Jul 18, 2015

Pluto's Weirdly Young Surface Doesn't Make Sense

Scientists with NASA’s New Horizons mission are puzzling over how a world that never gets more sun than Earth at twilight is reshaping its surface, filling in craters, cracking its crust and building towering mountains and smooth hills.

With just 1 percent of the 50 gigabytes of data collected during New Horizons’ approach and close encounter with Pluto back on the ground, scientists already are rethinking long-held ideas about icy bodies in the outer reaches of the solar system.

Pluto, for example, appears far from a pristine remnant left over from the formation of the solar system some 4.6 billion years ago. Its surface is brimming with evidence of relatively current, and possibly ongoing, geological processes.

New Horizons was dispatched to study Pluto and other icy bodies in the Kuiper Belt, located beyond Neptune’s orbit.

Pluto, and to some extent its big moon Charon, have young and varied terrains, New Horizons found.

“The landscape is just astoundingly amazing,” New Horizons scientist Jeffrey Moore, with NASA’s Ames Research Center in Moffett Field, Calif., told reporters on a conference call.

A second batch of pictures released on Friday shows that part of Pluto’s bright, heart-shaped region (since named “Tombaugh Regio” for Pluto’s discoverer Clyde Tombaugh) contains a vast, crater-free plain, estimated to be less than 100 million years old.

Resembling frozen mud cracks on Earth, the region, nicknamed “Sputnik Planum” is broken into irregular shaped polygons, roughly 12- to 20 miles in diameter, that are boarded by what appear to be shallow troughs.

“Those could be only a week old, for all we know,” Moore said.

The polygons could have been formed by convection, patterns etched in Pluto’s surface ice like the roiling surface of a pot of boiling oatmeal. What drives the process, however, has yet to be determined.

The polygons also could be like mud cracks, created by contraction of the surface, Moore added.

Read more at Discovery News

Earth Broke Multiple Warming Records in 2014

As has been seen year after year, the warming of the Earth is causing major changes in many aspects of the planet’s climate, and 2014 was yet another year that showed this trend in stark relief, a report released Thursday says.

Numerous records were broken last year, according to the State of the Climate report, an annual checkup of the global climate published in a special issue of the journal Bulletin of the American Meteorological Society.

Now in its 25th year, the report pulls together hundreds of scientists from dozens of countries to piece together the changes from the previous year in all aspects of the Earth’s climate — from carbon dioxide levels to the planet’s rising temperature, from glacier melt to change in soil moisture — and puts them in the context of decades-long trends.

Here are four key points to draw from the report:

Carbon dioxide levels are rising: This is the trend that underlies global warming, as it is the rise of carbon dioxide and other greenhouse gases from human activities — first recognized in the famous Keeling Curve — that is driving the rise of Earth’s temperature. CO2 levels have been “increasing throughout the recent decades and 2014 was no different,” Deke Arndt of the National Centers for Environmental Information, part of the National Oceanic and Atmospheric Administration, said during a press call.

The global average carbon dioxide level reached a new record high of 397.2 parts per million last year, a nearly 2 ppm rise from 2013 and a 40 percent increase from preindustrial levels. The average for three months of last year — April, May and June — was above 400 ppm; that level will likely be exceeded for many more months this year.

Earth’s temperature is rising: A direct consequence of the build-up of greenhouse gases is a steady rise in Earth’s average temperature from all the excess heat those gases trap and prevent from escaping out into space. Arndt called this temperature rise “one of the most obvious connections to a changing climate.”

Four datasets of global temperatures ranked 2014 as the warmest year on record (or tied for warmest) going back to 1880. A Climate Central analysis showed that 13 of the hottest 15 years on record have all occurred since 2000 and that the odds of that happening randomly without the boost of global warming is 1 in 27 million.

The year was also the warmest on record for particular regions, from California to Europe. A separate Climate Central analysis showed that warming made that record for Europe 35 to 80 times more likely.

Another aspect of the warming trend is the increase in the hottest days and the decrease in the coldest nights, which the new report showed was a trend that continued in 2014.

How the heat content of the upper 2,300 feet of the Earth's oceans differed from the 1993-2014 average.
The oceans are heating up: Not only was Earth’s temperature record warm in 2014, but so were the global oceans, as sea surface temperatures and the heat of the upper oceans also hit record highs. “The heat content is just continuing to pile up,” Greg Johnson, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory, said during the call.

This trend is key because the oceans absorb about 93 percent of all the excess heat trapped by greenhouse gases. “You can kind of think of ocean warming as being global warming,” Johnson said.

The North Pacific in particular was exceptionally hot, and the tropical Pacific moved toward an El Niño state, which features warmer-than-average waters in that region.

All of that heat in the oceans also raised global sea levels to a new record high, more than 2.5 inches above what it was in 1993, as water expands as it heats up.

The oceans are heating up: Not only was Earth’s temperature record warm in 2014, but so were the global oceans, as sea surface temperatures and the heat of the upper oceans also hit record highs. “The heat content is just continuing to pile up,” Greg Johnson, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory, said during the call.

This trend is key because the oceans absorb about 93 percent of all the excess heat trapped by greenhouse gases. “You can kind of think of ocean warming as being global warming,” Johnson said.

The North Pacific in particular was exceptionally hot, and the tropical Pacific moved toward an El Niño state, which features warmer-than-average waters in that region.

All of that heat in the oceans also raised global sea levels to a new record high, more than 2.5 inches above what it was in 1993, as water expands as it heats up.

Overall, ice is melting: All the excess heat in the Earth system, both at the surface and in the oceans, has contributed to the steady disappearance of the planet’s ice, including Arctic sea ice, mountain glaciers and permafrost.

The area of the Arctic Ocean covered by sea ice in September, when the annual minimum occurs, was the sixth lowest extent in the satellite record, going back to 1979. The eight lowest extents in that record have all occurred within the past eight years, the report notes. “So there’s a definite recent decline in sea ice,” Jessica Blunden, a climatologist with ERT, Inc. at NCEI and the lead editor of the report, said.

Added to that is the melt of glaciers around the globe. A survey of three dozen index glaciers showed that 2014 was the 31st consecutive year of overall glacier ice lost. Since 1980, this melt has effectively lopped off 60 feet of ice from the top of each glacier, Blunden said.

Read more at Discovery News

Where Does Water from Snow and Rainfall Actually Go?

Here’s a question that matches the old “If a tree falls in a forest and no one hears it, does it make a sound?” question. But this one is less abstract. If rain or snow falls on land, where does it eventually go?

If your answer is that it turns into runoff that ends up in waterways and eventually flows into the oceans, you’re only partially right. Only about a quarter of the precipitation over land does that. So what happens to the rest?

University of Utah researchers have the answer, and even some precise numbers.

In an article in the journal Science, they report that of the remaining water, most of it — 64 percent — is exhaled back into the atmosphere by plants, in a process called transpiration. Based upon previous studies, another 27 percent lands on leaves and evaporates, and the rest evaporates from soil (6 percent) or from lakes, rivers and streams (3 percent).

The findings actually were a bit of a surprise, because previous research suggested that even more of the water — as much as 80 percent — was accounted for by plant transpiration.

The researchers used hydrogen isotope ratios of water in rain, rivers and the atmosphere from samples and satellite measurements to come up with their numbers.

