Lowell Observatory

New Horizons Images of Pluto Revealed Valley Networks and Channels With a Variety of Morphologies Suggestive of the Erosive Action of Fluid. Their Discovery Was Startling as No Material Is Known That Is Stable as a Liquid Under the Temperature and Pressure Conditions Prevalent on Pluto's Present-day Surface. Various Hypotheses Have Been Proposed to Account for These Features Including Their Being Formed Through Glacial Rather Than Fluvial Action or That Liquids Could Have Existed on Pluto's Surface During Extreme Climatic Episodes in the Past. We Propose to Test Another Hypothesis: That Low Melting Point Mixed Fluids Could Exist Even at the Extremely Cold Temperatures and Low Pressures Prevalent in the Kuiper Belt Today. the Antifreeze Effects on Water of Salt or Alcohol Are Familiar. Such Freezing Point Suppression Is a Common Feature of Mixtures. Examples Involving Materials Known to Be Present at Pluto's Surface Include N2 + CH4 (a Small Effect) and CH4 + C2H6 (a Much Larger Effect). We Propose to Test Our Hypothesis via a Practical and Cost-effective Combination of Theoretical and Laboratory Techniques. This Approach Enables Us to Screen Many More Combinations Than We Could Ever Hope to Do in the Laboratory by Progressing From Inexpensive and Straightforward Calculations Through a More Substantial Investment in More Detailed Numerical Simulations and Finally to Time-consuming and Expensive Laboratory Confirmations. Each Step of This Chain We Invest More Time and Effort in Smaller Subsets of Potential Mixtures Homing in on Those That Possess Especially Interesting Properties. Each Approach Can Benefit From Work on the Others So It Is Natural to Combine Them Within a Coordinated Investigation. the Proposed Project Is Relevant to the Solar System Workings Program Element Because It Offers a Scientific Investigation Into the Physical and Chemical Properties of What Could Be a Key Class of Geological Materials in the Far Outer Solar System Specifically Fluids That Could Form in the Surface or Near-surface Environments of Bodies Such as Pluto Triton Eris Makemake and Haumea. If as We Hypothesize Such Fluids Can Exist They Could Enable a Rich Palette of Geological Processes to Operate on These Bodies Revolutionizing Understanding of Geology in the Outer Solar System.