Carolyn Porco

As far as I'm concerned, Enceladus has become the go-to place in our solar system for issues bearing on extraterrestrial life. It's a great place to examine extraterrestrial organic chemistry that is water-based and, therefore, like biotic chemistry on Earth.

I got into astronomy through an interest in religion.

Even if the ocean on Enceladus starts out being as microbially poor as the pelagic ocean on Earth, which is the worst case, we still have a chance of seeing lots of organisms in the plumes.

Cassini was so profoundly, scientifically successful. It's amazing to me, even, what we were able to do right up until the end.

The book that blew the doors off the house, grabbing me with its breathtakingly deep and irresistible view of the universe and our relation to it, was 'Intelligent Life in the Universe' by I. S. Shklovskii and Carl Sagan. I recall an enchanting all-nighter completing a college homework assignment to read the first chapter.

To my mind, most people go through life recoiling from its best parts. They miss the enrichment that just a basic knowledge of the physical world can bring to the most ordinary experiences.

I was drawn to astronomy by a teenage existential quest. Around 13, I was deep into wondering about the meaning of life and what I was doing here. I turned to religion, but that did nothing for me. I got to wondering where was here. So, I began studying astronomy and became enthralled by what I learned.

Titan has no liquid water on its surface, and any liquid water beneath its surface is inaccessible to us, as far as we know. It has hydrocarbon lakes, but we don't know of any organisms that could live in those, not at the temperatures that we find on Titan. Any reference to possible life in lakes on the surface of Titan is pure speculation.

Carl Sagan: A Life,' though a riveting tale, tells as much about the all-too-human feelings of jealousy and resentment as it does about the individual who inspired them.

Motive may be inferred only when the stimuli in the agent's environment are open to view and the influences leading an agent to a particular action can be evaluated.

Scientists tend to come in two stripes: those who have tremendous appetite and aptitude for the details, and those who illuminate the big picture. Sagan was definitely in the latter category, and he was profoundly good at it. He made connections that others did not have the intellectual breadth or courage to make.

Voyager's passage through Saturn's inner system exposed diverse moons with dynamic forces at work. Titan, Saturn's largest moon, whose surface remained invisible through its thick, ubiquitous haze, nonetheless teased observers with hints of a possible ocean of liquid hydrocarbons.