Watson Lecture: Ceres and the Dawn of the Solar System

The main asteroid belt contains millions of objects but only a few date from the earliest stages of planet formation. The Dawn mission, managed by NASA's Jet Propulsion Laboratory (JPL), explored two such fossils: protoplanet Vesta and dwarf planet Ceres, the latter of which the spacecraft began to explore in March 2015. Since then, the mission has gathered evidence of geologic activity and clues confirming that Ceres had an ancient subsurface ocean, placing the dwarf planet in the important class of objects with astrobiological potential.

On Wednesday, November 9, Carol Raymond, the deputy principal investigator for the Dawn mission, will discuss the mission's results. This Watson Lecture begins at 8:00 p.m. and is free to the public.

What do you do?

I am a planetary scientist with a focus on the geophysical nature of planetary bodies and what that can tell us about how they formed. In particular, I study the shape and detailed topography, and magnetic and gravity fields to understand the internal workings of these bodies and the tectonic processes that modify them. My current focus is on exploring the large building blocks of the planets, represented by Vesta and Ceres. I also am involved in the exploration of the subsurface ocean of Europa, one of Jupiter's moons.

Why is this important?

While our solar system's planets and moons are relatively well understood, the processes that formed them during the early days of our solar system are still debated. Many factors influence the diversity of bodies that we see today in our solar system, including the distribution of solids, volatile gases, and ices and dynamic processes that redistributed them during and following planet formation. Studying the building blocks of the planets sheds light on this complex evolution and on habitable zones in our planetary neighborhood.

How did you get into this line of work?

Science, in general, and physics in particular, were my main interests in school. I also love to observe and explore. Seeing a new landscape or an alien world for the first time is a thrill. But then gathering all the evidence and unraveling the story of how planetary bodies form and change is the real prize. After studying Earth's plate tectonics and the history of its ice sheets, using ships, planes, and satellites, I became interested in applying these same techniques to studying the fossils from the early solar system, which led to my current role exploring the asteroid belt.

Named for the late Caltech professor Earnest C. Watson, who founded the series in 1922, the Watson Lectures present Caltech and JPL researchers describing their work to the public. Many past Watson Lectures are available online at Caltech's iTunes U site.