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Comet

Giant comets and mass extinctions of life: Looking at the crater record


Comment: The full paper can be viewed here.


Abstract
I find evidence for clustering in age of well-dated impact craters over the last 500 Myr. At least nine impact episodes are identified, with durations whose upper limits are set by the dating accuracy of the craters. Their amplitudes and frequency are inconsistent with an origin in asteroid breakups or Oort cloud disturbances, but are consistent with the arrival and disintegration in near-Earth orbits of rare, giant comets, mainly in transit from the Centaur population into the Jupiter family and Encke regions. About 1 in 10 Centaurs in Chiron-like orbits enter Earth-crossing epochs, usually repeatedly, each such epoch being generally of a few thousand years' duration. On time-scales of geological interest, debris from their breakup may increase the mass of the near-Earth interplanetary environment by two or three orders of magnitude, yielding repeated episodes of bombardment and stratospheric dusting. I find a strong correlation between these bombardment episodes and major biostratigraphic and geological boundaries, and propose that episodes of extinction are most effectively driven by prolonged encounters with meteoroid streams during bombardment episodes. Possible mechanisms are discussed.

Comment: As Napier writes in his conclusion, "positive evidence for such [bombardment] episodes appears in the impact cratering record. They are found to be tightly correlated with substantial marine extinctions at the level of genera. ... it is suggested here that prolonged atmospheric perturbations arising from fireball storms and dusting are the most energy-efficient means of collapsing food chains, yielding both marine and land extinctions."

See also: Track this: Unseen 'dark comets' may pose threat to Earth


Saturn

Further evidence of Solar System-wide 'Climate Change': A "curious abundance" of methane detected spewing from Saturn's icy moon Enceladus

© Southwest Research Institute
Illustration depicts the potential origins of methane found in the plumes of the Saturn moon, Enceladus. Scientists believe the plumes originate from an internal liquid-water ocean in the south polar region.
NASA's Cassini spacecraft has measured a curious abundance of methane spewing into the atmosphere of Saturn's icy moon Enceladus. A team of American and French scientists published findings in Geophysical Research Letters suggesting two scenarios that could explain the methane abundance observed in the plumes.

In 2005 Cassini's magnetometer and imaging data revealed the surprising existence of geysers in the south polar region ejecting water vapor into space. Scientists now believe that Enceladus harbors an internal liquid-water ocean under tons of icy crust, and that the plumes originate there. Analyzing the composition of the plumes, therefore, can provide a direct window to what is happening in the inner ocean. Cassini has since flown through the plumes, allowing scientists to determine that these watery geysers contain other volatile species, including hydrogen, carbon dioxide, ammonia, and methane. Volatiles are chemical elements and compounds with low boiling points that are associated with a planet's or moon's crust or atmosphere.

"We modeled what would happen to those species in a subsurface ocean in Enceladus," said the paper's lead author Alexis Bouquet, a French graduate student at the University of Texas at San Antonio. "With high pressures expected in a subsurface ocean, clathrates could form and deplete the ocean of volatiles."

Comment: So now we have a "curious abundance" of methane spewing into the atmosphere of Saturn's icy moon Enceladus. Only a few months ago we had 'methane outgassing on Mars'.

There has been increased methane outgassing here on Earth too recently:

Arctic Ocean leaking methane faster than anticipated
Vast methane plumes discovered escaping from Arctic seafloor north of Siberia
New climate change threat: Arctic seabed releases millions of tons of methane into atmosphere

As well as "increasingly stormy" conditions on Uranus, last year we saw increased volcanic activity on Jupiters moon Io, scientists have been puzzled by the wobble of Saturn's moon Mimas and a major increase in asteroid activity has seen MIT astronomers upgrade the solar system from stable to dynamic

What is causing these recent solar system-wide 'climate changes'?

Could it be part of an overall 'grounding' of our solar system, caused perhaps by the close approach of the system's Twin Sun? Clearly something BIG is producing systemic effects, rather than isolated effects on individual planets.


Info

'Underground' ocean confirmed on Jupiter's largest moon

© NASA, ESA, G.Bacon (StScl)
An artist's impression of aurora on Ganymede.
Scientists using the Hubble Space Telescope have confirmed that the Jupiter-orbiting moon Ganymede has an ocean beneath its icy surface.

The finding resolves a mystery about the largest moon in the solar system after NASA's now-defunct Galileo spacecraft provided hints that Ganymede has a sub-surface ocean during exploration of Jupiter and its moons from 1995 to 2003.

Scientists say it took some detective work to confirm the discovery.

Like Earth, Ganymede has a liquid iron core that generates a magnetic field, though Ganymede's field is embedded within Jupiter's magnetic field. That sets up an interesting dynamic with telltale visuals -- twin bands of glowing aurora around Ganymede's northern and southern polar regions.