“It’s important to understand the amount of water that goes through each of these pathways,” one of the study’s authors, University of Utah hydrologist Stephen Good, explained in a press release. “The most important pathway is the water that passes through plants because it is directly related to the productivity of natural and agricultural plants.”

The researchers also found that of the precipitation that seeps down into the Earth’s groundwater, most moves through the soil so quickly that it isn’t available for plants to use. Only 38 percent of the water ends up being involved in moving nutrients, fertilizers or contaminants, or in affecting biological processes.

From Discovery News

Jul 17, 2015

Loch Ness Monster Hunter Hooked on Catfish Theory

A man who has spent 24 years scanning Scotland’s Loch Ness for its legendary mysterious monster reckons Nessie is most likely a giant catfish — although he is not prepared to give up looking just yet.

Steve Feltham, who holds a Guinness World Record for the longest continuous Nessie vigil, says it is the most probable explanation for the enigmatic beast that has captivated people’s imaginations the world over.

“The current frontrunner is the Wels catfish. It’s the most likely explanation,” the 52-year-old told AFP.

“I’m not saying it’s the final explanation. It ticks most of the boxes with sightings — but it doesn’t tick them all.”

Feltham left his home and girlfriend in 1991 to go looking for Nessie and has spent the years since in a caravan on the lake shore, scanning the waters.

Media reports this week suggested Feltham had given up his vigil after favouring the catfish theory, but he insisted he would keep searching for the definitive conclusion.

“We still have this world-class mystery and for the next several decades I hope to carry on trying to find the answer,” he said.

Catfish are native to central and eastern Europe but Feltham believes the Victorians might have introduced them to the deep freshwater lake so they could catch them for sport.

Wels catfish can group up to four meters (13 feet) long and weigh more than 400 kilogrammes (800 pounds) — though they are rarely more than half this size. The scaleless fish can live for at least 30 years.

Sightings dwindling

Feltham concedes there is no record of Wels catfish being released into Loch Ness, Scotland’s largest at 37 kilometers long and over 200 meters deep in some places.

But he said: “Given the number of hunting estates that there are around here, it’s plausible they (the Victorians) may have put a few in, giving themselves some good sport of catching one of the biggest freshwater fish in the world.

“If they did that here in the (late) Victorian era, they would have reached maturity in the 1930s” — the time when the Nessie craze took off.

He said in the early years of his vigil, there would be up to a dozen good sightings per year, but now there might only be one.

“Whatever Nessie turns out to be, it is dwindling. We are looking for the last one or two now,” he said.

Read more at Discovery News

Weakened Solar Activity Could Speed Greenland Ice Melt

Since the Arctic is getting warmer as a result of climate change, you’d expect that Greenland, the immense Danish territory situated on the edge of the Atlantic and Arctic oceans, would be warming too.

Strangely, though, Greenland actually cooled during the 1970s through the 1990s, a time when most of the Northern Hemisphere experienced rising temperatures.

An article just accepted for publication in the journal Geophysical Research Letters, reveals the reason for the seeming inconsistency: The paradoxical effect of solar weather on ocean circulation.

The new study, by a team of Danish, Swiss, American and Japanese researchers, concludes that high solar activity starting in the 1950s and continuing through the 1980s played a role in slowing down ocean circulation between the South Atlantic and the North Atlantic oceans. Combined with an influx of fresh water from melting glaciers, this slowdown halted warm water and air from reaching Greenland and cooled the island.

But that mitigation from global warming didn’t last, and it’s actually reversed itself. Conversely, the researchers’ findings also suggest that weak solar activity, as the sun is currently experiencing, could slowly fire up the ocean circulation mechanism, increasing the amount of warm water and air flowing to Greenland. Starting around 2025, temperatures in Greenland could increase more than anticipated and the island’s ice sheet could melt faster than projected.

This unexpected ice loss would compound projected sea-level rise expected to occur as a result of climate change, Kobashi said. The melting Greenland ice sheet accounted for one-third of the rise in global sea level every year from 1992 to 2011.

“We need to really consider how solar activity will change in the future,” the study’s lead author, University of Bern climate scientist Takuro Kobashi, said in a press release. “If solar activity becomes really low, as scientists expect, the Greenland ice sheet will melt faster than we expected from the climate model with just greenhouse gas (warming).”

Read more at Discovery News

Tobacco Companies Still Battling Smoking-Cancer Link

Do you remember a time way back when the link between smoking and cancer wasn’t clearly established? Anyone who was around at the time is at least 60 years old at this point.

Back in 1964, the Surgeon General released a landmark study that linked tobacco with potentially fatal health risks, such as heart disease and lung cancer. Small-scale studies beginning in the late 1920s suggested a possible connection, and major research efforts were underway by the 1950s, as explained by the American Cancer Society. But the Surgeon General report marked the first time the federal government took a stand on the issue.

Tobacco companies would publish their own findings for decades, employing their own scientists to manufacture a debate. Tobacco use over the years leads to negative, often fatal health consequences. Although often connected to lung cancer, smoking can cause cancer almost anywhere in the body, according to the Centers for Disease Control and Prevention (CDC), including the blood, liver, kidneys, throat and stomach.

Despite billions of dollars paid in settlements, the tobacco industry continues to fight lawsuits against cancer patients who file suit claiming that the companies’ products gave them cancer. These companies also employ a small stable of otolaryngologists — ear, nose and throat doctors — to testify on behalf of the cigarette manufacturers, according to a study released today in the journal Laryngoscope.

The study found that six board-certified otolaryngologists, paid as much as $100,000 for a single case by the tobacco industry, testified in more than 50 cases using scientifically invalid support to back up their opinions. “I was shocked by the degree to which these physicians were willing to testify, in my opinion in an unscientific way, to deny a dying plaintiff — suffering the aftermath of a lifetime of smoking — of a fair trial,” said Robert Jackler of the Stanford University School of Medicine in a statement.

If smoking wasn’t the cause of the plaintiffs’ head and neck cancers in these 50 cases, what did then lead these people to contract these fatal diseases, according to the physicians’ testimonies? The doctors pointed the finger at everything from alcohol to mouthwash to salted fish and more. Doctors and lawyers on behalf of the tobacco companies would pick up on the most minute details of a plaintiff’s lifestyle, even something as simple as living in a city, to create doubt in the minds of jurors.

“An obvious fallacy of this argument lies in the fact that literally billions of nonsmoking people are exposed regularly to gasoline fumes, use cleaning solvents, eat salted fish or live in urban environments,” the journal article explains. “Were these causative factors for head and neck cancer, with even a minute fraction of the potency of tobacco, the rate of head and neck cancer among nonsmokers would be much greater than what has been observed.”

Read more at Discovery News

See Crescent Moon and Venus Team Up This Weekend

On the evening of Saturday (July 18) the crescent moon, as it moves eastward across the sky, will appear to pass directly below the crescent planet Venus, which itself is moving westward across the sky.

Both objects are being lit by the sun in such a way that both appear in our sky as crescents. The moon is just three days past new moon, so only 9 percent of its disk is lit by the sun. The remaining 91 percent is lit by sunlight reflecting off the surface of the Earth, what is called "earthshine"or "earthlight." Sometimes this view is also called "the old moon in the new moon's arms."

