Mystery giant Mars plumes still unexplained
On Feb. 16, an international group of researchers proposed new hypotheses about some unusual plumes spotted by amateur astronomers on Mars in 2012. The plumes were seen rising to altitudes of over 250 km above. By comparison, similar features seen in the past have never exceeded 100 km. Now, new conclusions presented by scientists still raise more questions about the mysterious plumes, than they answer. "We tentatively explored two scenarios that might help explain the observed phenomenon: a cloud of condensed CO2 or H2O, or even dust, and an aurora. After elaborating the details of these two hypotheses, we came to the conclusion that none of them provided a fully satisfactory answer," Antonio García Muñoz of ESA's European Space Research and Technology Centre (ESTEC), co-author of the paper reporting the results in the journal Nature, told astrowatch.net. "Therefore, we consider that the genuine nature of the phenomenon is still an...