Habitable Zones & Global Climate: April 2012

Geological background of the samples analyzed in this study. Panel A shows the geological map at Marble Bar and the location of the ABDP-1 drill core. Panel B shows the simplified stratigraphic column of the lower part of the Pilbara Supergroup, with ages constrained by zircon U-Pb geochronology.

Astrobiologists from NAI's team at the University of Wisconsin, Madison have recently published a study of drill cores obtained through the NAI-funded Archean Biosphere Drilling Project which sampled the 3.4 billion year old Apex Basalt from the Pilbara Craton in Western Australia. Their innovative approach directly dates oxidation products of the ancient rock, and they show that oxidation occurred in the Phanerozoic during deep weathering. Their results indicate that oxidation of the Apex Basalt did not occur in the Archean, and therefore cannot be used to infer an oxygenated atmosphere at that time. Their paper appears in Earth and Planetary Science Letters.

NASA's research for furthering our understanding of atmospheric composition is geared to providing an improved prognostic capability for such issues (e.g., the recovery of stratospheric ozone and its impacts on surface ultraviolet radiation, the evolution of greenhouse gases and their impacts on climate, and the evolution of tropospheric ozone and aerosols and their impacts on climate and air quality). The modeling and analysis effort is generally aimed at the questions of tropospheric air quality and oxidation efficiency, pollution sourced aerosol where they impact cloud properties, stratospheric chemistry and ozone depletion, and chemistry/climate interactions.

This amendment delays the proposal due date for Appendix A.16 Atmospheric Composition: Modeling and Analysis Program (ACMAP). This will give more time to proposers and better align the selection timeframe with the availability of new fiscal year funds.

The new proposal due date for Appendix A.16 ACMAP, is now October 1, 2012. Notices of Intent are not requested for this program. Table 2 and Table 3 of the Summary of Solicitation for this NRA will be updated to reflect these changes.

On March 12, 2012, this Amendment to the NASA Research Announcement "Research Opportunities in Space and Earth Sciences (ROSES) 2012" (NNH12ZDA001N) was posted on the NASA research opportunity homepage at and appears on the RSS feed at:

Questions concerning A.16 ACMAP, may be addressed to Richard Eckman, Earth Science Division, Science Mission Directorate, NASA Headquarters, Washington, DC 20546-0001. Email:; Telephone: 202-358-2567.