How Titan might be making DNA building blocks
Saturn's moon Titan has many of the components for life – but no liquid water. A new study shows how the moon's atmosphere might be producing the molecules that make up DNA anyway.
The orange hydrocarbon haze that shrouds Saturn's frosty moon Titan could be creating the molecules that make up DNA without the help of water – an ingredient widely thought to be necessary for the molecules' formation.
What's more, it could be doing this with help from an unexpected source: another moon of Saturn some 610,000 miles away.
Just because Titan's atmosphere is creating these molecules doesn't mean that the molecules are combining to form life, caution the researchers from the US and France who conducted the experiments. But the results could prompt astrobiologists to consider a wider range of extrasolar planets as potential hosts for at least simple forms of organic life, the team of scientists from the US and France suggests.
Moreover, the results could offer greater insight into how life on Earth formed.
Although Titan is far colder than the early Earth would have been, the makeup of its atmosphere is thought to be comparable to that of Earth's billions of years ago. The new findings suggest that on the early Earth, the planet's upper atmosphere – not just the so-called primordial soup on the surface – may have been the sources for these "prebiotic" molecules, amino acids and the so-called nucleotide bases that make up DNA.