One idea for fighting global warming is to increase the amount of aerosols in the atmosphere, scattering incoming solar energy away from the Earth’s surface. But scientists theorize that this solar geoengineering could have a side effect of whitening the sky during the day. New research from Carnegie’s Ben Kravitz and Ken Caldeira indicates that blocking 2% of the sun’s light would make the sky three-to-five times brighter, as well as whiter.
Until now, Earth was the only planet known to have vast reservoirs of water in its interior. Scientists analyzed the water content of two Martian meteorites originating from inside the Red Planet. They found that the amount of water in places of the Martian mantle is vastly larger than previous estimates and is similar to that of Earth’s. The results not only affect what we know about the geologic history of Mars, but also have implications for how water got to the Martian surface. The data raise the possibility that Mars could have sustained life.
In the search for Earth-like planets, it is helpful to look for clues and patterns that can help scientist narrow down the types of systems where potentially habitable planets are likely to be discovered. New research from a team including Carnegie’s Alan Boss narrows down the search for Earth-like planets near Jupiter-like planets. Their work indicates that the early post-formation movements of hot-Jupiter planets probably disrupt the formation of Earth-like planets.
Molecules containing large chains of carbon and hydrogen--the building blocks of all life on Earth--have been the targets of missions to Mars from Viking to the present day. While these molecules have previously been found in meteorites from Mars, scientists have disagreed about how this organic carbon was formed and whether or not it came from Mars. A new paper provides strong evidence that this carbon did originate on Mars, although it is not biological. These findings give researchers insight into the chemical processes taking place on Mars and will help aid future quests for evidence of ancient or modern Martian life.
Type Ia supernovae are important stellar phenomena, used to measure the expansion of the universe. But astronomers know embarrassingly little about the stars they come from and how the explosions happen. New research from a team led by Harvard University and including Carnegie’s Josh Simon, Chris Burns, Nidia Morrell, and Mark Phillips examined 23 Type Ia supernovae and helped identify the formation process for at least some of them.
Insect glands are responsible for producing a host of secretions that allow bees to sting and ants to lay down trails to and from their nests. New research from Carnegie scientists focuses on secretions from glands in the reproductive tract that help sperm survive and guide the sperm on the trip to fertilize an egg. The gene that controls the development of these glands in fruit flies provides important information about gland development in all insects, as well as potential clues to similar human reproductive glands.
For the first time, astronomers have detected the presence of arsenic and selenium, neighboring elements near the middle of the periodic table, in an ancient star in the faint stellar halo that surrounds the Milky Way. Arsenic and selenium are elements at the transition from light to heavy element production, and have not been found in old stars until now.
How hydrogen--the most abundant element in the cosmos--responds to extremes of pressure and temperature is one of the major challenges in modern physical science. Moreover, knowledge gleaned from experiments using hydrogen as a testing ground on the nature of chemical bonding can fundamentally expand our understanding of matter. New work from Carnegie scientists has enabled researchers to examine hydrogen under pressures never before possible.
Ben Kravitz, post-doctoral research scientist at the Carnegie Institution for Science's Dept. of Global Ecology on the Stanford University campus discussing: B. Kravitz, D.G. MacMartin, and K. Caldeira Geoengineering: Whiter skies? GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L11801, 6 PP., 2012 doi:10.1029/2012GL051652 http://dge.stanford.edu/labs/caldeiralab http://www.stanford.edu/~bkravitz/ http://www.agu.org/pubs/crossref/2012/2012GL051652.shtml
Ken Caldeira, climate scientist at the Carnegie Institution for Science's Dept. of Global Ecology on the Stanford University campus discussing: Pongratz, J., and K. Caldeira, 2012: Attribution of atmospheric CO2 and temperature increases to regions: importance of preindustrial land use change. Environmental Research Letters, Vol. 7, 034001 doi:10.1088/1748-9326/7/3/034001 http://dge.stanford.edu/labs/caldeiralab http://www.mpimet.mpg.de/en/staff/julia-pongratz.html The underlying paper is available for free download at: http://iopscience.iop.org/1748-9326/7/3/034001/
Scientists have long speculated about why there is a large change in the strength of rocks that lie at the boundary between two layers immediately under Earth’s crust: the lithosphere and underlying asthenosphere. Understanding this boundary is central to our knowledge of plate tectonics and thus the formation and evolution of our planet as we know it today. A new technique for observing this transition, particularly in the portion of Earth’s mantle that lies beneath the Pacific Ocean basin, has led Carnegie and NASA Goddard scientist Nick Schmerr to new insight on the origins of the lithosphere and asthenosphere.
