A new experiment that simulates the atmosphere of Titan has demonstrated that amino acids and nucleotide bases could be formed in the interactions between ultraviolet rays (like those from the sun) and methane and nitrogen (which make up Titan’s atmosphere). Amino acids and nucleotides are the necessary proto-molecules that you need to get DNA and RNA.
There are a number of likely ways in which the basic elements of live arose on Earth, like being formed by hydrothermal vents in the ocean, aquifers, lakes, or even brought here by comets. Scientists believe that modern Titan is in a state much like an ancient Earth, and so to say that these compounds are possible on Titan is to say that they may have occurred on Earth, too.
If this method is actually naturally occurring, outside of the lab, it means that, unlike previous thought, it may be possible to for the building blocks of life to arise on planets without water. Corroborating the lab-to-reality assumption is the fact that
the Cassini spacecraft detected heavy ions in Titan’s atmosphere, but they were too massive for the craft’s instruments to identify. Amino acids were among the potential candidates for those heavy compounds, which were found in the terrestrial simulation.
Unfortunately, confirming the identity of those ions would require a craft capable of penetrating 60-100 miles further into Titan’s atmosphere than Cassini did, so don’t look for progress on that question for a while.
(via Wired.)
