A Pathway to Protocells on Titan – Animations

Zoom in on Saturn’s ring plane to reveal Titan, the only place in the solar system besides Earth that is known to have large lakes on its surface.Credit: NASA Goddard/CI Lab

Titan’s clouds part to reveal an icy landscape stained by organic molecules. In the distance, a hydrocarbon lake is slicked with an iridescent sheen.Credit: NASA Goddard/CI Lab

Acrylonitrile molecules drift through Titan’s atmosphere. These simple organics could form membrane-like bubbles called “vesicles” within Titan’s lakes.Credit: NASA Goddard/CI Lab

Methane rain falls into a hydrocarbon lake, delivering the chemical ingredients and the kinetic energy needed to form membrane-like bubbles. The view tilts upward to a methane rain cloud.Credit: NASA Goddard/CI Lab

Sunlight drives chemical reactions in Titan’s upper atmosphere. Methane and molecular nitrogen are broken apart and reassembled into the organic molecules needed to form protocell-like bubbles.Credit: NASA Goddard/CI Lab

A large raindrop falls into a methane lake, which is covered by a layer of acrylonitrile molecules. The raindrop splashes up small droplets of methane coated in a single layer of acrylonitrile.Credit: NASA Goddard/CI Lab

A methane droplet falls and sinks back into the lake. As it passes through the surface, it receives a second coating of acrylonitrile, creating a protocell-like bubble called a vesicle.Credit: NASA Goddard/CI Lab

If vesicles in Titan’s lakes have more stable and less stable mixes of amphiphiles, the most stable would eventually become predominant – an evolutionary process that could lead to the formation of simple protocells.Credit: NASA Goddard/CI Lab

Cross section of a cell membrane in a terrestrial organism. Cell membranes are composed of a lipid bilayer that separates the cell from its environment, along with membrane proteins that help to carry out vital functions.Credit: NASA Goddard