Tiny lab versions of 12-foot tall snow spikes that form naturally on some high mountain glaciers may someday help scientists mitigate the effects of global warming in the Andes, according to a University of Colorado at Boulder professor.
CU-Boulder physics Assistant Professor Meredith Betterton said the spikes, known as penitentes, are shaped when concentrated rays of sunlight evaporate snow from low spots on glacier fields in a process known as sublimation. The lab studies confirm that the low spots, or troughs, deepen as intense sunlight strikes them, sculpting penitentes by the hundreds of thousands on some glaciers, she said.
Some scientists have predicted that penitentes might help put the brakes on shrinking glaciers in a warming climate by blocking sunlight that might otherwise be absorbed by glacial surfaces, said Betterton. She gave a presentation on penitentes at the March Meeting of the American Physical Society in Denver March 5-9, which hosted more than 7,000 scientists.
Science & Technology
Scientists and engineers remain on course in their efforts to determine what caused the twin Pioneer spacecraft to apparently drift off course by hundreds of thousands of kilometres during their three-decade missions. Within a year, they expect to be able to decide whether this drift was caused by a fault on the spacecraft.
Launched 35 years ago on Friday, Pioneer 10 was the first spacecraft to reach the outer solar system and return pictures of Jupiter. It was followed by Pioneer 11, which launched on 5 April 1973 and also visited Saturn.
After these historic encounters, NASA kept track of the drifting spacecraft, finally losing contact with Pioneer 11 in 1995 and Pioneer 10 in 2003.
Launched 35 years ago on Friday, Pioneer 10 was the first spacecraft to reach the outer solar system and return pictures of Jupiter. It was followed by Pioneer 11, which launched on 5 April 1973 and also visited Saturn.
After these historic encounters, NASA kept track of the drifting spacecraft, finally losing contact with Pioneer 11 in 1995 and Pioneer 10 in 2003.
When humans first trekked from Asia to North America, perhaps as long as 25,000 years ago, the continent was gripped by ice sheets and glaciers. Those hardy immigrants probably traveled by boat or along the shore, where finding food and shelter would have been easier. The trouble for archaeologists is that as the ice melted, the seas rose and covered any traces of this early migration. Now marine geologists and archaeologists are hunting for underwater clues in the Gulf of Mexico.
This morning, a research expedition steamed out of the Port of Galveston, Texas, for the Flower Garden Banks National Marine Sanctuary, about 180 kilometers off the coast of Texas and Louisiana. Led by Robert Ballard, president of the Institute for Exploration at Mystic Aquarium in Mystic, Connecticut, and Kevin McBride of the Mashantucket Pequot Museum and Research Center in Connecticut, the expedition consists of a 44-meter-long Navy research submarine, two ships, and a remotely operated vehicle (ROV).
This morning, a research expedition steamed out of the Port of Galveston, Texas, for the Flower Garden Banks National Marine Sanctuary, about 180 kilometers off the coast of Texas and Louisiana. Led by Robert Ballard, president of the Institute for Exploration at Mystic Aquarium in Mystic, Connecticut, and Kevin McBride of the Mashantucket Pequot Museum and Research Center in Connecticut, the expedition consists of a 44-meter-long Navy research submarine, two ships, and a remotely operated vehicle (ROV).
Physicists analyzing data taken by the HyperCP experiment at Fermilab in the US claim they may have glimpsed the first Higgs boson -- the particle many think is responsible for all mass in the universe. However, for their claim to be correct our current 30-year-old Standard Model of particle physics would have to be set aside in favour of an alternative "supersymmetric" model.
The great triumph of the Standard Model is that it unites two of the fundamental forces - the weak and electromagnetic force - into a single, symmetric "electroweak" force at high energies. But at low energies, a symmetric electroweak theory would imply that particles have no mass, which is clearly wrong.
The great triumph of the Standard Model is that it unites two of the fundamental forces - the weak and electromagnetic force - into a single, symmetric "electroweak" force at high energies. But at low energies, a symmetric electroweak theory would imply that particles have no mass, which is clearly wrong.
A new study is raising questions about whether a suspect fingered by scientists is as big a driver of human aging as previously thought. For years, researchers believed that small DNA mutations in the energy-producing parts of our cells lead us down the road to aching bodies and wrinkled skin. But mice engineered to have hundreds of times more of these mutations than average showed no signs of premature aging, indicating that scientists are going to have to look elsewhere for their culprit.
Cells contain thousands of tiny structures called mitochondria, which generate energy and harbor their own DNA distinct from the cell's nucleus. Scientists suspect this DNA, called mitochondrial DNA, or mtDNA, may be more vulnerable to mutations from errors in DNA replication. Over the last five years, several studies in mice pointed to a link between these mutations in mtDNA and the decline of tissue function that occurs as humans and animals age.
