. In 2017, visitors to Scientias.nl chose the 40 most beautiful Cassini photos, with the photo below of Enceladus coming out as the winner.
This mosaic consists of 28 different photos that are glued together. The photos were taken in 2008.
Beneath the frozen surface is a 40-mile thick ocean. In 2019, scientists wrote in the journal Science that this underground ocean is being enriched with hydrogen gas. This could well be a source of life. Hydrogen gas is entering the ocean thanks to hydrothermal activity at the bottom of the ocean. Researchers thus show that the three basic ingredients for life – liquid water, an energy source for metabolism and the right chemical ingredients – are almost all present. Only phosphorus and sulfur have not yet been found, but that is only a matter of time.
Plumes of water contain ingredients for amino acids
The moon regularly spouts towering plumes of water into space. Researchers recently found new organic compounds in these plumes. These compounds that carry nitrogen and oxygen play a key role in the production of amino acids: complex molecules that serve as the building blocks for proteins. Without these proteins, life as we know it on Earth could not exist. “We don’t yet know whether amino acids are necessary for extraterrestrial life, but finding the molecules that make up amino acids is an important piece of the puzzle,” said researcher Nozair Khawaja.
Enceladus sprays water into space. Hopefully one day we will be able to analyze this water and find out if there are any signs of life.
No mission to Enceladus, but to Titan
Scientists hope to look under the ice of Enceladus one day, but unfortunately no missions are planned yet. This is partly due to the fact that the ice sheet has an average thickness of twenty kilometers. At the South Pole, the ice sheet is thinner than five kilometers, but you still can’t drill through that. It is then more interesting to send a space probe with a radar instrument to Enceladus to ‘see’ under the ice in this way. Fortunately, other missions to Saturn and its moons are planned. For example, in 2036, the quadrocopter Dragonfly will explore the moon Titan. The drone will land in the Shangri-La dunes on Titan and then fly on to other places. The drone also collects samples from the surface. Scientists hope that Dragonfly will find building blocks of life and tell us more about the origin of life.