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New Projection Shows Global Food Demand Doubling by 2050

By Guest PostNovember 24, 2011Economy, Generalagricultural land, agricultural practices, agronomic practices, belinda befort, carbon dioxide, christian balzer, david tilman, earth, ecosystems, Environment, environmental effects, extinction of species, global agriculture, global food demand, greenhouse gas emissions, human prosperity, jason hill, nitrogen, nitrogen fertilizers, poorer countries, saran twombly, technology transfer, united states, university of minnesota, yield

*Increasing yield in poorer countries could decrease adverse environmental effects*

Global food demand could double by 2050, according to a new projection reported this week in the journal Proceedings of the National Academy of Sciences (PNAS).

The analysis also shows that the world faces major environmental challenges unless agricultural practices change.

Scientists David Tilman and Jason Hill of the University of Minnesota (UMN) and colleagues found that producing the amount of food needed could significantly increase levels of carbon dioxide and nitrogen in the environment, and may cause the extinction of numerous species. (more…)

A Tailored Pair of Genes

By Guest PostNovember 22, 2011Scienceagriculture, alfalfa like legume, ancestor of legumes, ancestral genes, ancient plants, asteroid, backbone of protein, bacteria, beans, cretaceous period, crop plants, demise of the dinosaurs, dinosaurs, disaster, earth, eggs, fertilizers, genes, genetically engineer legumes, genomes, humans, legumes, living together, major nutrient, medicago truncatula, model, nevin young, nitrogen, nitrogen and phosphorus fertilizer, nitrogen fixation, nitrogen fixing bacteria, nonsynthetic nitrogen fertilizer, peanuts, peas, sequencing genome, soybeans, sperm, synthetic fertilizer, university of minnesota

*For ancient plants, two genes were definitely better than one*

In the wake of the disaster that killed the dinosaurs, the ancestors of today’s crop plants reinvented themselves.

They doubled their genomes, and in that single act set the stage for feeding the world 60 million years later.

In a study published in the Nov. 16 issue of the journal Nature, researchers from the University of Minnesota and other institutions recount how sequencing the genome of a model, alfalfa-like legume revealed the monumental benefits that flowed when the ancestor of legumes acquired an extra copy of every gene. (more…)

Voyager 2 Completes Switch to Backup Thruster Set

By Guest PostNovember 15, 2011Sciencebackup thrusters, deep space network, earth, engineers, heliosheath, interstellar space, NASA, power requirements, pressure of interstellar gas, rate of energy, solar system, spacecraft, voyager 1 and voyager 2, voyager 2

PASADENA, Calif. — NASA’s Voyager 2 has successfully switched to the backup set of thrusters that controls the roll of the spacecraft. Deep Space Network personnel sent commands to the spacecraft to make the change on Nov. 4 and received confirmation today that the switch has been made.

The change allows engineers to reduce the amount of power that the 34-year-old spacecraft needs to operate by turning off the heater that keeps the fuel to the primary thrusters warm. Although the rate of energy generated by Voyager 2’s nuclear power source continues to decline, by reducing its power requirements, engineers expect the spacecraft can continue to operate for another decade. (more…)

Newly Found Dwarf Galaxies Could Help Reveal the Nature of Dark Matter

By Guest PostNovember 12, 2011Scienceandromeda, andromeda xxviii and xxix, astronomers, colin slater, dwarf galaxies, dwarf galaxies around andromeda, dwarf spheroidal galaxy 200 kpc from andromeda, earth, eric bell, gemini north telescope, gravitational effects, gravity, hawaii, how matter relates to dark matter, hypothesis, invisible substance, light years, night sky, predictions, satellites of andromeda, sloan digital sky survey, spiral galaxy, star counting technique, telescopes, understanding of dark matter, universe mass, university of michigan

ANN ARBOR, Mich.— In work that could help advance astronomers’ understanding of dark matter, University of Michigan researchers have discovered two additional dwarf galaxies that appear to be satellites of Andromeda, the closest spiral galaxy to Earth.

Eric Bell, an associate professor in astronomy, and Colin Slater, an astronomy Ph.D. student, found Andromeda XXVIII and XXIX—that’s 28 and 29. They did it by using a tested star-counting technique on the newest data from the Sloan Digital Sky Survey, which has mapped more than a third of the night sky. They also used follow-up data from the Gemini North Telescope in Hawaii. (more…)

NASA Captures New Images of Large Asteroid Passing Earth

By Guest PostNovember 8, 2011Science2005 yu55, aircraft carrier sized asteroid, asteroid, asteroid 2005 yu55, deep space network antenna, earth, flyby, goldstone, hazardous to planet, jet propulsion laboratory, moon orbit, NASA, radar images, spaceguard, trajectory of asteroid, venus and mars

PASADENA, Calif. –– NASA’s Deep Space Network antenna in Goldstone, Calif. has captured new radar images of Asteroid 2005 YU55 passing close to Earth.

The asteroid safely will safely fly past our planet slightly closer than the moon’s orbit on Nov. 8. The last time a space rock this large came as close to Earth was in 1976, although astronomers did not know about the flyby at the time. The next known approach of an asteroid this size will be in 2028. (more…)

NASA’s Spitzer Detects Comet Storm in Nearby Solar System

By Guest PostOctober 20, 2011Sciencealien solar system, almahata sitta meteorite, bright star in the northern sky, carey lisse, comets, dark seas, earth, Epoch, eta corvi, hailstorm, kuiper belt, late heavy bombardment, man in the moon, maria, NASA, solar system, spitzer space telescope

PASADENA, Calif. — NASA’s Spitzer Space Telescope has detected signs of icy bodies raining down in an alien solar system. The downpour resembles our own solar system several billion years ago during a period known as the “Late Heavy Bombardment,” which may have brought water and other life-forming ingredients to Earth.

During this epoch, comets and other frosty objects that were flung from the outer solar system pummeled the inner planets. The barrage scarred our moon and produced large amounts of dust. (more…)

Extreme Space Weather at Mercury Blasts the Planet’s Poles

By Guest PostOctober 4, 2011Scienceatmosphere, aurora borealis, charged particles, earth, exosphere, fast imaging plasma spectrometer, fips, fundamental science about the sun, jim raines, magnetosphere, mercury, messenger spacecraft, NASA, oxygen particles, polar regions, sodium, solar system, solar wind sandblasts, space environment, squall of hot plasma, surface of planet mercury, thomas zurbuchen, university of michigan

ANN ARBOR, Mich.— The solar wind sandblasts the surface of planet Mercury at its poles, according to new data from a University of Michigan instrument on board NASA’s MESSENGER spacecraft.

The sodium and oxygen particles the blistering solar wind kicks up are the primary components of Mercury’s wispy atmosphere, or “exosphere,” the new findings assert. Through interacting with the solar wind, they become charged in a mechanism that’s similar to the one that generates the Aurora Borealis on Earth. (more…)

Deep Oceans May Mask Global Warming for Years at a Time

By Guest PostSeptember 22, 2011Environmentatlantic, climate system, community climate system model, computer simulations of global climate, coupled model intercomparison project phase 5, earth, el niño, eric deweaver, gerald meehl, global air temperatures, greenhouse gas, ice and snow, john fasullo, kevin trenberth, la niña, missing heat, national center for atmospheric research, ncar, oceanic circulation, rate of global warming, software tool, temperature, tropical pacific, warming the upper ocean

*Computer simulations of global climate lead to new conclusions*

Earth’s deep oceans may absorb enough heat at times to flatten the rate of global warming for periods of as long as a decade–even in the midst of longer-term warming. This according to a new analysis led by scientists at the National Center for Atmospheric Research (NCAR).

The study, based on computer simulations of global climate, points to ocean layers deeper than 1,000 feet as the main location of the “missing heat” during periods such as the past decade when global air temperatures showed little trend. (more…)

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