Cube-shaped ice is rare, at least at the microscopic level of the ice crystal. Now researchers have coaxed typically hexagonal 3-D ice crystals to form the most cubic ice ever created in the lab.
Cubed ice crystals — which may exist naturally in cold, high-altitude clouds — could help improve scientists’ understanding of clouds and how they interact with Earth’s atmosphere and sunlight, two interactions that influence climate.
Engineer Barbara Wyslouzil of Ohio State University and colleagues made the cubed ice by shooting nitrogen and water vapor through nozzles at supersonic speeds. The gas mixture expanded and cooled, and then the vapor formed nanodroplets. Quickly cooling the droplets further kept them liquid at normally freezing temperatures. Then, at around –48° Celsius, the droplets froze in about one millionth of a second.
The low-temperature quick freeze allowed the cubic ice to form, the team reports in the July 20 Journal of Physical Chemistry Letters. The crystals weren’t perfect cubes but were about 80 percent cubic. That’s better than previous studies, which made ice that was 73 percent cubic.
Neandertals took stick-to-itiveness to a new level. Using just scraps of wood and hot embers, our evolutionary cousins figured out how to make tar, a revolutionary adhesive that they used to make formidable spears, chopping tools and other implements by attaching sharp-edged stones to handles, a new study suggests.
Researchers already knew that tar-coated stones date to at least 200,000 years ago at Neandertal sites in Europe, well before the earliest known evidence of tar production by Homo sapiens, around 70,000 years ago in Africa. Now, archaeologist Paul Kozowyk of Leiden University in the Netherlands and colleagues have re-created the methods that these extinct members of the human genus could have used to produce tar. Three straightforward techniques could have yielded enough adhesive for Neandertals’ purposes, Kozowyk’s team reports August 31 in Scientific Reports. Previous studies have found that tar lumps found at Neandertal sites derive from birch bark. Neandertal tar makers didn’t need ceramic containers such as kilns and didn’t have to heat the bark to precise temperatures, the scientists conclude. These findings fuel another burning question about Neandertals: whether they had mastered the art of building and controlling a fire. Some researchers suspect that Neandertals had specialized knowledge of fire control and used it to make adhesives; others contend that Neandertals only exploited the remnants of wildfires. The new study suggests they could have invented low-tech ways to make tar with fires, but it’s not clear whether those fires were intentionally lit.
“This new paper demystifies the prehistoric development of birch-bark tar production, showing that it was not predicated on advanced cognitive or technical skills but on knowledge of familiar, readily available materials,” says archaeologist Daniel Adler of the University of Connecticut in Storrs, who did not participate in the study. Kozowyk’s group tested each of three tar-making techniques between five and 11 times. The lowest-tech approach consisted of rolling up a piece of birch bark, tying it with wood fiber and covering it in a mound of ashes and embers from a wood fire. Tar formed between bark layers and was scraped off the unrolled surface. The experimenters collected up to about one gram of tar this way.
A second strategy involved igniting a roll of birch bark at one end and placing it in a small pit. In some cases, embers were placed on top of the bark. The researchers either scraped tar off bark layers or collected it as it dripped onto a rock, strip of bark or a piece of bark folded into a cup. The most tar gathered with this method, about 1.8 grams, was in a trial using a birch-bark cup placed beneath a bark roll with its lit side up and covered in embers.
Repeating either the ash-mound or pit-roll techniques once or twice would yield the relatively small quantity of tar found at one Neandertal site in Europe, the researchers say. Between six and 11 repetitions would produce a tar haul equal to that previously unearthed at another European site.
In a third technique, the scientists placed a birch-bark vessel for collecting tar into a small pit. They placed a layer of twigs across the top of the pit and placed pebbles on top, then added a large, loose bark roll covered in a dome-shaped coat of wet soil. A fire was then lit on the earthen structure. This method often failed to produce anything. But after some practice with the technique, one trial resulted in 15.7 grams of tar — enough to make a lump comparable in size to the largest chunks found at Neandertal sites.
An important key to making tar was reaching the right heat level. Temperatures inside bark rolls, vessels, fires and embers varied greatly, but at some point each procedure heated bark rolls to between around 200˚ and 400˚ Celsius, Kozowyk says. In that relatively broad temperature range, tar can be produced from birch bark, he contends.
If they exploited naturally occurring fires, Neandertal tar makers had limited time and probably relied on a simple technique such as ash mounds, Kozowyk proposes. If Neandertals knew how to start and maintain fires, they could have pursued more complex approaches.