As reported in one of two papers published on Science Express, scientists have found that Mercury’s core, already suspected to occupy a greater fraction of the planet's interior than do the cores of Earth, Venus, or Mars, is even larger than anticipated. The companion paper shows that the elevation ranges on Mercury are much smaller than on Mars or the Moon and indicates that there have been large-scale changes to Mercury’s topography since early in the planet’s geological history.
The Plant Metabolic Network (http://www.plantcyc.org/), which is based at Carnegie’s Department of Plant Biology, has launched four new online databases that offer an unprecedented view of the biochemical pathways controlling the metabolism of corn, soybeans, wine grapes, and cassava—four important species of crop plant. The new databases will serve as a critical resource for scientists working with these species to increase crop production, enhance biofuel development, or explore novel medicines.
A team of astronomers has discovered the most distant cluster of red galaxies ever observed using FourStar, a new and powerful near-infrared camera on the 6.5m Magellan Baade Telescope. The galaxy cluster is located 10.5 billion light years away in the direction of the constellation Leo. It is made up of 30 galaxies packed closely together, forming the earliest known “galaxy city” in the universe.
Plant science is key to addressing the major challenges facing humanity in the 21st Century, according to Carnegie’s David Ehrhardt and Wolf Frommer. In a Perspective published in The Plant Cell, the two researchers argue that the development of new technology is key to transforming plant biology in order to meet human needs.
Eta Carinae, one of the most massive stars in our Milky Way galaxy, unexpectedly increased in brightness in the 19th century. For ten years in the mid-1800s it was the second-brightest star in the sky. (Now it is not even in the top 100.) The increase in luminosity was so great that it earned the rare title of Great Eruption. New research from a team including Carnegie’s Jose Prieto, now at Princeton University, has used a “light echo” technique to demonstrate that this eruption was much different than previously thought.
By analyzing submarine volcanic glass from the Manus Basin, scientists found unexpected changes in hydrogen and boron isotopes from the deep mantle. They expected to see the “fingerprint” of seawater. But discovered evidence of seawater distilled from a more ancient plate descent, preserved for as long as 1 billion years. The data indicate that these ancient “slabs” can return to the upper mantle, and that rates of hydrogen exchange may not conform to experiments.
The major difference between plant and animal cells is the photosynthetic process, which converts light energy into chemical energy. When light isn’t available, energy is generated by breaking down carbohydrates and sugars, just as it is in animal and some bacterial cells. Two cellular organelles are responsible for these two processes: the chloroplasts for photosynthesis and the mitochondria for sugar breakdown. New research from Carnegie’s Eva Nowack and Arthur Grossman has opened a window into the early stages of chloroplast evolution.
Superconductivity is a rare physical state in which matter is able to conduct electricity—maintain a flow of electrons—without any resistance. This phenomenon can only be found in certain materials at low temperatures, or can be induced under chemical and high external pressure conditions. Research to create superconductors at higher temperatures has been ongoing for two decades with the promise of significant impact on electrical transmission. New work demonstrates unexpected superconductivity in a type of compounds called iron selenium chalcogenides.
By combining airborne laser technology, satellite mapping, and ground-based plot surveys, a team of researchers has produced the first large-scale, high-resolution estimates of carbon stocks in remote and fragile Madagascar. The group has shown that it is possible to map carbon stocks in rugged geographic regions and that this type of carbon monitoring can be successfully employed to support conservation and climate-change mitigation under the United Nations initiative on Reduced Emissions from Deforestation and Degradation (REDD).