June 17, 2022
Louis Block Professor Nicolas Dauphas has been named one of the members of the Mars Sample Return Campaign Science Group. According to NASA, the Group "will be the standard-bearers for Mars Sample Return science. [...] They will build the roadmap by which science for this historic endeavor is accomplished – including establishing the processes for sample-related decision-making and designing the procedures that will allow the worldwide scientific community to become involved with these first samples from another world."
Samples are now being collected by the Perseverance rover for intended future return to Earth.
More information can be found at https://www.jpl.nasa.gov/news/nasa-partner-establish-new-research-group-for-mars-sample-return-program
And at UChicago News
June 15, 2022
“We really haven’t had a sample like this before. It’s spectacular.”-Andrew Davis
The rock is similar to a class of meteorites known as “Ivuna-type carbonaceous chondrites.” These rocks have a similar chemical composition to what we measure from the sun and are thought to date back to the very beginnings of the solar system approximately four-and-a-half billion years ago—before the formation of the sun, the moon and Earth.
“We previously only had a handful of these rocks to study, and all of them were meteorites that fell to Earth and were stored in museums for decades to centuries, which changed their compositions,” said geochemist Nicolas Dauphas, one of the three University of Chicago researchers who worked with a Japan-led international team of scientists to analyze the fragments. “Having pristine samples from outer space is simply incredible. They are witnesses from parts of the solar system that we have not otherwise explored.”
“By examining these samples, we can constrain the temperatures and conditions that must have been occurring in their lifetimes, and try to understand what happened,” Yokochi explained.
June 01, 2022
Early Mars had rivers, but the cause of Mars’s wet-to-dry transition remains unknown. Associate Professor Edwin Kite and graduate student Bowen Fan, together with co-authors from NASA, PSI, Aeolis Research, and the Smithsonian, analyzed global databases of water-worked landforms and identified changes in the spatial distribution of rivers over time. These changes are simply explained by comparison to a simplified meltwater model driven by an ensemble of global climate model simulations as the result of ≳10 K global cooling, from global average surface temperature T ≥ 268 K to T ~ 258 K, due to a weaker greenhouse effect. Unexpectedly, analysis of the greenhouse effect within Kite and Fan's ensemble of global climate model simulations suggests that this shift was primarily driven by waning non-CO2 radiative forcing, and not changes in CO2 radiative forcing. More details can be found at UChicago News. The research was published in Science Advances.