High concentrations of iridium have been reported in terrestrial sediments dated at 12.9 ka and are interpreted to support an extraterrestrial impact event as the cause of the observed extinction in the Rancholabrean fauna, changes in the Paleoindian cultures, and the onset of the Younger Dryas cooling [Firestone RB, et al. (2007) Proc Natl Acad Sci USA 104:16016-16021]. Here, we report platinu...

SETI@home, a search for signals from extraterrestrial intelligence, has been recording data at the Arecibo radio telescope since 1999. These data are sent via the Internet to the personal computers of volunteers who have donated their computers' idle time toward this search. The SETI@home client software, which runs on these computers, corrects the data for a wide variety of possible accelerati...

Abstract-Silicate and glassy spherules of probably extraterrestrial origin have been discovered in glacial till from localities in the Beardmore glacier region, Tramantarctic Mountains, Antarctica. These spherules are similar in structure, appearance, and composition to spherules found in deepsea sediments and in Greenland. Most spherules have a shiny and smooth dark surface, while some show a ...

The coincidence of the Late Heavy Bombardment (LHB) period and the emergence of terrestrial life about 4 billion years ago suggest that extraterrestrial impacts could contribute to the synthesis of the building blocks of the first life-giving molecules. We simulated the high-energy synthesis of nucleobases from formamide during the impact of an extraterrestrial body. A high-power laser has been...

i am delighted to announce completion of the second issue of the new journal of “geopersia”, a product of the new era of replacing the persian language journals with specific english-language ones. our purpose is to provide a journal that offers a multi-disciplinary analysis of issues concerning geology subjects (i.e. sedimentology, stratigraphy, paleontology, petroleum geology, engineering geo...

As magmas rise toward the surface, they traverse regions of the mantle and crust with which they are not in equilibrium; to the extent that time and the intimacy of their physical contact permit, the melts and country rocks will interact chemically. We have modeled aspects of these chemical interactions in terms of ion-exchange processes similar to those operating in simple chromatographic colu...