Category: Earth

Dark matter is darker than we thought


Click to enlarge

This panel of images represents a study of 72 colliding galaxy clusters conducted by a team of astronomers using NASA’s Chandra X-ray Observatory and Hubble Space Telescope. The research sets new limits on how dark matter – the mysterious substance that makes up most of the matter in the Universe – interacts with itself…

RTFA – more research in progress. I wonder if we’ll sort out dark matter in what remains of my lifetime?

Paleoindians in the American Southwest and Northern Mexico

El Fin del Mundo
El Fin del MundoHenry Wallace

Paleoindian research encompasses a number of broad questions of far-reaching significance. Who were the first peoples to reach the Americas? When did they arrive? What was the relationship between the makers of Clovis spear points and the extinction of megafauna, such as the horse, mammoth, dire wolf, and other animals? Although these issues have long been debated, no consensus has been achieved. Big questions can persist because of in- sufficient evidence or because re- searchers have not adequately or fully interpreted the available infor- mation. A few researchers have pro- posed dramatically new ideas— such as the possibility of a comet col- liding with the earth (page 18)— and others, like Joe Cramer, have decided that these questions will be resolved only by supporting many more researchers who will generate new data. Both approaches are ex- amined in this issue of Archaeology Southwest…

“The end of the last Ice Age in North America was a time of enormous change: mile-thick glaciers were retreating rapidly, the sea level was rising, and large mammals, such as mammoths, ground sloths, camels and dire wolves would soon disappear.” Although a convergence of climate change and Paleo-Indian hunters may be a cause of the great extinction, “researchers still do not know exactly what happened.”

My own vulgate opinion is not much better informed than the average American science buff – excepting the portion of that opinion formed during the comparatively brief time I lived in the Navajo Nation plus day-to-day experience working construction trades in northern New Mexico, sometimes within one or another Rio Grande or Northern Pueblo.

I agree with that school of thought that presumes Paleoindian hunters to be the primary cause of the great extinction of large mammals from North America. Not unusual when and where human beings are part of the equation. Regardless – RTFA. It is a lovely, in-depth examination of many of the questions of the Paleoindian period in North American history.

Meanwhile…

“…meanwhile…” is a short film created during the “Porgrave” shooting, the latest film by Sandro Bocci, that will be released in late 2015. Bocci adds…

This is an infinitesimal part of the wonderful world in which we live and of which we should take better care. A trip through a different perspective that would encourage reflection on the consequences of our actions on each scale of space and time. Enjoy the vision

Delightful underwater timelapse photography.

Thanks, Ursarodinia

One step closer to artificial photosynthesis

Caltech scientists, inspired by a chemical process found in leaves, have developed an electrically conductive film that could help pave the way for devices capable of harnessing sunlight to split water into hydrogen fuel.

When applied to semiconducting materials such as silicon, the nickel oxide film prevents rust buildup and facilitates an important chemical process in the solar-driven production of fuels such as methane or hydrogen…

The development could help lead to safe, efficient artificial photosynthetic systems — also called solar-fuel generators or “artificial leaves” — that replicate the natural process of photosynthesis that plants use to convert sunlight, water, and carbon dioxide into oxygen and fuel in the form of carbohydrates, or sugars…

The team has shown that its nickel oxide film is compatible with many different kinds of semiconductor materials, including silicon, indium phosphide, and cadmium telluride. When applied to photoanodes, the nickel oxide film far exceeded the performance of other similar films—including one that Lewis’s group created just last year. That film was more complicated…

Lewis cautions that scientists are still a long way off from developing a commercial product that can convert sunlight into fuel. Other components of the system, such as the photocathode, will also need to be perfected.

Still, it’s a helluva big step. There is no more economical power source than the sun available to this planet and populations – once we figure out how to transform it more and more affordably into electricity.

Abundant water on Jupiter’s moon, Ganymede – underground


Click to enlargeNASA/JPL

Astronomers have found the most conclusive evidence yet that a large watery ocean lies beneath the surface of Jupiter’s moon Ganymede…With the discovery, Ganymede joins Enceladus and Europa as another moon in the solar system with a confirmed subterranean ocean.

“The solar system is now looking like a pretty soggy place,” said Jim Green, director of planetary science at NASA. “The more we look at individual moons, the more we see that water is really in enormous abundance.”

And where there’s water, there’s a chance of life.

Scientists have suspected for decades that a subterranean ocean might slosh between the rocky mantle and icy crust of Ganymede, the largest moon in our solar system, but they had not been able to prove it definitively until now.

Using the Hubble Telescope, a team of researchers has detected slight fluctuations in two bands of glowing aurorae in Ganymede’s atmosphere that they say could occur only if the moon contained a salty body of water…

Saur figured that…regular shifts in Jupiter’s magnetic field would affect the position of the aurorae in Ganymede’s atmosphere differently depending on whether or not the moon has a subsurface ocean.