As Jupiter rotates, its magnetic field shifts, causing Ganymede's aurora to rock. Scientists measured the motion and found it fell short. Using computer models, they realised that a salty, electrically conductive ocean beneath the moon's surface was counteracting Jupiter's magnetic pull.

"Jupiter is like a lighthouse whose magnetic field changes with the rotation of the lighthouse. It influences the aurora," says geophysicist Joachim Saur, with the University of Cologne in Germany.

"With the ocean, the rocking is significantly reduced," says Saur.

Scientists ran more than 100 computer models to see if anything else could be having an impact on Ganymede's aurora. They also repeated the seven-hour, ultraviolet Hubble observations and analysed data for both belts of aurora.

"This gives us confidence in the measurement," says Saur.

TV

12 top Russian inventions that changed the world

Russian inventors have contributed generously to the development of global scientific thought. Many of their inventions have literally transformed the world, enabling us to enjoy such blessings of civilisation as aircraft, cars, computers and television. RIR presents a dozen of such revolutionary innovations that have become an integral part of modern existence.

Caterpillar tracks, track assembly

In 1837, Russian army captain Dmitry Zagryazhsky came up with drawings of a caterpillar drive and applied to the Ministry of Finance for a patent for his invention of a "carriage with a flat chain mechanical caterpillar". He was granted a patent but his invention did not interest manufacturers at that time and the patent was annulled in 1839. Much later, in 1877, Russian peasant and self-taught inventor Fyodor Blinov completed Zagryazhsky's unfinshed task and created a wagon that moved on caterpillars. This invention gave the green light to production of tractors and, subsequently, of tanks.

Image
© ITAR-TASS

Comment: Take note of the time period when most of these ideas or inventions were developed: late imperial Russia.


Eye 1

New procedure may turn brown eyes blue

© Thinkstock
A new technique may be able to turn brown eyes blue. But is it safe?
The idea to use lasers to turn brown eyes blue was born in an unlikely place: a dermatologist's office.

Driving home after having some pigment spots removed from his skin by laser, Gregg Homer wondered what would happen if you used a similar laser on the eyes.

An inventor who had a Ph.D in biology, Homer did a little research and quickly realized the potential of the idea: a study in the 1980's had shown that underneath every brown eye is a blue eye. And that brown layer, Homer discovered, appeared to be superficial enough that it could, theoretically, be removed.

"I went back to my dermatologist and said, I've got a question for you," Homer told Discovery News. "What would happen if you used this on an iris?"

The dermatologist eventually joined his board of investigators, and now, almost 20 years later, the surgery is going through human testing in Costa Rica via Homer's company called Stroma.

The original idea, that the frequency of the green laser is such that it passes straight through the cornea and is only absorbed by dark color, makes it "incredibly safe and incredibly differentiating," Homer said.

The change isn't immediate; the laser is set at a low energy so that the blue eye is revealed over a couple of weeks.

While there have been no adverse effects in the 37 people who have had one eye treated in trials outside of the U.S., Homer said, it's too early to say for certain what long-term effects the procedure could have. Ophthalmologists say the primary health concern, at least theoretically, is glaucoma.

Bulb

Attention decay in science: Study reveals there are too many studies

Image
© Reuters/Paul Hackett
Though one might assume an ever-increasing torrent of studies promotes knowledge, it actually seems to have the opposite effect. US and Finnish researchers have found that science could be in decay, as scholars can't keep pace with scientific literature.

It took an entire study to find that the number of studies exceeds the ability of scientists to digest published literature. The research, dubbed 'Attention decay in science,' was recently published online by professors from universities in Finland and California.

The "thorough study of the life-cycle of papers in different disciplines" - clinical medicine, molecular biology, chemistry, and physics - stresses that new studies are simply "stealing" the attention of scholars, so the life-cycles of papers has dropped since the 1960s.

"The exponential growth in the number of scientific papers makes it increasingly difficult for researchers to keep track of all the publications relevant to their work," the authors wrote in the study. "Consequently, the attention that can be devoted to individual papers, measured by their citation counts, is bound to decay rapidly."

Scientists have previously warned about the effects that the digital age, including the exponential growth of information, is having on culture and the human mind. However, this is the first indication that the sufferings of science are the same.

Comment: Too much information for scientists to keep up with is just another way of suppressing and controlling knowledge.

See also:

The Corruption of Science in America


Magnify

Climate change may produce human mutations

© Thinkstock
Climate change may produce human mutations that lead to higher rates of disease but may also have the potential for making mutants that are superior to the present human population. John H. Wilson with the Department of Molecular and Human Genetics at Baylor College of Medicine in Houston, Texas identified the genes and the climate stresses that are most likely to change under climate change. The discovery was reported in the March 9, 2015, edition of the journal Proceedings of the National Academy of Sciences.

