An NSF Press Release indicates that astronomers Jean-Luc Margot of Cornell University, Stan Peale of the University of California, Santa Barbara, Ray Jurgens and Martin Slade of the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., and Igor Holin of the Space Research Institute in Russia will report their findings in the cover story of the May 4, 2007, journal Science.
These scientists used ground-based radio telescopes to measure minute wobbles in the motion of the planet Mercury, and have discovered strong evidence that Mercury has a molten core.
“So what?” you say? This is cutting edge science, and an incredible leap forward in the remote detection of geologic features on other planets. This technology, now that it has been developed, could be refined and perhaps eventually be used to look for similar conditions on extra-solar planets.
This is the kind of stuff that the average person-on-the-street may think “Why is this a big deal?”. I’m thinking “Get out of the street before the bus runs you over!”. It is a big deal. We now have another tool in our arsenal that can determine if a planet is earth-like. Science like this is used to test our assumptions. There was a question up in the air: Does Mercury have a solid core, or a molten core? Some thought it would be nearly pure iron, and therefore solid. Others thought it would be molten due to the presence of contaminants like sulfur (which would lower the melting point of the core). It looks like the molten-core theorists are on the right track.
This will tell us more about the formation of our solar system, and possibly the formation of other solar systems. Perhaps we can now look at Venus, and Mars to determine if they have solid or molten cores.