Dr. David Summers

Curriculum Vitae:

Dave Summers investigates a wide range of chemical reactions that are either needed for life to begin, that may affect whether life can exist, or that might be used by scientists to recognize life elsewhere. For example he is looking at the reactions of nitrogen in the atmosphere of ancient Mars. Where did it go? Could it have provided nitrogen for the start of life on Mars?

It may be that vesicles, water filled “soap bubbles” that look something like cells, may have been important in the origin of life. Dave is looking at what reactions may occur inside these vesicles, and how they may related to things like the start of photosynthesis.

Life shows a preference for using the lighter isotope of carbon – carbon-12 – rather than the slightly heavier carbon-13 when it makes stuff out of carbon dioxide. Can we use this as a test for whether compounds were made by life? Or might inorganic reactions do the same thing? Dave is doing the hard work of examining how this same preference for lighter carbon might also be exhibited by completely inorganic reactions. By understanding how this can happen, he may keep future space missions from stumbling over a false claim of extraterrestrial biology. He is also interested in how we can test for such compounds as proteins or fatty acids to detect life, both in the lab and robotic missions. Dave doesn’t just assume we’ll just “know life when we see it.” He wants a better test than that.

Adopt a Scientist Opportunity

Interested in the latest results from the lab? Wonder how people come up with those instruments they send to other planets? Want do know how scientists decide what planets used to be like? Work with Dave and be involved first-hand in current research on the chemistry of other planets and on ways to search for life. Your experience can range from finding out the latest results before anyone else, to getting into the lab to see how things are done. You can learn about planetary science while still being able to pick up a latte on the way home.

Projects

Modeling the Origin and Early Evolution of Life

NNX07AV18A   

This work will support the analysis an interpretation of a data from the field study of microbial ecosystems and lab work both on samples collected from the field and on theoretical systems. All of these will attempt to model or represent analogs for the origin and early evolution of life and/or provide data for the interpretation of such systems for NASA objectives. This covers; the development of techniques and data for the analysis of samples of astrobiological interests, from samples returns, to analysis of exogenous materials, to the detection of life and proteins, to the detection of microbial activity in extreme environments, the characterization of biogeological materials to better understand early life on Earth, its context, how it impacted the planet, and how it evolved (and, by extrapolation, how it started), and the laboratory modeling of processes that that may have occurred in the origin and early evolution of life so that we can better understand those processes and have specific theories to compare data against. This will involve both the analysis of biogeological samples collected in field and also samples produced by abiotic reactions (as a benchmark to compare samples of suspected biogenic origin against).