May 12, 2017
University of Chicago graduate students Kara Lamb and Ben Clouser, postdoc Max Bolot, and Research Scientist Laszlo Sarkozy, working under the direction of Associate Professor Elisabeth Moyer, have carried out direct measurements of deuterium-hydrogen isotopic fractionation during ice deposition in simulated cirrus clouds at temperatures relevant to the polar regions of Earth and the near-surface atmospheric layers of Mars. The experiments used the Aerosol Interactions and Dynamics in the Atmosphere (AIDA) cloud chamber in Karlsruhe, Germany. The new data provide fundamental constraints that will improve confidence in the interpretation of deuterium isotopic variations in the atmospheres of both Earth and Mars. The results have been published in the Proceedings of the National Academy of Sciences.
May 11, 2017
Former DoGS postdoc and current assistant professor at Peking University Jun Yang, assistant professor Malte Jansen, and associate professor Dorian Abbot have published a new paper investigating the aftermath of snowball Earth (global glaciation) events. During a snowball Earth event about half of Earth's ocean was locked up in ice, and the remainder of the ocean was cold and salty. After the snowballs melted this cold, salty, dense layer was overlain with a warm, fresh, light layer made up of water that used to be ice. The new work shows that it took about 50,000 years for this density gradient to mix away, rather than the ~1,000 year mixing timescale of the modern ocean. This result is critical for geologists trying to understand the geochemical clues the snowball left behind.
May 02, 2017
Hubble Fellow Sebastian Krijt, TC Chamberlin Fellow Tim Bowling, graduate student Richard Lyons, and Professor Fred Ciesla have just published a new paper in which they show that it would be possible for life to be transported between the planets of the extra-solar system TRAPPIST-1 (panspermia). The mechanism would be asteroids slamming into one planet and knocking material onto another planet. Many forms of life can survive such an impact, travel through space, and entry through the atmosphere of another planet. Since the TRAPPIST-1 planets are very close together, this process is more liely.