Sue Smrekar

I study the global processes that shape the interior, surface, and atmosphere of Venus – Earth’s twin. These two planets are a cosmic gift to those studying rocky planet evolution. No two planets are more similar in size, overall composition, and energy from the sun. Earth is still the only known abode for life, while Venus could stand in for Dante’s hell. Its clouds rain sulfuric acid and its surface is hot enough to melt lead. The surface pressure from its immense carbon dioxide atmosphere is equivalent to a being under a kilometer of water. Yet Venus could have been the first habitable planet with liquid water in our solar system.  Many of the geologic processes on the surface are much like Earth’s: volcanoes, large plateaus like our continents, and tectonic deformation. Understanding the mystery of how these two planets diverged so dramatically is key to understanding rocky planet habitability

Venus is the brightest object in the night sky, after the moon. Thus it features prominently in many indigenous cosmologies. The Mayans in particular built temples to track Venus and aligned significant events with Venus’ path. I take photos of Venus wherever I go, even in big cities.  I think the immense expanse of the night sky, and Venus’ brilliance, still has the power to inspire us to rise above our immediate concerns, perhaps imaging a positive vision for our home planet. Similarly, the immense power of a rocket escaping Earth’s gravity carrying either human or robotic explorers frees one to imagine worlds different than our own.  My hope for the future is that science will not only improve people’s lives but inspire creativity and connection to a purpose larger than ourselves. 

My dream is to find out what makes Venus tick.  Venus gets called Earth’s evil twin based on its 900°F surface. But that hot temperature means that the near-surface rock layer, the lithosphere, is likely a lot like early Earth’s while it was still cooling. Several billion years ago, Earth’s lithosphere broke into plates, the continents formed, and life began to flourish. But what caused the plates to form and develop into the current system of plate tectonics is not known.  Most evidence has been erased by erosion or plates sinking into the interior at subduction zones. Venus today has the likely precursors to Earth’s plate tectonics – localized subduction zones without complete plates and possible proto-continents.  Studying these features will us help us understand how plate tectonics and continents formed on Earth.