Computer models show that if Ganymede did not have a subsurface ocean, the changes in Jupiter’s magnetic field should cause the bands of hot, electrically charged gas to rock six degrees over a 10-hour period. However, if the moon contained a salty ocean, it would reduce the rocking of the auroras to just two degrees.

The reason for the difference is that a saltwater ocean is electrically conductive and creates a secondary magnetic field that would suppress the effects of Jupiter’s magnetic field.

Saur looked at measurements taken by the Hubble Telescope in 2010 and 2011 of auroras over both the north and south poles of Ganymede and saw that the auroras only moved two degrees over a seven-hour period…

As astronomers continue their search for life elsewhere, this technique could help them to identify what other bodies might harbor water and, perhaps, life forms beyond Earth.

Interesting stuff. Yes, I’d love to be in on the trip to Ganymede for a walkabout. See if we can find some subsurface beachfront property.

Mass deaths in the Americas signaled start of the Anthropocene Epoch

The atmosphere recorded the mass death, slavery and warfare that followed 1492. The death by smallpox and warfare of an estimated 50 million native Americans—as well as the enslavement of Africans to work in the newly depopulated Americas—allowed forests to grow in former farmland. By 1610, the growth of all those trees had sucked enough carbon dioxide out of the sky to cause a drop of at least seven parts per million in atmospheric concentrations of the most prominent greenhouse gas and start a little ice age. Based on that dramatic shift, 1610 should be considered the start date of a new, proposed geologic epoch — the Anthropocene, or recent age of humanity — according to the authors of a new study…

Simon Lewis and Mark Maslin, a geologist at UCL, dub the decrease in atmospheric carbon dioxide the “Orbis spike,” from the Latin for world, because after 1492 human civilization has progressively globalized. They make the case that human impacts on the planet have been dramatic enough to warrant formal recognition of the Anthropocene epoch and that the Orbis spike should serve as the marker of the start of this new epoch in a paper published in Nature on March 12…

The Anthropocene is not a new idea. As far back as the 18th century, the first scientific attempt to lay out a chronology of Earth’s geologic history ended with a human epoch. By the 19th century, the idea was commonplace, appearing as the Anthropozoic (“human life rocks”) or the “Era of Man” in geology textbooks. But by the middle of the 20th century, the idea of the Holocene—a word which means “entirely recent” in Greek and designates the most recent period in which the great glacial ice sheets receded — had come to dominate, and incorporated the idea of humans as an important element of the current epoch but not the defining one.

That idea is no longer sufficient, according to scientists ranging from geologists to climatologists. Human impacts have simply grown too large, whether it’s the flood of nitrogen released into the world by the invention of the so-called Haber-Bosch process for wresting the vital nutrient from the air or the fact that civilization now moves more earth and stone than all the world’s rivers put together…

The CO2 drop coincides with what climatologists call the Little Ice Age. That cooling event may have been tied to regenerated forests and other plants growing on some 50 million hectares of land abandoned by humans after the mass death brought on by disease and warfare, Lewis and Maslin suggest. And it wasn’t just the death of millions of Americans, as many as three-quarters of the entire population of two continents. The enslavement (or death) of as many as 28 million Africans for labor in the new lands also may have added to the climate impact. The population of the regions of northwestern Africa most affected by the slave trade did not begin to recover until the end of the 19th century. In other words, from 1600 to 1900 or so swathes of that region may have been regrowing forest, enough to draw down CO2, just like the regrowth of the Amazon and the great North American woods, though this hypothesis remains in some dispute…

The changes wrought by humans over the course of the last several centuries, if not longer, will echo in the future, whether in the form of transplanted species, like earthworms or cats, crop pollen in lake sediments or even entire fossilized cities. Still, whether the Anthropocene started tens, hundreds or thousands of years ago, it accounts for a minute fraction of Earth’s history. And this new epoch could end quickly or endure through millennia, depending on the choices our species makes now. “Embracing the Anthropocene reverses 500 years of scientific discoveries that have made humans more and more insignificant,” Maslin notes. “We argue that Homo sapiens are central to the future of the only place where life is known to exist.”

Lewis and Maslin are scientists and, as such, have submitted their study for peer review. From the viewpoint of a lifetime student of science this sounds pretty reasonable. I look forward to reading some of the discussion to see where it all leads. Unless you, too, do that – this will be nothing more than a passing footnote to the overwhelming body of climate science thoroughly vetted and endorsed by the science community worldwide – and completely ignored except to revile as a commie plot by the ignoranuses inhabiting Congress and staffing the Koch Bros Legions.

American mass media being what it is – the only ongoing journalistic interest will come from that narrow band of the American Left that inhabits the danger zone beyond The Beltway and network/cable TV safety net. Perhaps, some time in the vaguely distant future when science is considered – along with civics – a source of enlightenment for Americans, the term will be allowed in public.