Transcript Document
Formation of Mercury By Triana Henz In the beginning… • There was a giant cloud of particles within the Milky Way • Particles start to rotate • The cloud starts to collapse on itself • A star is born at the center!! What takes place in a few Myr? • Accretion Theory takes place • Heavy elements make their way closer to the sun • A temperature difference takes place at about 4 AU, allowing the inner gas to be hotter Planets • Particles gather to form cosmic dust • Cosmic dust stick together to grow into small planet like objects • The small planet like objects collide with each other • As the dust clears, we have proto-planets!! Mercury • The out-liner of the inner planets • Has a high density, molten core, magnetic field, and a big core Thoughts on the mysteries • Theories have to account mostly for the high density that is observed • Most theories take place during the early stages of the solar system • Three leading theories: – Selective Accretion – Post-accretional vaporization – Giant impact Stripping Selective Accretion • Enrichment of iron that leads to the high density • Principles: – Needs mechanical and aerodynamic accretion processes – A low chemical equilibrium condensation temperature Why was iron so rich? • The solar nebula in the feeding zone was naturally rich with iron • Particles were so close to the Sun that it was reducing the other elements to a metallic form that had a high melting point to solidify • This process could explain why Mercury is highly density Post-accretional Vaporization • After Mercury was formed, the solar winds were strong enough to blow away the original surface • The solar winds would’ve contained intense solar electromagnetic and particle radiation Giant Impact Stripping • Object crashed into Mercury • Object needs to be about Mars size • The impact had blown away the upper layers of proto-Mercury Correct Theory? • • • • • • • Depending on when Mercury was impacted, the material ejected would need to go somewhere Candidates for where the material ended up are the Sun, Venus, and Earth The Solar Winds would most likely leave a few traces of the proto layers since the Solar Winds wouldn’t be able to make a near spherical object Chemical equilibrium condensation models for the solar nebula can’t account for a molten core at Mercury’s present orbit or density if formed between .4-1.4 AU The condensation models also need to take into account why Mercury is the only one that is affected by the lower temperature To know which of the theories is correct, chemical composition needs to be known of the surface Each would leave trace evidence of their existence since each has their own unique signature of oxides and iron oxides One More Thing… • There is no doubt that the position of Mercury gives itself to an unique formation • It has us believing that we’ll know our solar system and all planet formation if we study it closely • And now we look