Ultima Thule, the Most Distant Object Man Has Visited, An Ocean on Pluto, and the Dawn and Rosetta Space Missions
Ultima Thule is the most distant object ever visited at 4.1 billion miles away and the New Horizon’s spacecraft passed within 3500km of it on January 1. The object is shaped like a rocky snowman and spins like a lopsided propeller facing the sun, tilted 90 deg from its orbit plane and is about 22 miles long. Its scientific interest lies in the fact that it was likely formed at the time of the formation of the solar system 4.5 billion years ago but has seen little change since then. Thus, it offers an opportunity to study the process by which planets were initially formed. The talk will explore the latest data from the mission and will also provide updates on the discovery of a buried ocean on Pluto.
The NASA Dawn space mission was launched in 2007 to explore two of the three proto planets in the solar system, Vesta and Ceres which are located in the asteroid belt between Mars and Jupiter. Ceres contains 200 million cubic kilometers of water in its mantle which is more than all of the fresh water on earth. Vesta is 220km in size and in contrast is a water poor world with a metallic iron nickel core. In this talk the detailed images of these asteroids will be presented and the very interesting geography and geology of both asteroids will be discussed. Vesta for example has some massive craters with one called Rheasilvia being 19km deep with a central peak 23km above the crater floor.
The last part of the talk will be about the ESA’s Rosetta mission to the comet Churyumov–Gerasimenko. It is the only mission to orbit a comet and it was able to study the comet as it moved towards the sun. One of its notable results was determining that the comet has a Deuterium to Hydrogen ration 3x higher than on earth. This strongly indicates that earth’s water is not likely to have come from comets.