To the naked eye, Venus appears like a brilliant pinpoint of light. Turn your binoculars on it, and that slight additional magnification will allow you to see that Venus is also a narrow crescent.

Because Venus is farther away than the moon, it is lit by the sun at a slightly different angle, so is nineteen percent illuminated, a slightly fatter crescent than the moon.

Some observers have suspected a faint glow coming from the part of Venus not in direct sunlight, a phenomenon called "the ashen light."No one knows exactly what causes this glow, but it has been reported by many experienced astronomers. Spectroscopic observations have shown pulses in the light, so it might be due to lightning in the hot acidic atmosphere of Venus.

As mentioned above, even small binoculars provide enough magnification to turn the naked-eye pinpoint of Venus into a visible crescent. This is one of many objects in the sky which are revealed or enhanced in binoculars, which is why they are considered an essential tool for all serious skywatchers.

Binoculars for astronomy should have a front aperture of at least 50 millimeters (2 inches). This is seven times the diameter of the fully dark-adapted eye. Such a small binocular has seven times the resolution and 50 times the light-gathering power of the naked eye.

Read more at Discovery News

Jul 16, 2015

Hong Kong Ivory Trade Called Major Threat to Elephants

Hong Kong’s booming ivory market is helping push elephants toward extinction, conservationists said Thursday, reporting more ivory items on sale there than in any other city.

The sale of ivory items from government-registered stockpiles predating the 1989 ban is legal for domestic use in Hong Kong, but a report by Save the Elephants found tusks from recently slaughtered elephants were being passed off as old ivory, and that this ivory was being bought and then illegally smuggled to mainland China on a huge scale.

“Hong Kong’s ivory trade is creating a significant loophole in international efforts to end the killing of elephants in Africa,” said the report released in Kenya and Hong Kong.

“No other city surveyed has so many pieces of ivory on sale as Hong Kong,” report co-author Esmond Martin said.

The report found more than 30,800 items — mainly jewellery and figurines — for sale in 72 stores and estimated that over 90 percent of sales were to buyers from mainland China, where demand for ivory is high.

Hong Kong’s low taxes make ivory cheaper than on the Chinese mainland.

The report said lax border controls and the sheer volume of people crossing each year abetted the trade, which was having a major impact on efforts to end elephant poaching in Africa.

“A mass slaughtering of African elephants is underway, yet the Hong Kong government is turning a blind eye,” said Alex Hofford of campaign group WildAid.

“For 25 years since the international ban, Hong Kong’s ivory traders appear to have been laundering poached ivory from illegally-killed elephants into their stocks,” said Hofford.

The report described Hong Kong as the world’s third-largest ivory smuggling hub after Kenya and Tanzania.

However, a spokeswoman for Hong Kong’s agriculture, fisheries and conservation department disputed the report and said there was “no plan” to ban the island’s ivory trade.

“There is no evidence showing that Hong Kong’s legal ivory trade contributes to the poaching of elephants in Africa or provides a cover for the laundering of smuggled illegal ivory,” the spokeswoman said.

Call for total ivory retail ban

Multi-tonne seizures of smuggled ivory have been made regularly in recent years.

The ivory comes from poached elephants in countries such as Tanzania, which saw its elephant population drop from 109,000 to 43,000 between 2009 and 2014.

Beijing has made efforts to curb the trade, stepping up prosecutions of smugglers and seizures of ivory at border posts, but campaigners say the measures have not gone far enough.

"Unless the ivory trade in Hong Kong is closed down the territory will continue to represent a major threat to survival of the species," said Iain Douglas-Hamilton, founder of Save the Elephants.

More than 30,000 elephants are killed every year to satisfy demand for ivory in China and the Far East, where tusks fetch more than $2,000 (1,790 euros) a kilogramme.

It is estimated that there are only about 470,000 elephants left in Africa.

"China holds the key to the future of African elephants," said Hamilton. "If the killing continues we will lose most of the elephants in the wild in Africa."

Read more at Discovery News

New Big Feathered Dino Busts Velociraptor Myths

A new elaborately feathered dinosaur is the largest ever discovered to have a well-preserved set of bird-like wings, according to a new study.

The new 5-foot-long dino, Zhenyuanlong suni, not only provides intriguing clues about the evolution of feathers, but it also busts myths about one of its close cousins, Velociraptor, a dinosaur made famous by the Jurassic Park movies.

“Look at Zhenyuanlong and you’re probably seeing, more or less, what a real Velociraptor would have looked like,” senior author Stephen Brusatte told Discovery News.

“Velociraptor would have been a feisty little feathered poodle from hell, not a drab scaly reptilian monster like in the Jurassic Park films,” added Brusatte, who is a paleontologist at the University of Edinburgh’s School of GeoSciences. He co-authored the study, published in the journal Scientific Reports, with paleontologist Junchang Lüof of the Chinese Academy of Geological Sciences.

The scientists came to their conclusions after studying the near-complete and exceptionally well-preserved skeleton for Z. suni, which lived around 125 million years ago in what is now the Liaoning Province of northeastern China. Like Velociraptor, it was a dromaeosaurid -- fast-running, feathered, sickled-clawed dinosaurs that were close relatives of birds.

Z. suni weighed around 25 pounds and, most strikingly, had short, 14-inch-long arms covered with long feathers that looked like quill pens. Today’s eagles and vultures sport a similar type of feather.

This opens up a big question: Could non-avian dinosaurs fly?

Brusatte, Lü and other experts doubt that relatively hefty Z. suni could have flapped itself off the ground.

“Besides the fact that it lacked the large flight muscles and some shoulder adaptations that allow birds to fly, it was simply too heavy,” Alex Dececchi, a researcher at the University of South Dakota, told Discovery News.

Dececchi said it's suspected at least one other non-avian dinosaur, Microraptor, could fly, because it had large wings with feathers that seem to have been suitable for flight.

Z. suni’s feathers, on the other hand, and those of the earliest known feathered dinosaurs, probably were more for form instead of function.

“The first feathers are seen in primitive dinosaurs that clearly lived on the ground and were too big to fly,” Brusatte explained. As for the feathers of Z. suni, “They may have evolved as display structures, gaudy ornaments used to attract mates or to intimidate rivals. Just think about what a peacock does with its tail feathers; it sure isn’t flying with them.”

Michael Habib, an assistant professor at the University of Southern California and a research associate at the Natural History Museum of Los Angeles County, agrees the newly identified dinosaur probably couldn't fly. He did, however, tell Discovery News, “Broad wings with short, relatively weak forelimb bones can still be used to assist with leaping, turning and dropping from otherwise dangerous heights.”

However Z. suni’s feathered wings were used, Habib said that they help to confirm that the evolution of dinosaur/bird wings “was not necessarily tightly coupled to the evolution of flight throughout time. Wings, anatomically speaking, might just be something that many dinosaurs grew as a result of developmental constraints.”

Read more at Discovery News

Oldest Dentistry Found in 14,000-Year-Old Tooth

An infected tooth partially cleaned with flint tools represents the oldest known dentistry, says a new international study on a 14,000-year-old molar.

The find represents the oldest archaeological example of an operative manual intervention on a pathological condition, according to researchers led by Stefano Benazzi, a paleoanthropologist at the University of Bologna.

“It predates any undisputed evidence of dental and cranial surgery, currently represented by dental drillings and cranial trephinations dating back to the Mesolithic-Neolithic period, about 9,000-7,000 years ago, “ Benazzi said.

The patient was a young man, about 25 years old, living in northern Italy.

His well-preserved skeleton was found in 1988 in the Veneto Dolomitesnear Belluno, in a rock shelter burial named Ripari Villabruna.

The find was directly dated between 13,820 and 14,160 years old. It's now kept at the University of Ferrara for further studies.

“The treatment went unnoticed for all these years. The cavity was described as a simple carious lesion,” Benazzi said.

Detailing their finding in the journal Scientific Reports, Benazzi and colleagues show that forms of dental treatment were already adopted in the Late Upper Palaeolithic.

At that time, toothpicks probably made of bone and wood were used to remove food particles between teeth.

However, until now, no evidence had been found to associate Palaeolithic toothpicking with tooth decay.

Beewax dental filling was discovered in a 6,500 year old human tooth from Slovenia, while dental drilling, likely to remove decayed tissue, was discovered in 9,000-year-old molars from a Neolithic graveyard in Pakistan.

Benazzi and colleagues analyzed the lower right third molar of the Villabruna specimen. They noticed the tooth retains a large occlusal cavity with four cavities.Using scanning electron microscopy the researchers uncovered peculiar striations in the internal surface of the large cavity.

“They were the result of a variety of gestures and movements associated with slicing a microlithic point in different directions,” Benazzi said.

Experimental tests carried out on the enamel of three molars using wood, bone and microlithic points confirmed the striations are characteristic of scratching and chipping.

“Basically, the infected tissue was picked away from inside the tooth carefully using a small, sharp stone tool,” Benazzi told Discovery News.

“This shows that Late Upper Paleolithic humans were aware about the deleterious effects of caries, and the need to intervene with an invasive treatment to clean a deep dental cavity,” he added.

The researchers noted the enamel was partially rounded and polished due to wear, indicating the treatment was carried out long before the death of the individual.

The find suggests that dentistry evolved from the much older practice of toothpicking, rather than from drilling procedures.

Read more at Discovery News

Pluto has Ice Mountains, Charon is Active: New Horizons

Little Pluto, smaller than Earth’s moon, has a least one giant mountain range, with water ice the only available building material, scientists with NASA’s New Horizons mission said Wednesday.

The discovery, which popped out from the first of thousands of high-resolution images taken during New Horizons’ close flyby of Pluto and its largest moon Charon on Tuesday, raised immediate questions about how the 11,000-foot (3,350 meters) mountains formed.

“We have no idea at this point,” New Horizons scientist John Spencer, with the Southwest Research Institute in Boulder, Colo., told reporters.

“These mountains are quite spectacular. There may be higher ones elsewhere.”

Scientists believe the mountains are made of water ice, as nitrogen, methane and other materials available on its surface aren't strong enough to support that amount of mass.

“We are seeing the bed ice of Pluto. The water ice is strong enough at Pluto’s temperatures to hold up big mountains, and that’s what we think we are seeing here,” Spencer said.

More details will are expected throughout the week, and especially over the next few months, as New Horizons relays back its images and science observations from its nine-day Pluto encounter.

After a journey of nearly a decade, New Horizons passed less than 7,800 miles from Pluto at 7:49 a.m. ET Tuesday. The probe is already more than 1 million miles farther into the Kuiper Belt, a region filled with ice-and-rocky bodies believed to be remnants left over from the formation of the solar system 4.6 billion years ago.

During the eons, Pluto has not been idle. Another surprise in the New Horizons’ first close-up was the complete lack of impact craters in the single frame that so far has been subject to scrutiny.

“We haven’t yet found a single impact crater on this image. This means this is a very young surface because Pluto has been bombarded by objects in the Kuiper Belt and craters happen. Just eyeballing it, we think (the surface) has to be probably less than 100 million years, which is a small fraction of the 4.5 billion-year age of the solar system. It might be active right now,” Spencer said.

A young surface means that Pluto has some mechanism for refreshing its face, one that requires an internal heat source. Scientists speculate that Pluto could hold a liquid ocean which gradually gives off heat as it freezes. Or it could still have radioactive materials from its formation that are releasing heat as they decay, perhaps driving ice volcanoes.

Whatever the source, the finding is significant since Pluto is the first icy world to be studied that isn’t orbiting a giant planet, and therefore doesn’t have tidal forces to power geologic processes.

“This is telling us that you do not need tidal heating to power ongoing recent geological activity on icy worlds. That’s a really important discovery that we just made this morning,” Spencer said.

New Horizons also found that Pluto’s big moon Charon is not geologically dead, defying predictions.

"Originally I thought Charon might be an ancient terrain covered in craters. Charon just blew our socks off when we had the new image today," said New Horizons deputy scientist Cathy Olkin, also with the Southwest Research Institute.

Read more at Discovery News

Jul 15, 2015

NASA's Pluto Mission: 'We Have a Healthy Spacecraft'

Right on time, New Horizons phoned home, letting its nervous flight control team -- and a huge crowd gathered at the mission operations center at Johns Hopkins University Applied Physics Lab near Baltimore -- that it had survived Tuesday’s close encounter with Pluto.

“We have a healthy spacecraft. We’ve recorded data of the Pluto system and we’re out of bound from Pluto,” New Horizons Mission Operations Manager (MOM) Alice Bowman announced after flight controllers confirmed the signals relayed by New Horizons.

It took the spacecraft more than nine years to travel the 3 billion miles to Pluto, which until Tuesday was the largest piece of unexplored real estate in the solar system.

Scientists and mission managers then had to wait another 13 hours after the spacecraft’s 7:49 a.m. ET close approach to learn if it survived the encounter. There was a 1-in-10,000 chance that a debris strike would destroy it.

“How often do we unlock the secrets of a new world? We did that today. How cool is that?” said Mark Holdridge, the New Horizons encounter mission manager.

“Your team made history today,” NASA’s associate administrator for science John Grunsfeld said after New Horizons phoned home.

New Horizons went right back to work, photographing and taking measurements of the backlit sides of Pluto and its primary moon Charon.

On Wednesday New Horizons will begin transmitting close-up pictures and science data collected during its 31,000 mph blitz past Pluto and its five moons. The images should be 10 times better resolution than what New Horizons transmitted in the hours leading up to its close encounter.

“We haven’t seen anything yet,” Grunsfeld said.

It will take New Horizons more than a year to empty its data recorders. The spacecraft, which is about the size of a piano, doesn’t carry the fuel to fire braking rockets and put itself into orbit around Pluto, so all its science was conducted on the fly, a throwback to NASA’s early exploration days of the 1960s, 70s and 80s.

Read more at Discovery News

Oldest Sperm Fossil Beats Prior Record by 30 Million Years

Sperm tends to be short lived and fragile, but scientists remarkably just found fossils for worm sperm in a cocoon that dates to 50 million years ago.

The sperm, described in the Royal Society journal Biology Letters, is so old that it predates the prior record-holder (fossilized sperm from a mussel shrimp) by over 30 million years.

The discovery “was a big surprise and almost pure chance,” lead author Benjamin Bomfleur of the Swedish Museum of Natural History told Discovery News. Almost, because he and senior author Stephen McLoughlin had previously found another super ancient item — a fossilized tiny protozoan animal — inside of a Triassic leech cocoon, also from Antarctica.

Bomfleur explained that earthworms, leeches and their relatives produce incredibly sturdy cocoons into which their eggs and sperm are released.

In this case, a scanning electron microscope at very high magnification revealed that sperm cells had become entrapped in the segmented worm’s cocoon wall material before it completely fossilized. Similar to bugs and plant bits trapped in amber, the sperm and its surrounding material later hardened and preserved over millions of years.

Based on the fossils, the sperm looked like that of a modern worm species.

The head of the sperm, which resembles drill bits, “(appears) strikingly similar to those of this one peculiar group of leech-like worms that is today only found living symbiotically on crayfish in the Northern Hemisphere,” Bomfleur said. “Quite perplexing!”

It could be that the worms had a much greater geographic range 50 million years ago than they do today. If that’s verified, and the reasons for the range shifts are determined, the information could shed future light not only on the early worm populations, but also on those of their shellfish hosts and other creatures in their ecosystem.

At the time of the prehistoric worm’s existence, the researchers believe what’s now Antarctica would have been much warmer, with a climate similar to that found today in southern Chile.

It appears to have been a mini paradise teeming with flora and fauna.

“The seas were brimming with sea life, with nautiloids (a mollusk group), sea urchins, clams and mussels, and a wide variety of sharks and other fish; on land, there was a diverse mammal fauna, ranging from small marsupials to large ungulates and sloths, as well as large cursorial (running) birds,” Bomfleur said.

He continued, “Isolated seeds of water lilies and lotus plants are common in the deposit where the cocoon was found, so we can expect that there were at that time also vegetated lakes or swamp areas.”

Read more at Discovery News

Climate Change Is Increasing Stress on Oceans

Climate change is seriously stressing out the oceans.

That’s the conclusion of a new study that used measurements of an array of human pressures on the ocean — from acidification to overfishing — to make a map of where those factors combined into stressed-out hotspots, as well as how the combinations of stressors had changed over time. They found that two-thirds of the world’s oceans were seeing increased pressure and that climate change accounted for most of those increases.

While the mapping effort doesn’t give a complete view and or address how the stressors are actually impacting various ecosystems, scientists not involved with the work said it is an important step in understanding the plight of the oceans and could inform policy decisions, showing where mitigation efforts are having a real impact.

Hotspots and ‘Hopespots’

“No part of the global ocean is without human influence,” the authors of the study, detailed in the journal Nature Communications, wrote. That influence comes from direct human impacts, such as trawling and fertilizer washed into the ocean, or more indirect ways, like the increased temperatures and carbon dioxide of the ocean that are a result of human emissions of greenhouse gases. Some 97 percent of the oceans are impacted by more than one of these issues.

Benjamin Halpern, of the University of California, Santa Barbara, and his team took data of a wide range of these factors, 19 in all, from satellites, computer models and fishery catch reports. They then combined them, yielding a map that showed where stressors were relatively high and low. They also compared the data from 2008 and 2013 to show where such pressures were high and going up and where they were low and abating — what Halpern calls hotspots and “hopespots.”

The team found that 66 percent of the oceans showed an increase in human stressors over the five-year period. Coastal regions, tropical and subtropical waters were particular areas that saw more impacts. About 5 percent of the oceans was heavily impacted and getting worse, including the North and East China seas, while 10 percent had low impact and was improving, such as the central Pacific.

“Not everywhere is going down the drain,” Halpern said. It “gives you hope that we can turn things around.”

The study found that climate change impacts were driving most of the increases in stress, which Halpern says shows how important it is to address climate change. But there is inherent inertia in the climate system — we’ll feel the impacts of today’s emissions for decades to come — so the map shows what other stressors can be addressed, and where, to see more immediate improvements.

Incomplete Story

Scott Doney, who studies acidification and nutrient loading at the Woods Hole Oceanographic Institution in Massachusetts and was not part of the study, said that while such work is important particularly for communicating with those outside the scientific community, “it’s not the complete story.” The study only looks at stressors, but not at what the actual impacts to particular ecosystems or species are.

“This is a first cut, you need to then dig down” to see impact on particular resources, Doney said.

Ken Caldeira, of Stanford University, made similar comments. “Any attempt to combine multiple stressors is going to be plagued by the issue of how to weight one stressor relative to another. The relative importance of different stressors will vary from species to species as well as from ecosystem to ecosystem,” he wrote in an email. Caldeira was also not involved in the study.

Read more at Discovery News

Exo-Doppelganger: Jupiter's Twin Seen Orbiting Sun's Twin

You don’t get to meet your double every day, but Jupiter and the sun share the same galaxy as their very own doppelgängers.

HIP 11915 is a sun-like star that not only looks like our sun, it is also the same mass and even the same age. But most remarkably, astronomers have discovered a world in orbit around that star that not only resembles gas giant Jupiter, it has a similar mass and also occupies a strikingly similar orbit.

This discovery has some fascinating implications for planetary formation and the possibility of truly Earth-like planets forming elsewhere in our galaxy.

Jupiter is well known to be the gravitational powerhouse of our solar system. The solar system was once a violent and tumultuous place, but the gravitational heft of Jupiter stabilized the inner solar system, making it a conducive environment to form Earth in a stable orbit inside our sun’s habitable zone.

Current theories also suggest that Jupiter had a huge part to play in “vacuuming” the inner solar system, clearing many errant asteroids and comets from slamming into a fledgling Earth. This had the effect of allowing life to gain a foothold on our planet, throttling the number of extinction-level impacts.

So, spotting another Jupiter in orbit around another sun-like star has striking implications for furthering our quest to find another planetary oasis and gives us an idea about how common planetary systems like ours may be.

“The quest for an Earth 2.0, and for a complete Solar System 2.0, is one of the most exciting endeavors in astronomy,” said Jorge Melendez, of the Universidade de São Paulo, Brazil, leader of the study and co-author of a paper to appear in the journal Astronomy and Astrophysics.

The astronomers used the powerful HARPS instrument that is mounted on th European Southern Observatory’s 3.6-meter telescope at the La Silla Observatory in Chile to spot the orbiting Jupiter-like world. HARPS uses the radial velocity method to tease out the slight wobble caused by the gravitational tugging of exoplanets on their parent stars. By deriving the frequency of the wobbles, astronomers can accurately calculate a planet’s mass, it’s orbital distance and period.

Read more at Discovery News

Jul 14, 2015

Why Did a Huge Pile of Boston Snow Linger Til Mid-July?

For months, Bostonians have marveled — or else recoiled in disgust — at a giant 75-foot-high, 4-acre pile of dirty snow left over from last winter’s record snowfall, which lingered for months in an empty lot on Tide Street in the city’s Seaport district.

The snow mountain actually was a man-made curiosity, the last of 11 such “snow farms” that Boston workers created out of desperation, as the city was inundated with frozen precipitation. The city’s Public Works department’s snowplows worked overtime, clearing the equivalent of 12 trips around the Earth’s equator,and deposited an astonishing 50,000 tons of snow at the snow farm sites.

But unlike the other piles of snow, the big kahuna didn’t melt. In a city filled with historic landmarks, it became a perversely odd sightseeing spot, one that curious passers-by often used as a backdrop for snapshots.

In April, a local resident posted a video of himself skiing down the side of the snow pile, a feat which required him to dodge refuse ranging from rusted lawn chairs to parking cones. (“This post-apocalyptic, sludge-coated amalgamation of snow … was good enough for me,” he commented afterward.)

Boston Mayor Martin J. Walsh even got in on the fun by staging the Boston Snow Melt Challenge, in which residents could guess when the Tide Street mound would finally melt away.

Finally, the Boston Globe reported on Monday morning that the last of the once-giant mound of snow apparently had melted. “Based on my close proximity this morning, it’s really just a pile of trash at this point,” Elise Musumano, an employee at a nearby business, told the Globe.

But you probably have a question lingering in your mind. Why did the giant snow pile last until mid-summer? The reason is that snow and ice don’t just instantly melt when the surface air temperature rises above freezing. As the physics website Splung.com, explains, when a substance is in the solid phase, it requires additional energy to break the bonds holding its molecules in place. That necessary phase-changing energy is called latent heat.

While solar radiation provided a potential source of that energy, getting it to penetrate the snow mound was another thing entirely. As this Boston Globe article explains, the mound was filled with air pockets, which served as an effective insulator. Rain would have helped to break down that insulation by piercing the mound’s surface. But unfortunately, Boston had a spring that was relatively dry as well as being unusually cold.

From Discovery News

Pentaquarks: LHC Has Discovered an Exotic Particle

Now that the Large Hadron Collider (LHC) is smashing protons together at record energies, physicists are hoping to discover new and exotic particles emerge from the collisions. But there are a few unsolved mysteries surrounding different configurations of known subatomic particles that still have to be wrapped up.

And today, CERN announced the discovery of the “pentaquark” — a collection of five quarks bound together to form an exotic state of matter, a particle that has been theorized for some time but other experiments have had a hard time nailing down a true detection.

“The pentaquark is not just any new particle,” said Guy Wilkinson, spokesperson for the LHCb experiment at the LHC, in a CERN press release. “It represents a way to aggregate quarks, namely the fundamental constituents of ordinary protons and neutrons, in a pattern that has never been observed before in over fifty years of experimental searches. Studying its properties may allow us to understand better how ordinary matter, the protons and neutrons from which we’re all made, is constituted.”

Quarks are the subatomic constituents of regular particles, called hadrons. Hadrons come in two varieties, baryons (which contain 3 quarks) and mesons (which contain 2 quarks). Protons and neutrons are baryons where, for example, a proton is composed of 2 “up” quarks and 1 “down” quark; a neutron has 2 “down” quarks and 1 “up” quark.

But in the 1960′s, theorists realized that the Standard Model also allows the formation of 5 quarks in the same particle, known as a pentaquark. But experimental searches for this elusive 5-quark particle kept drawing blanks and any vaguely positive detection was quickly shot down by follow-up experiments.

Now, a strong signal in the LHCb detector has led to the pentaquark’s discovery.

LHCb physicists examined the decay of a baryon known as Lambda b (Λb) into 3 other particles, the J-psi (J/ψ-), a proton and a charged kaon. By using the highly sensitive detector to characterize the masses of these decay products, the physicists were able to see that intermediate states were sometimes involved in their production. They named these intermediate states Pc(4450)+ and Pc(4380)+ and indicate that pentaquarks are at play.

In a nutshell, the physicists noticed a signal emerge from the post-collision noise of particles. This signal, or “excess,” indicated the creation of J/ψ-, protons and kaon in quantities predicted by theories surrounding subatomic decay processes that involve pentaquarks. The decay particles acted as a “fingerprint” of sorts.

“Benefiting from the large data set provided by the LHC, and the excellent precision of our detector, we have examined all possibilities for these signals, and conclude that they can only be explained by pentaquark states,” said Tomasz Skwarnicki, a LHCb physicist from Syracuse University, New York. “More precisely the states must be formed of two ‘up’ quarks, one ‘down’ quark, one ‘charm’ quark and one ‘anti-charm’ quark.”

Read more at Discovery News

Big Day for Little Pluto: Probe Makes Flyby

After tearing through space for 9.5 years, putting 3 billion miles on its odometer, NASA’s low-cost New Horizons spacecraft made it past Pluto, the last major unexplored piece of real estate in the solar system -- or so scientists hope.

Confirmation that New Horizons survived its brush by Pluto and its five known moons won’t come until 8:53 p.m. EDT Tuesday. But that didn’t stop the celebrations at New Horizons mission control center at the Johns Hopkins University Applied Physics Lab outside Baltimore.

“It’s truly a mark in human history,” said NASA’s associate administrator for science John Grunsfeld. “It’s been an incredible voyage.”

As New Horizons approached Pluto, scientists began realizing they were looking at a far more active world than initially imagined. The probe relayed its closest view yet on Monday before going into radio silence for the flyby. NASA released the image on Tuesday.

“What we’ve seen already from Pluto is that it’s a complex, interesting world,” Grunsfeld told reporters after the flyby.

With 99 percent of New Horizons flyby data still onboard the spacecraft, mission managers and scientists have a nervous wait ahead.

“Hopefully it survived the passage, we’re counting on that,” said lead scientist Alan Stern, with the Southwest Research Institute in Boulder, Colo.

New Horizons was on track to fly within 7,750 miles of Pluto at 7:49 a.m. EDT. Mission operations manager Alice Bowman said the latest data from the spacecraft showed it would arrive 72 seconds early, well within the targeted time for the planned encounter.

From Discovery News

Human Hands More Primitive than Chimp Hands

Given our inherent human-centric viewpoint, we tend to think that our species is more advanced in all respects than other animals, but new research finds that human hands are more primitive than those of our closest primate ancestors: chimpanzees.

The study, published in the latest issue of the journal Nature Communications, determined that while human hand proportions have changed little from those of the last common ancestor of chimps and humans, the hands of chimps and orangutans have evolved quite a bit.

“The findings suggest that the structure of the modern human hand is largely primitive in nature, rather than, as some believe, the result of more recent changes necessary for stone tool-making,” Kurtis Hiatt, a spokesperson for The George Washington University, told Discovery News.

Sergio Almécija, a scientist in the university’s Center for the Advanced Study of Human Paleobiology, led the study, which was co-authored by Jeroen Smaers and William Jungers. Smaers and Jungers are researchers at Stony Brook University, where the research was conducted.

The researchers came to their conclusions after analyzing the hands of humans, chimps and orangutans, as well as the remains of hands for early apes like Proconsul heseloni and the hands of human ancestors, such as Ardipithecus ramidus and Australopithecus sediba.

Almécija and his team discovered that human hands today are not that different from those of the early human ancestors.

“Human hands are marked by a relatively long thumb when compared to the length of their four other fingers — a trait that is often cited as one of the reasons for the success of our species because it facilitates a ‘pad-to-pad precision grip,’” Hiatt said.

Conversely, chimp hands are much longer and narrower. Since the thumb is not as long, it just meets up with the palm, while the chimp’s other four fingers extend upward. As a result, chimps and orangutans do not have opposable thumbs as we do.

Gorillas also appear to have inherited our more primitive hand structure. Like human hands, gorilla hands have five fingers, including an opposable thumb. Gorilla feet are similar to ours too. Each gorilla foot has five toes, but their big toe is opposable and can move much more flexibly than ours can.

Almécija and his colleagues suspect that all living primates survived a late Miocene (12 to 5 million years ago) extinction event by specializing to exist in certain habitats. While chimps and orangutans became tree-climbing specialists, humans evolved to become more terrestrial. Gorillas did too.

Read more at Discovery News

Jul 13, 2015

Clear Horizons? Now For Your Pluto Space Weather Report

Pluto may be, on average, 40 times further away from the sun than Earth, but that doesn’t mean it doesn’t experience the sun’s outbursts. And it just so happens that, although it’s extremely difficult to gauge the location and intensity of solar particle clouds at 3.7 billion mile away, a NASA supercomputer has taken on the task and arrived at a space weather report of sorts just in time for New Horizons’ flyby.

As discussed in the video below, it takes around 5 months for a coronal mass ejection (CME) to travel from the sun to the orbit of Pluto (as a comparison, CMEs take between hours to a couple of days to reach Earth), but interplanetary space is a complex environment and it takes some extreme computing power to simulate these energetic clouds of magnetized plasma over those distances.

CMEs are launched from the sun’s highly magnetized lower corona (the sun’s atmosphere) and are composed of ionized particles that can interact with planetary magnetic fields. Should a CME be “geoeffective” when encountering our planet’s magnetosphere, for example, a geomagnetic storm can be triggered, producing spectacular aurorae at high latitudes.

Pluto is much further away from the sun, and by the time a CME reaches the dwarf planet, the plasma will have been stretched out and much less dense than a CME encountering Earth — so the CME is more of a “gentle breeze” by this point. It is currently unknown whether Pluto possesses a magnetic field, but space weather will undoubtedly affect the dwarf planet’s surface, depositing solar plasma, possibly driving some interesting chemistry.

As for the New Horizons flyby, don’t expect anything spectacular in the way of space weather. On July 14, it seems that CME activity should be extremely low during flyby, with a higher density front encountering Pluto later, which could impact the small world’s tenuous atmosphere.

“Our simulation estimates that during the New Horizon approach, Pluto might be immersed in a region with very low solar wind densities, lasting for about one month,” Dusan Odstricil, of NASA's Goddard Space Flight Center in Greenbelt, Md., told Spaceweather.com. “This will be followed by a large merged region, which could significantly compress Pluto’s atmosphere.”

Read more at Discovery News

Confirmed: Pluto is Reigning King of the Kuiper Belt

New measurements made by NASA’s New Horizons spacecraft confirm Pluto actually is the reigning king of the Kuiper Belt, with a diameter that surpasses the size of Eris, another so-called “dwarf planet” in the solar system’s backyard.

“That settles the debate about the largest object in the Kuiper Belt,” New Horizons lead scientist Alan Stern, with the Southwest Research Institute in Boulder, Colo., told reporters Monday.

The observations, relayed as New Horizons neared Pluto after a 9.5-year, 3 billion mile journey, show that Pluto spans about 1,473 miles in diameter. Scientists suspect the maximum diameter for Eris, which circles the sun about three times farther than Pluto, is 1,445 miles.

Pluto’s size has been somewhat of a mystery because the planet’s atmosphere makes it somewhat blurry against the light of background stars, which are used as measurement tools.

With a slightly larger diameter than predicted, Pluto is a little less dense, with a higher percentage of ice and a little less rock. The measurement also means Pluto’s troposphere, its lowest layer of atmosphere, is closer to the ground than some computer models predict.

Early analysis of New Horizons data also shows that more of Pluto’s nitrogen atmosphere is escaping into space, or an unknown transport mechanism is ramping-up the process. On Tuesday, New Horizons will be able to see if Pluto is sharing any of its atmosphere with its primary moon and orbital partner Charon.

The discoveries are just a hint of what scientists expect from New Horizons as it punches through the Pluto system Tuesday morning, then looks back at its quarry for several more hours.

“This science is already mouth-watering,” Stern said.

Although within 650,000 miles of Pluto, the difference between what New Horizons’ cameras saw on Monday and what they will image when the spacecraft passes about 7,750 miles from Pluto (and about 18,000 miles from Charon) on Tuesday. Image resolution will jump from 15 kilometers per pixel to less than 100 meters, an improvement of more than two orders of magnitude, Stern said.

Read more at Discovery News

Pluto's Moon Charon Hosts Craters and Monster Canyon

While all eyes are on Pluto, NASA’s New Horizons mission is also beaming back intriguing views of the dwarf planet’s largest moon, Charon.

A starkly different color to Pluto, Charon seems to have its own highly complex geology featuring large craters and a spectacular canyon, which is longer and miles deeper than Earth’s Grand Canyon. In short, Charon is shaping up to be the second arena of discovery as New Horizons prepares for close approach to the Pluto system hours from now.

“This is the first clear evidence of faulting and surface disruption on Charon,” said William McKinnon, deputy lead scientist with New Horizon’s Geology and Geophysics investigation at Washington University in St. Louis, Mo. “New Horizons has transformed our view of this distant moon from a nearly featureless ball of ice to a world displaying all kinds of geologic activity.”

The largest chasm looks like a deep scar in the moon’s southern hemisphere and the most prominent crater, measuring approximately 60 miles (a little under 100 kilometers) is seen close to its south pole.

In this observation captured by the mission’s Long Range Reconnaissance Imager (LORRI) in July 11, bright rays can be seen surrounding the crater, indicating that the impact occurred relatively recently in geological timescales. These rays were formed when an impactor scoured into Charon’s surface, blasting bright ejecta across the darker landscape.

The New Horizons team are particularly interested in the surprising darkness of the crater’s floor according to a press release issued on Sunday. One theory is that when Charon was hit, the impactor exposed darker layers of icy material below the surface. Another possibility is that the material inside the crater is the same material on the surface of the moon, but has taken the form of larger grain sizes, which reflect less light.

Read more at Discovery News

Rare Harpy Eagle Chick Captured in New Pics

Harpy eagles nesting high above the understory of the Peruvian rainforest have been captured in a series of stunning new photos.

One of the eagles is a mama bird, while the other is an adorable eagle chick.

Because the giant bird of prey lives in the darkest portions of the rainforest and hunts its quarry in dead silence, many Peruvian Amazon birders can go their entire lives without seeing one, said nature photographer Jeff Cremer, who photographed the eagles.

“It’s about as rare as seeing a unicorn,” Cremer told Live Science.

Rare creatures

Harpy eagles (Harpia harpyja) are imposing creatures. The massive birds can be up to 3 feet (0.9 meters) tall, with wingspans reaching 6 feet (1.8 m), Cremer said. Like stealth bombers, the birds of prey glide silently; they move through the shadows of the rainforest, hunting sloths, monkeys and even an occasional deer, Cremer said. To better hunt their prey, the eagles can turn their heads 180 degrees to face upward while flying through the dense rainforest, and can also fluff up their white head feathers, creating an acoustic funnel to direct sound to their ears.

When they do capture an unsuspecting animal, the eagles crush it, killing it instantly with their huge talons, which can produce hundreds of pounds of force, Cremer added.

“They have claws the size of an adult grizzly bear,” Cremer told Live Science.

But the eagles are tough to spot, because they build their nests in the dark region between the forest’s understory and canopy, high up in the trees, where the limbs just begin to branch out. In addition, logging and illegal mining have sharply reduced the harpy eagle’s natural habitat and the majestic hunter is now considered near threatened by the International Union for the Conservation of Nature. As a result, seeing a harpy eagle chick in the wild in this region is incredibly rare, Cremer said.

Baby bird

Guides at the Tambopata Research Center in Peru first became aware of the birds of prey after noticing a nest high up in the trees. The guides also saw a harpy eagle fly over their heads, carrying the head of a half-eaten sloth to the nest, which contained a single chick. After monitoring the nest, Cremer and his colleagues decided to climb up to take photos.

Getting those pictures was no easy feat. The nest was perched high in the branches of an ironwood tree, about 100 feet (30 m) above the ground, so the team had to toss a slingshotlike rope up to the branches and then ascend using special climbing gear.

Read more at Discovery News

Jul 12, 2015

Amazing flare from a black hole in a distant galaxy

Five billion years ago, a great disturbance rocked a region near the monster black hole at the center of galaxy 3C 279. On June 14, the pulse of high-energy light produced by this event finally arrived at Earth, setting off detectors aboard NASA's Fermi Gamma-ray Space Telescope and other satellites. Astronomers around the world turned instruments toward the galaxy to observe this brief but record-setting flare in greater detail.

"One day 3C 279 was just one of many active galaxies we see, and the next day it was the brightest thing in the gamma-ray sky," said Sara Cutini, a Fermi Large Area Telescope scientist at the Italian Space Agency's Science Data Center in Rome.

3C 279 is a famous blazar, a galaxy whose high-energy activity is powered by a central supermassive black hole weighing up to a billion times the sun's mass and roughly the size of our planetary system. As matter falls toward the black hole, some particles race away at nearly the speed of light along a pair of jets pointed in opposite directions. What makes a blazar so bright is that one of these particle jets happens to be aimed almost straight at us.

"This flare is the most dynamic outburst Fermi has seen in its seven years of operation, becoming 10 times brighter overnight," said Elizabeth Hays, a Fermi deputy project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Astronomers think some change within the jet is likely responsible for the flare, but they don't know what it is.

The brightest persistent source in the gamma-ray sky is the Vela pulsar, which is about 1,000 light-years away. 3C 279 is millions of times farther off, but during this flare it became four times brighter than Vela. This corresponds to a tremendous energy release, and one that cannot be sustained for long. The galaxy dimmed to normal gamma-ray levels by June 18.

The rapid fading is why astronomers rush to collect data as soon as they detect a blazar flare. "Our priority is to make observations while the object is still bright," said Masaaki Hayashida, a Fermi team member at the University of Tokyo's Institute for Cosmic Ray Research. "Once it's over, we can start trying to understand the mechanisms powering it."

The Italian Space Agency's AGILE gamma-ray satellite first reported the flare, followed by Fermi. Rapid follow-up observations were made by NASA's Swift satellite and the European Space Agency's INTEGRAL spacecraft, which just happened to be looking in the right direction, along with optical and radio telescopes on the ground.

3C 279 holds a special place in the history of gamma-ray astronomy. During a flare in 1991 detected by the EGRET instrument on NASA's then recently launched Compton Gamma Ray Observatory (CGRO), which operated until 2000, the galaxy set the record for the most distant and luminous gamma-ray source known at the time. "Although we didn't expect to find the galaxy so bright, we soon had a much greater surprise," recalled Robert Hartman, who led the first gamma-ray study of 3C 279 with CGRO and is now a member of the Fermi team at Goddard. "Its brightness varied substantially, becoming four times brighter within 10 days."

Read more at Science Daily

'Planet' Pluto Has Complex and Interesting Geology

As NASA’s New Horizons spacecraft barrels toward Pluto, rapidly approaching its close encounter on July 14, long-distance reconnaissance by the probe is revealing a fascinating surface geology.

Far from being a bland, uniform surface, the dwarf planet seems to play host to a complex array of geological features that planetary scientists are already trying to decipher.

“We’re close enough now that we’re just starting to see Pluto’s geology,” said Curt Niebur, New Horizons program scientist at NASA Headquarters in Washington, D.C., in a Friday news release.

Of particular interest is the “whale” feature that can be seen covering the lower-left region of Pluto’s globe in this Long Range Reconnaissance Imager (LORRI) observation. Although it’s too early to tell, this dark shape seems to be some kind of plain, starkly contrasting with the surrounding, brighter landscape.

Niebur is particularly interested in the gray region immediately above the whale’s “tail”: “It’s a unique transition region with a lot of dynamic processes interacting, which makes it of particular scientific interest.”

“Among the structures tentatively identified in this new image are what appear to be polygonal features; a complex band of terrain stretching east-northeast across the planet, approximately 1,000 miles long; and a complex region where bright terrains meet the dark terrains of the whale,” added New Horizons principal investigator Alan Stern. “After nine and a half years in flight, Pluto is well worth the wait.”

The imagery coming from New Horizons is becoming more and more detailed as the probe approaches. This particular LORRI image was captured on July 9 from a distance of 3.3 million miles (5.4 million kilometers), but even from this distance the camera is able to deliver a resolving power of 17 miles per pixel.

On Tuesday, New Horizons will make its historic close approach to Pluto and its moons, giving us a close-up view of the last of the “classical” nine planets of the solar system to be explored by a robotic flyby mission. There is little doubt that this encounter, and the science it will gather, will not only enrich our understanding of the very early formation of our solar system (Pluto is an ancient “open book” of geological record), it will also stir the debate surrounding Pluto’s planetary status.

In 2006, Pluto suffered what was widely regarded as a “demotion” of sorts, when it was re-catagorized by the International Astronomical Union (IAU) from being a “planet” to a “dwarf planet.” The motivation for this reclassification focused on the new and exciting Kuiper Belt discoveries that were cropping up as observational techniques became more sophisticated. Rather than the classical “nine planets,” astronomers found themselves swamped with a solar system possibly containing hundreds of planets.

Unfortunately for Pluto, it became a rounding error and fell into a new group of planetary bodies: dwarf planets.

Over the years, the “Pluto debate” has ebbed and flowed in the public and scientific arena with polarized opinions on both sides focusing on what is considered to be a planet and what isn’t. The definition of a planet (using the IAU’s golden rules for what a planet is) will, however, seem completely archaic when New Horizons beams back a growing archive of close-up observations of this alien world after flyby (the mission is expected to take months to transmit all of its Pluto close encounter data, according to Stern).

For what it’s worth, I think that we are currently exploring a completely different class of planetary body, not based on its physical size, but on its unique configuration. Largest moon Charon doesn’t orbit Pluto; Pluto and Charon orbit a common point (known as a “barycenter”) in space above Pluto’s surface. Charon’s mass is so large that on each orbit, it tugs Pluto off-center, causing it to wobble. As discussed in previous Discovery News articles, the case for the Pluto-Charon system being a “binary planet” is an interesting one.

Read more at Discovery News