Wilson and colleagues found that extremes of heat, extremes of cold, oxygen deprivation, and oxidative stress all produce higher rates of mutation in the regions of human DNA that are most prone to mutation. Climate stresses have a unique pathway to produce mutations that involve the stimulation of DNA rereplication. The researchers found that limiting the availability of replication origin-licensing factor CDT1 reduced the rate of mutation.


Comment: There certainly is climate 'change'. The global 'warming' hoax is being exposed and more scientists are warning of global 'cooling'.


Comment: Mutations may also be triggered by some form of electrophonic phenomena, some incidents of which may be identified as 'strange sounds' and linked to the increasing number of fireball / meteors we have witnessed in recent years. This is explained in Pierre Lescaudron's book, Earth Changes and the Human-Cosmic Connection. Citing Z. K. Silagadze in his publication 'Tunguska genetic anomaly and electrophonic meteors':
Some genetic anomalies were reported in the plants, insects and people of the Tunguska region. Remarkably, the increased rate of biological mutations was found not only within the epicenter area, but also along the trajectory of the Tunguska Space Body (TSB). At that no traces of radioactivity were found, which could be reliably associated with the Tunguska event.
See also: Comets and the Horns of Moses - Chapter 4: Legends of the Fall and Genetic Mutations


Cards

Gambler's fallacy: Bias at the neuronal level

It's called the gambler's fallacy: After a long streak of losses, you feel you are going to win. But in reality, your odds of winning are no different than they were before.

For years, the gambler's fallacy has been thought to be a prime example of human irrationality, but a new study published by researchers from the Texas A&M Health Science Center suggests that our brains naturally soak up the strange statistics of random sequences, causing us to commit the gambler's fallacy.

The study, which appears in the March 9 issue of theProceedings of the National Academy of Sciences, was designed to help understand the gambler's fallacy at the neural level. Researchers took a computer model of biological neurons and trained it with random sequences. They found that by simply observing a coin being tossed repeatedly, the neurons could learn to differentiate and react to different patterns of heads and tails. Most interestingly, the neurons that preferred alternating patterns such as head-tail significantly outnumbered the neurons that preferred repeating patterns such as head-head.

"In other words, these neurons behaved just like the gamblers in a casino: when the outcome of a fair coin toss is a head, they are more likely to predict that the following toss will be a tail than to predict it will be a head, despite the fact that either pattern is equally probable," said principal investigator Yanlong Sun, Ph.D., an assistant professor of microbial pathogenesis and immunology at the Texas A&M Health Science Center College of Medicine.

Arrow Up

Photos offer first-ever evidence of male tigers as family men

© Wildlife Conservation Society
Photo composite of images showing Amur tiger family, led by adult male, as they walk past camera trap over a period of two minutes..
Male Amur tigers are generally thought to live a solitary existence; however, a new series of photographs released by the Wildlife Conservation Society has revealed a family of wild Amur tigers with an adult male with family.

The photos are from a camera trap slideshow and they reveal the "tiger dad" passing through a Russian forest along with an adult female and three cubs. Researchers note this is the first observation this kind of social behavior. The WCS also released a photo composite of a sequence of images showing the whole family as they wandered past the camera trap over the course of two minutes.

"Although WCS's George Schaller documented sporadic familial groups of Bengal tigers as early as the 1960s, this is the first time such behavior has been photographed for Amur tigers in the wild," said Dale Miquelle, the director of WCS Russia. "These photos provide a small vignette of social interactions of Amur tigers, and provide an evocative snapshot of life in the wild for these magnificent animals."

Cassiopaea

Milky Way may be 50 per cent bigger than thought

© A. Fitzsimmons/ESO
Home extension: an extra ring-like filament could expand the size of our galaxy by 50 per cent.
A ring-like filament of stars wrapping around the Milky Way may actually belong to the galaxy itself, rippling above and below the relatively flat galactic plane. If so, that would expand the size of the known galaxy by 50 percent and raise intriguing questions about what caused the waves of stars.

Scientists used data collected by the Sloan Digital Sky Survey to reanalyze the brightness and distance of stars at the edge of the galaxy. They found that the fringe of the disk is puckered into ridges and grooves of stars, like corrugated cardboard.

"It looks to me like maybe these patterns are following the spiral structure of the Milky Way, so they may be related," astronomer Heidi Newberg, with Rensselaer Polytechnic Institute in New York, told Discovery News.

She and colleagues suspect that a dwarf galaxy may have plunged through the disk of the Milky Way, setting off ripples, like a pebble falling into a pond.

Intruder galaxies also may have set up spiral wave patterns that later trigger star formation in the gas along waves, leading to spiral arms in galaxies.