Some researchers say that excavations point to sporadic use of fire by Neandertals, probably during warm, humid months when lightning strikes ignited wildfires. But other investigators contend that extinct Homo species, including Neandertals, built campfires (SN: 5/5/12, p. 18).
Whatever the case, Kozowyk says, “Neandertals could have invented tar with only basic knowledge of fire and birch bark.”
Planetary scientists now know how thick the Martian crust is, thanks to the strongest Marsquake ever observed.
On average, the crust is between 42 and 56 kilometers thick, researchers report in a paper to appear in Geophysical Research Letters. That’s roughly 70 percent thicker than the average continental crust on Earth.
The measurement was based on data from NASA’s InSight lander, a stationary seismometer that recorded waves rippling through Mars’ interior for four Earth years. Last May, the entire planet shook with a magnitude 4.7 quake that lasted more than six hours (SN: 5/13/22). “We were really fortunate that we got this quake,” says seismologist Doyeon Kim of ETH Zurich. InSight recorded seismic waves from the quake that circled Mars up to three times. That let Kim and colleagues infer the crust thickness over the whole planet.
Not only is the crust thicker than that of the Earth and the moon, but it’s also inconsistent across the Red Planet, the team found. And that might explain a known north-south elevation difference on Mars.
Topological and gravity data from Mars orbiters have shown that the planet’s northern hemisphere is substantially lower than the southern one. Researchers had suspected that density might play a part: Perhaps the rocks that make up northern Mars have a different density than those of southern Mars.
But the crust is thinner in the northern hemisphere, Kim and colleagues found, so the rocks in both hemispheres probably have the same average densities. That finding helps scientists narrow down the explanations for why the difference exists in the first place.
Knowing the crust’s depth, the team also calculated that much of Mars’ internal heat probably originates in the crust. Most of this heat comes from radioactive elements such as potassium, uranium and thorium. An estimated 50 to 70 percent of those elements are probably in the crust rather than the underlying mantle, computer simulations suggest. That supports the idea that parts of Mars still have volcanic activity, contrary to a long-held belief that the Red Planet is dead (SN: 11/3/22).
An ancient vegetarian dinosaur from the French countryside has given paleontologists something to sink their teeth into.
The most striking feature of a new species of rhabdodontid that lived from 84 million to 72 million years ago is its oversized, scissorslike teeth, paleontologist Pascal Godefroit, of the Royal Belgian Institute of Natural Sciences in Brussels, and his colleagues report October 26 in Scientific Reports. Compared with other dinos of its kind, Matheronodon provincialis’ teeth were at least twice as large but fewer in number. Some teeth reached up to 6 centimeters long, while others grew up to 5 centimeters wide. They looked like a caricature of normal rhabdodontid teeth, Godefroit says. Of hundreds of fossils unearthed over the last two decades at a site called Velaux-La Bastide Neuve in the French countryside, a handful of jaw bones and teeth now have been linked to this new species, Matheronodon provincialis. The toothy dino belongs to a group of herbivorous, bipedal dinosaurs common in the Cretaceous Period. Rhabdodontids sported bladelike teeth, and likely noshed on the tough woody tissue parts of plants. Palm trees, common in Europe at the time, might have been on the menu.
Rhabdodontid teeth have ridges covered by a thick layer of enamel on one side and little to no ridges or enamel on the other. Teeth in the upper jaw have more ridges and enamel on the outer edge, while the reverse is true for bottom teeth. A closer look at the microstructure of M. provincialis’ teeth revealed an exaggerated version of this — many more ridges and lopsided enamel coating. Enamel typically protects from wear and tear, so chewing would have sharpened the dino’s teeth. “They operated like self-sharpening serrated scissors,” Godefroit says.
Former Raiders receiver Henry Ruggs III has been ordered to appear in Las Vegas court on Monday following a missed alcohol test. That is a violation of his bond release restrictions following a fatal crash in which prosecutors say he was driving under the influence at 156 mph.
According to Clarke County court records, Ruggs missed one of four daily court-mandated alcohol tests at 4:41 p.m. local time on Saturday before completing "a client initiated remote breath test" at 6:28 p.m. the same day. The alcohol monitoring agency noted in court filings that it couldn't verify Ruggs' sobriety at the time he was supposed to complete his test earlier in the day. Ruggs' attorney David Chesnoff told Judge Suzan Baucum — who has ordered his reappearance in court — that the delay in his test was related to trouble with equipment provided to him. Ruggs, 22, could face a return to jail for violating the terms of his release. Ruggs was released on $150,000 bond on Wednesday, Nov. 3 and was ordered to remain on house arrest while undergoing electronic surveillance. He is also to refrain from alcohol or other controlled substances, among other restrictions.
Ruggs was arrested after his involvement in a fatal drunk-driving accident on Tuesday, Nov. 2. Prosecutors said he was driving 156 mph at the time of the crash, with a blood alcohol content level of .16 — twice the legal limit for Nevada drivers. Ruggs' Chevrolet Corvette struck the back of 23-year-old Tina Tintor's Toyota Rav4. Witnesses to the event indicated they tried to help Tintor and her dog escape the vehicle, but were ultimately forced back from flames emanating from the car. Ruggs faces two felony charges of DUI resulting in death or serious injury. That is considered a category B felony in Nevada, the second-worst violation of state law. The charges are non-probationary, meaning Ruggs will face jail time if convicted. Each charge carries a minimum two-year sentence, but can go as long as 20 years. He also faces two counts of felony reckless driving — charges with penalties of one to six years in prison — and a misdemeanor weapon charge.
The Raiders released Ruggs on Nov. 2 following his DUI arrest. He was the No. 12 overall pick in the 2020 NFL Draft, and the highest receiver taken in the draft.
Prior to the 2021-22 season, the NBA's historic 75th season, Stephen Curry was hot on the heels of Hall of Famer Ray Allen to become the all-time leader for most 3-pointers made.
Entering the season, Curry needed 142 3-pointers needed to surpass Allen, and 12 games into the season, he's knocked off 76 of the latter's lead. It's still early but Curry is averaging a career-high 5.4 makes per game, a shade above his previous career-high of 5.3 which he set last year in 63 games. During the 2015-16 season in which he set the all-time single-season record with 402 en route to winning his second straight MVP award, Curry averaged 5.1 makes in 79 games. Top 10 players on the all-time leader for most made 3-pointers Curry is one of three active players in the Top 10 with James Harden and Damian Lillard being the other two players.
Player 3-pointers
Ray Allen 2,973
Stephen Curry 2,908
Reggie Miller 2,560
James Harden 2,489
Kyle Korver 2,450
Vince Carter 2,290
Jason Terry 2,282
Jamal Crawford 2,221
Paul Pierce 2,143
Damian Lillard 2,087 LeBron James, who ranks 11th, could break into the Top 10 and increase the list to four active players later this season.
When will Stephen Curry surpass Ray Allen? Curry has hit 42 of the 76 3-pointers in just five games including a red-hot shooting game against the LA Clippers, where he erupted for 45 points that started with a perfect 25-point first quarter and an overall 8-of-13 efficiency from beyond the arc and a 50-piece against the Atlanta Hawks.
As of Nov. 16, the baby-faced assassin, who is considered to be the greatest 3-pointer shooter in NBA history, needs 76 more 3-pointers to overtake Allen. Going by his season average of 5.4 3-pointers per game, Curry would take anywhere around 14 games to jump to the No. 1 spot on the all-time charts.
That many games mean Curry could make NBA history in mid-December, provided of course that he misses no games moving forward.
Warriors upcoming 2021-22 schedule With that projection, Curry would likely make NBA history on the road as Golden State would be on a five-game Eastern Conference road trip in mid-December.
14 games ahead on the Warriors schedule will see the team in Indiana, the birthplace of basketball. 15 games ahead will see the Warriors at the iconic Madison Square Garden playing the Knicks.
In case Curry takes a couple more games to surpass Allen, he has a couple of more iconic locations awaiting him in Boston - home of one of the oldest franchises which is tied for the most champions in NBA history - and Toronto - the capital of the birth country of James Naismith, the sport's inventor.
Warriors upcoming schedule Date Opponent Time (ET) Nov. 10 vs. Timberwolves 10:00 pm Nov. 12 vs. Bulls 10:00 pm Nov. 14 at Hornets 7:00 pm Nov. 16 at Nets 7:30 pm Nov. 18 at Cavaliers 7:30 pm Nov. 19 at Pistons 7:00 pm Nov. 21 vs. Raptors 8:30 pm Nov. 24 vs. 76ers 10:00 pm Nov. 26 vs. Trail Blazers 10:00 pm Nov. 28 at LA Clippers 3:30 pm Nov. 30 at Suns 10:00 pm Dec. 3 vs. Suns 10:00 pm Dec. 4 vs. Spurs 8:30 pm Dec. 6 vs. Magic 10:00 pm Dec. 8 vs. Trail Blazers 10:00 pm Dec. 11 at 76ers 8:30 pm Dec. 13 at Pacers 7:00 pm Dec. 14 at Knicks 7:30 pm Dec. 17 at Celtics 7:30 pm