Cells contain thousands of tiny structures called mitochondria, which generate energy and harbor their own DNA distinct from the cell's nucleus. Scientists suspect this DNA, called mitochondrial DNA, or mtDNA, may be more vulnerable to mutations from errors in DNA replication. Over the last five years, several studies in mice pointed to a link between these mutations in mtDNA and the decline of tissue function that occurs as humans and animals age.
Scientists have delivered proof of what many have suspected for years - the weather is always worse at weekends.
Saturdays are colder and wetter than any other day, a major study of weather patterns has revealed.
And the researchers insist people themselves are to blame for the trend - because they drive more during the week and increase dust pollution.
Meteorologists looked at 6.3million pieces of climate data from across Europe between 1991 and 2005.
It's thought to be the most comprehensive weather study ever.
They found Wednesdays have the highest average temperatures and Mondays are the driest. Saturdays were worst on both counts.
Saturdays are colder and wetter than any other day, a major study of weather patterns has revealed.
And the researchers insist people themselves are to blame for the trend - because they drive more during the week and increase dust pollution.
Meteorologists looked at 6.3million pieces of climate data from across Europe between 1991 and 2005.
It's thought to be the most comprehensive weather study ever.
They found Wednesdays have the highest average temperatures and Mondays are the driest. Saturdays were worst on both counts.
Japan's advanced humanoids can now serve tea and wash the cup afterwards, but they still need to learn from their mistakes if they are to become real household helpers. A Tokyo University team this week showed their latest robots which can perform more complicated daily tasks, but the machines still have a learning curve.
Chinese scientists succeeded to attach a chip to the brain of a pigeon which allowed them to remotely control the pigeon movements. The scientists from the Robot Engineering Technology Research Centre at Shandong University of Science and Technology in China used hair-thin electrodes which were implanted in the brain of the pigeon in key locations responsible for movement.
The Chinese scientists already successfully implanted similar electrodes in fish, rats, mice and monkeys in research that was driven by military and intelligence interests. This is the first time a bird is being controlled in this way. The scientists reported that they successfully ordered the birds to fly right or left or up or down using a computer and remote control.
The US navy also hopes to use similar implants to exploit sharks' ability to sense minute electrical changes left by a vessel as it sail in the vicinity of the shark. IN this way the navy will have a highly sensitive biological sensor which will be very hard for the enemy to detect.
The Chinese scientists already successfully implanted similar electrodes in fish, rats, mice and monkeys in research that was driven by military and intelligence interests. This is the first time a bird is being controlled in this way. The scientists reported that they successfully ordered the birds to fly right or left or up or down using a computer and remote control.
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The US navy also hopes to use similar implants to exploit sharks' ability to sense minute electrical changes left by a vessel as it sail in the vicinity of the shark. IN this way the navy will have a highly sensitive biological sensor which will be very hard for the enemy to detect.
Astronomers are watching a galaxy rip to shreds, a finding that could help reveal how galaxies go from stellar riches to rags.
While looking at the galaxy cluster Abell 2667 with the Hubble Space Telescope, scientists found a spiral galaxy which they nicknamed the "Comet Galaxy."
The gas and stars of the Comet Galaxy-moving through the cluster at speeds of more than 2 million mph-are being stripped away by the tidal forces of the cluster. Also, the pressure of the cluster's scorching gas plasma - known as ram pressure stripping - is adding to the damage.
While looking at the galaxy cluster Abell 2667 with the Hubble Space Telescope, scientists found a spiral galaxy which they nicknamed the "Comet Galaxy."
The gas and stars of the Comet Galaxy-moving through the cluster at speeds of more than 2 million mph-are being stripped away by the tidal forces of the cluster. Also, the pressure of the cluster's scorching gas plasma - known as ram pressure stripping - is adding to the damage.
Physicists in the US have got to grips with a phenomenon that can cause hurricane winds to intensify rapidly. So-called "eyewall replacement" occurs when the cloud wall encircling the eye of a major hurricane breaks down, only to be replaced by a new wall farther out. The physicists claim that this latest insight will help to predict when and to what extent hurricanes will intensify
The dynamics that govern a hurricane's path and intensity are incredibly complex, and one of the least understood is eyewall replacement. In this process the wind speed drops initially when the first cloud walls collapse. But the new walls that move in to replace them re-intensify the wind as they shrink inward - a similar result of angular momentum conservation that makes ice skaters spin faster as they fold their arms.
The dynamics that govern a hurricane's path and intensity are incredibly complex, and one of the least understood is eyewall replacement. In this process the wind speed drops initially when the first cloud walls collapse. But the new walls that move in to replace them re-intensify the wind as they shrink inward - a similar result of angular momentum conservation that makes ice skaters spin faster as they fold their arms.
Comment: While Japan's humanoids are busy learning to serve tea and crumpets, ours are facing much more difficult problems: