On Tuesday (Jan. 19), one of the world’s driest places awoke to an otherworldly dusting of frost.

In the Sahara Desert of northwestern Algeria, just outside the town of Ain Sefra, sand dunes were streaked with ice crystals as far as the eye could see. Local photographer Karim Bouchetata captured the unusual weather in pictures and videos that have since made headlines around the world.

Ain Sefra sits about 3,280 feet (1,000 meters) above sea level and is surrounded by the Atlas Mountains, near the Algerian-Moroccan border. While summer temperatures in the region regularly soar above 100 degrees Fahrenheit (38 degrees Celsius), January days average a much milder 57 F (14 C), according to Sky News. Tuesday’s ethereal display of frost followed a rare night of 27-F (minus 3 C) temperatures.

Snow and ice accumulation in the northern Sahara is unusual, but not unprecedented. Tuesday’s dusting marks the fourth time in 42 years that Ain Sefra has seen snow, with previous occurrences in 1979, 2016 and 2018. Those past snowfalls were much heavier than this week’s display; in 2018, some areas of northwestern Algeria saw up to 15 inches (40 centimeters) of snow, while the 2016 blizzard dumped more than 3 feet (1 m) in select regions, Live Science previously reported.

Photographer Karim Bouchetata takes in the surreal, icy landscape around him. (Image credit: Karim Bouchetata)

The Sahara is the largest hot desert in the world, stretching more than 3.3 million square miles (8.6 million square kilometers) across northern Africa between the Atlantic Ocean and the Red Sea. (Antarctica and the Arctic, which each cover more area than the Sahara, are both considered cold deserts).

The Sahara is much more likely to see snowfall at higher altitudes, such as in the Atlas Mountains, NASA said in a statement following the 2018 snow dump, which was visible from space. The Moroccan side of the Atlas Mountains also saw substantial snowfalls in 2005 and 2012, according to NASA.

Via Live Science

The post Ice covers the Sahara Desert for just 4th time in 50 years appeared first on tunhien.net.

Preservation of figure carved from single piece of wood is incredible, say archaeologists

An extremely rare, carved wooden figure from the early Roman era has been unearthed in a waterlogged ditch in Buckinghamshire, the latest extraordinary find in the UK’s biggest ever archaeological dig along the 150-mile HS2 rail route.

The 67cm-tall figure is carved from a single piece of wood. Archaeologists said its preservation was “incredible” given its age and material, but the lack of oxygen in the ditch helped prevent rotting over many centuries.

“This is a truly remarkable find which brings us face to face with our past. The quality of the carving is exquisite and the figure is all the more exciting because organic objects from this period rarely survive,” said Jim Williams, a senior science adviser for Historic England.

The figure, found in a field near Twyford, is wearing a knee-length tunic that seems to be gathered at the waist. It may be wearing a hat, or have styled hair, and has well-defined legs, although the feet and the arms below the elbows have degraded.

More than 1,000 archaeologists have been working on at least 60 separate sites along the HS2 phase one route between London and Birmingham since autumn 2018. Experts have said the project is a once-in-a-generation opportunity to shed light on 10,000 years of history.

The route was initially mapped by laser scanning and geophysical surveys before digs began. Archaeological investigation is a legally binding condition of the HS2 project, and is funded as part of the overall budget, estimated in 2019 at £45bn for phase one.

The figure, found in a field near Twyford, is wearing a knee-length tunic that seems to be gathered at the waist. Photograph: HS2

Among the finds ranging from the iron age to the Victorian era is the discovery revealed earlier this week of a vast Roman settlement in Northamptonshire, 16th-century gardens in Warwickshire, the world’s oldest railway roundhouse in Birmingham, a trio of Roman statues at an abandoned medieval church in Buckinghamshire, and tens of thousands of skeletons at various burial grounds.

“The scale of the HS2 project is unprecedented, so it’s not surprising that spectacular discoveries have been made,” said Mike Pitts, editor of British Archaeology. “It’s the fruits of Britain’s thousands of years of continuous occupation and our skilled archaeological workforce.”

Alice Roberts, presenter of the BBC programme Digging for Britain, said the “extraordinary finds” along the HS2 route showed how rich the archaeological landscape of the country was. “This is the biggest archaeological investigation we’ve ever seen in Britain and you can’t overstate the importance of it,” she said.

Objects that have been unearthed will be preserved and many will eventually be displayed in museums. But larger finds, such as the 10 metre-wide Roman road in Northamptonshire, will be bulldozed to make way for HS2.

Helen Wass, HS2’s head of heritage, said: “Archaeology is a double-edged sword. We wouldn’t be doing it if construction wasn’t happening. You can’t have one without the other. We make sure that if construction happens, we record our heritage to the best of our ability.”

The cost of the HS2 archaeological work is built into the project’s overall budget, but Wass declined to say how much it had cost so far. Fieldwork on phase one is expected to be completed by the end of 2022, but post-excavation analysis will take several more years, she said.

The carved wooden figure was “a fantastic find”, said Pitt. “It’s really rare to get Roman carved woodwork in Britain. Even in its fractured, weathered state, it has something in the pose of the figure and in the dress that says this is probably Roman.”

The figure will undergo analysis and conservation at York Archaeology. A fragment that was found broken off in the ditch will be radiocarbon-dated to establish an accurate date for the wood.

Via The Guardian

The post ‘Exquisite’ Roman figure found on HS2 dig in Buckinghamshire appeared first on tunhien.net.

Mission is step closer to exploring most energetic and exotic celestial objects in universe

Nasa’s Imaging X-ray Polarimetry Explorer (IXPE) has successfully extended its 4-metre boom arm to assume its operational configuration.

Launched on 9 December atop a SpaceX Falcon 9 rocket from the Kennedy Space Centre in Florida, IXPE is a space observatory designed to study X-rays from black holes, neutron stars and other exotic celestial objects.

To bring X-rays into focus requires a long telescope because mirrors cannot bend the highly energetic rays by large amounts. Instead they have to be coaxed into focus with a device called a grazing incidence telescope. IXPE has three of these. Each sits on the end of the boom arm and directs light into the instruments in the body of the spacecraft.

By measuring the polarisation of the X-rays, IXPE will reveal information about the magnetic environment of their targets. At launch the spacecraft was roughly cubic, about 1-metre long on each side, with the 4-metre-long boom arm folded into a canister 0.3 metres in length. This allowed the IXPE to fit into the nose cone of the rocket. On 15 December, the spacecraft extended the boom. Mission personnel are now working to commission the telescope, ready for science observations to begin in the new year.

The post Nasa’s X-ray boom arm for black hole studies extends in orbit appeared first on tunhien.net.

They’re difficult to find, a pain to grow and lose their sexy aroma within a week

Truffles — the non-chocolate kind, sorry — are edible fungi, like mushrooms. Unlike mushrooms, they grow underground near tree roots and the best truffles are wildly, insanely, wait-how-much? expensive, sometimes as much as thousands of dollars per pound.

Truffles are costly because they’re hard to find, frustrating to grow, and impossible to store for any length of time. They generally range from strawberry- to apple-sized, though larger ones have been discovered.

Though multiple species are found worldwide, prestige truffles come from specific areas, much like wine from celebrated regions of Europe and California.

Black truffles from France and white truffles from Italy are the two most highly valued. Even though they resemble evil spores from a 1960s Outer Limits episode, truffles are prized delicacies in gastronomy, the art of cooking and eating good food.

Some U.S entrepreneurs are cultivating truffles to become part of an industry estimated to grow to nearly $6 billion globally over the next two decades.

Truffle farms face formidable agricultural challenges, since truffles thrive only in a narrow band of weather conditions. Black truffles, for example, need mild winters, no frost, warm (not hot) summers, and dry winters, according to modernfarmer.com.

Grow a good truffle, however, and you’ll be rewarded by food fanatics clamoring for a seat at your table.

Ask aficionados to describe truffles and you’ll get baskets of adjectives: garlicky, mushroomy, earthy, pungent, musky, gamey. That’s because the truffle’s flavor comes not from its taste, but its aroma. Writers wax poetic about it:

“Presently, we were aware of an odour gradually coming towards us, something musky, fiery, savoury, mysterious, — a hot drowsy smell, that lulls the senses, and yet enflames them — the truffles were coming.”
— William Makepeace Thackeray, Memorials of Gormandizing, 1841
Truffles get their peculiar odor from a multitude of chemicals. In white truffles, bis(methylthio)methane is the key compound, according to the American Chemical Society. In black truffles, dimethyl sulfide and 2-Methylbutanal are found.

In addition to those scent molecules, truffles have pheromones, chemical substances that affect animals and insect behavior. They have androstenol, a steroidal pheromone found in humans, and androstenone, which boars produce for mating.

Modern research suggests truffles affect people because of the human pheromone. Others have commented on the phenomenon:

“The truffle is not a positive aphrodisiac, but on occasion it can make women more loving and men more lovable.”
— Alexandre Dumas, Grand Dictionnaire de Cuisine, 1871
The smell is also why pigs were originally used to sniff out truffles — they were drawn to the boar pheromone. Specially trained dogs are employed these days, since they don’t gobble up truffles as pigs do.

Unfortunately the unique odor starts to fade as soon as the truffle is dug up. Truffles don’t last longer than 7 to 10 days.

Truffles can be cooked, but are usually cleaned by hand and grated or sliced paper-thin atop warm food, which absorbs the truffle’s aroma. Other cooks put truffles in closed containers with food to impart a truffle flavor. You don’t need much since a little goes a long way.

In lieu of actual truffles, some people use less expensive truffle oil, which is “cooking oil, such as olive or sunflower oil, that has been infused with the aroma of white or black truffles,” according to Bon Appétit magazine.

Black truffles served over polenta, a type of yellow cornmeal.

It can be difficult to find truffle oil that includes real truffles. It’s out there, but most of it is cooking oil scented with chemicals found in truffles (but not truffles themselves).

You shouldn’t cook with truffle oil since heat tends to alter it, advises RecipeGeek. It’s considered a finishing oil, best when sprinkled sparingly over prepared food like eggs, cooked vegetables, pasta or potatoes. Even french fries are subjected to the treatment.

Truffle oil has its passionate defenders and detractors. Anthony Bourdain, the late celebrity chef, was unsparingly critical:

“Truffle oil. It’s horrible. It’s not even food. It’s really on a par with — about as edible as Astroglide, and made from the same stuff.”

Via USA Today

The post Why are truffles so darned expensive? appeared first on tunhien.net.

China’s ‘artificial sun’ set a new world record on Thursday by running for 1,056 seconds at high plasma temperature, the longest duration for an experimental advanced superconducting tokamak (EAST) fusion energy reactor, Xinhua News Agency reported.

EAST already scored a previous record in May, running for 101 seconds at a temperature of 120 million degrees Celsius.

The latest one came after it was announced last week that a new round of testing would be conducted by the Institute of Plasma Physics under the Chinese Academy of Sciences (ASIPP).

The institute, located in Hefei, east China’s Anhui Province, has discharged electricity more than 10,000 times since the inauguration of phase II of EAST in 2011.

Designed to mimic a fusion reaction like the Sun using hydrogen and deuterium gases as fuel, EAST will provide insights into plasma physics research that is crucial to establish industrial-size reactors to generate clean energy, according to the China National Nuclear Corp.

Fusion energy is considered the ideal “ultimate energy” for a carbon-neutral energy future as hydrogen and deuterium gases are abundant in the sea.

The institute has also been collaborating with high-emission enterprises to help them achieve carbon neutrality, according to ASIPP director Song Yuntao.

EAST’s record-breaking performance also topped the list of 10 sci-tech news for 2021 in China by China Media Group.

Now EAST has reached all three targets separately – 1-million-ampere current, 1,000-second duration and 100-million-degree-Celsius temperature. The final mission for the tokamak is to reach all the targets in one try.

Via CGTN

The post China’s ‘artificial sun’ smashes 1000-second fusion world record appeared first on tunhien.net.

A tiger was found dead in Chhindwara of Madhya Pradesh on Wednesday, taking this year’s toll in the state to 44. According to reports, two days ago, a tigress died in the state’s Dindori area allegedly due to poisoning.

As many as 126 tigers died in India in 2021, the National Tiger Conservation Authority (NTCA) said on Thursday, asserting that it is looking into the cause of the recent death of a big cat in Madhya Pradesh.

A tiger was found dead in Chhindwara of Madhya Pradesh on Wednesday, taking this year’s toll in the state to 44. According to reports, two days ago, a tigress died in the state’s Dindori area allegedly due to poisoning.

An official from the NTCA said the number of tiger deaths has increased in 2021, and investigations are ongoing.

The official, who did not wish to be named, said several measures are being taken to protect tigers which include patrolling and arresting people for poaching.

He said there can be many causes for the death as the population of tigers is huge, and a standard operating procedure (SoP) is followed to ascertain the reasons.

The official said the tiger death is under scrutiny of the state as well as the NTCA.

The official also rejected reports that claimed the tigress in Madhya Pradesh died due to poisoning in Dindora, saying they are “mere assumptions” as scrutiny takes time.

“Ongoing process to protect tigers like patrolling is going on, and a lot of people have been arrested for poaching too. We are doing everything to protect the tigers, but we should also understand that nearly 30 per cent of them are outside tiger reserves,” the official said.

As per the NTCA, the maximum tiger deaths this year took place in Madhya Pradesh (44), followed by 26 in Maharashtra and 14 in Karnataka.

Via Hindustan Times

The post 126 Tiger Deaths Recorded In India 2021: NTCA appeared first on tunhien.net.