Fossil-hunting expeditions to Tanzania, Zambia and Antarctica provide new insights
Predecessors to dinosaurs missed the race to fill habitats emptied when nine out of 10 species disappeared during Earth’s largest mass extinction 252 million years ago.
Or did they?
That thinking was based on fossil records from sites in South Africa and southwest Russia.
It turns out, however, that scientists may have been looking in the wrong places. (more…)
PASADENA, Calif. – NASA’s Cassini spacecraft has provided scientists the first close-up, visible-light views of a behemoth hurricane swirling around Saturn’s north pole.
In high-resolution pictures and video, scientists see the hurricane’s eye is about 1,250 miles (2,000 kilometers) wide, 20 times larger than the average hurricane eye on Earth. Thin, bright clouds at the outer edge of the hurricane are traveling 330 mph(150 meters per second). The hurricane swirls inside a large, mysterious, six-sided weather pattern known as the hexagon. (more…)
When blessed with a resource in overwhelming abundance it’s generally a good idea to make valuable use of that resource. Lignocellulosic biomass is the most abundant organic material on Earth. For thousands of years it has been used as animal feed, and for the past two centuries has been a staple of the paper industry. This abundant resource, however, could also supply the sugars needed to produce advanced biofuels that can supplement or replace fossil fuels, providing several key technical challenges are met. One of these challenges is finding ways to more cost-effectively extract those sugars. Major steps towards achieving this breakthrough are being taken by researchers at the U.S. Department of Energy (DOE)’s Joint BioEnergy Institute (JBEI).
“Through the tools of synthetic biology, we have engineered healthy plants whose lignocellulosic biomass can more easily be broken down into simple sugars for biofuels,” says Dominique Loque, who directs the cell wall engineering program for JBEI’s Feedstocks Division. “Working with the model plant, Arabidopsis, as a demonstration tool, we have genetically manipulated secondary cell walls to reduce the production of lignin while increasing the yield of fuel sugars.” (more…)
A new look at conditions after a Manhattan-sized asteroid slammed into a region of Mexico in the dinosaur days indicates the event could have triggered a global firestorm that would have burned every twig, bush and tree on Earth and led to the extinction of 80 percent of all Earth’s species, says a new University of Colorado Boulder study.
Led by Douglas Robertson of the Cooperative Institute for Research in Environmental Sciences, or CIRES, the team used models that show the collision would have vaporized huge amounts of rock that were then blown high above Earth’s atmosphere. The re-entering ejected material would have heated the upper atmosphere enough to glow red for several hours at roughly 2,700 degrees Fahrenheit — about the temperature of an oven broiler element — killing every living thing not sheltered underground or underwater. (more…)
Billions of trees killed in the wake of mountain pine beetle infestations, ranging from Mexico to Alaska, have not resulted in a large spike in carbon dioxide released into the atmosphere, contrary to predictions, a UA-led study has found.
Massive tree die-offs release less carbon into the atmosphere than previously thought, new research led by the University of Arizona suggests.
Across the world, trees are dying in increasing numbers, most likely in the wake of a climate changing toward drier and warmer conditions, scientists suspect. In western North America, outbreaks of mountain pine beetles (Dendroctonus ponderosae) have killed billions of trees from Mexico to Alaska over the last decade. (more…)
University of Montreal researchers found that changes in gravity affect the reproductive process in plants. Gravity modulates traffic on the intracellular “highways” that ensure the growth and functionality of the male reproductive organ in plants, the pollen tube. “Just like during human reproduction, the sperm cells in plants are delivered to the egg by a cylindrical tool. Unlike the delivery tool in animals, the device used during plant sex consists of a single cell, and only two sperm cells are discharged during each delivery event,” explained Professor Anja Geitmann of the university’s Department of biology. “Our findings offer new insight into how life evolved on Earth and are significant with regards to human health, as a traffic jam on these highways that also exist in human cells can cause cancer and illnesses such as Alzheimer’s.” (more…)
When a batch of bright cosmic objects first appeared in maps in 2008 made with data from the South Pole Telescope, astronomers at the University of Chicago’s Kavli Institute for Cosmological Physics regarded it only as an unavoidable nuisance.
The light sources interfered with efforts to measure more precisely the cosmic microwave background—the afterglow of the big bang. But the astronomers soon realized that they had made a rare find in South Pole Telescope’s large survey of the sky. The spectra of some of the bright objects, which is the rainbow of light they emit, were inconsistent with what astronomers expected from the well-known population of radio galaxies. (more…)
Comet 2013 A1 (Siding Spring) will make a very close approach to Mars in October 2014.
The latest trajectory of comet 2013 A1 (Siding Spring) generated by the Near-Earth Object Program Office at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., indicates the comet will pass within 186,000 miles (300,000 kilometers) of Mars and there is a strong possibility that it might pass much closer. The NEO Program Office’s current estimate based on observations through March 1, 2013, has it passing about 31,000 miles (50,000 kilometers) from the Red Planet’s surface. That distance is about two-and-a-half times that of the orbit of outermost moon, Deimos.
Scientists generated the trajectory for comet Siding Spring based on the data obtained by observations since October 2012. Further refinement to its orbit is expected as more observational data is obtained. At present, Mars lies within the range of possible paths for the comet and the possibility of an impact cannot be excluded. However, since the impact probability is currently less than one in 600, future observations are expected to provide data that will completely rule out a Mars impact. (more…)
