Shock waves may have jolted the infant cosmos. Clumpiness in the density of the early universe piled up into traveling waves of abrupt density spikes, or shocks, like those that create a sonic boom, scientists say.

Although a subtle effect, the shock waves could help scientists explain how matter came to dominate antimatter in the universe. They also could reveal the origins of the magnetic fields that pervade the cosmos. One day, traces of these shocks, in the form of gravitational waves, may even be detectable.
Scientists believe that the early universe was lumpy — with some parts denser than others. These density ripples, known as perturbations, serve as the seeds of stars and galaxies. Now, scientists have added a new wrinkle to this picture. As the ripples rapidly evolved they became steeper, like waves swelling near the shore, until eventually creating shocks analogous to a breaking wave. As a shock passes through a region of the universe, the density changes abruptly, before settling back down to a more typical, slowly varying density. “Under the simplest and most conservative assumptions about the nature of the universe coming out of the Big Bang, these shocks would inevitably form,” says cosmologist Neil Turok of the Perimeter Institute for Theoretical Physics in Waterloo, Canada.

In a paper published September 21 in Physical Review Letters, Turok and Ue-Li Pen of the Canadian Institute for Theoretical Astrophysics in Toronto performed calculations and simulations that indicate shocks would form less than one ten-thousandth of a second after the Big Bang.

“It’s interesting that nobody’s actually noticed that before,” says cosmologist Kevork Abazajian of the University of California, Irvine. “It’s an important effect if it actually happened.”

These shocks, Turok and Pen found, could produce magnetic fields, potentially pointing to an answer to a cosmological puzzle. Magnetic fields permeate the Milky Way and other parts of the cosmos, but scientists don’t know whether they sprang up just after the birth of the universe or much later, after galaxies had formed. Shock waves could explain how fields might have formed early on. When two shocks collide, they create a swirling motion, sending electrically charged particles spiraling in a way that could generate magnetic fields.
Shocks could also play a role in explaining why the universe is made predominantly of matter. The Big Bang should have yielded equal amounts of matter and antimatter; how the cosmic scales were tipped in matter’s favor is still unexplained. Certain theorized processes could favor the production of matter, but it’s thought they could happen only if temperatures in the universe are uneven. Shocks would create abrupt temperature jumps that would allow such processes to occur.

Scientists may be able to verify these calculations by detecting the gravitational waves that would have been produced when shocks collided. Unfortunately, the gravitational ripples produced would likely be too small to detect with current technologies. But under certain theories, in which large density fluctuations create regions so dense that they would collapse into black holes, the gravitational waves from shocks would be detectable in the near future. “If there was anything peculiar in the early universe, you would actually be able to detect this with upcoming technology,” says Abazajian. “I think that is remarkable.”

Like many abandoned mines, the Eureka uranium mine in northern Spain is a maze of long, dank tunnels. Water seeping down the walls carries dissolved substances that percolated through rocks overhead. As the water evaporates into the tunnels’ cool air, some of those dissolved ingredients combine to make new substances in solid form.

“The mine is a crystallization factory of weird minerals,” says Jordi Ibáñez-Insa, a physicist at the Institute of Earth Sciences Jaume Almera in Barcelona.
Including the uranium-bearing ores that attracted miners to Eureka in the first place, scientists visiting the mine have cataloged 61 different minerals — solids that have a distinct chemical recipe and arrangement of atoms. The latest find, called abellaite, is a rarity that grows in small pincushions of tiny crystalline needles about 40 to 50 micrometers long. Discovered in July 2010, the mineral has been found only on the walls of a 3-meter-long stretch of one tunnel, says Ibáñez-Insa.

Abellaite is uncommon in another sense: It contains carbon. Of the 5,161 minerals characterized by scientists and recognized by the International Mineralogical Association, just 8 percent, or 416, include carbon.

The Carbon Mineral Challenge, launched last December and running until September 2019, exhorts researchers to scour the landscape — and their museum drawers — for unknown carbon-bearing minerals. In a recent analysis, scientists estimate that there are at least 548 carbon minerals on Earth. That means well over 100 are waiting to be noticed.

The analysis, published in the April American Mineralogist, even provides clues about where scientists and rock hounds should look and what recipes and atomic arrangements such minerals might have.
The hunt for carbon minerals is much more than stamp (or rock) collecting. The challenge aims to identify minerals that could help tell the story of the planet’s carbon and water cycles — past and present. Besides having a specific recipe and structure, minerals form only in certain conditions (on Earth and elsewhere), making them keen chroniclers of the environments that existed at the time and place they formed, as well as the conditions since then.

A census of minerals
A few minerals are, forgive the phrase, as common as dirt. Of the more than 5,000 recognized minerals, about 100 have been reported by geologists and amateur collectors at more than 1,000 sites worldwide. Many more are very rare: At least 1,000 minerals have been found in only one locale, says Robert Hazen, a geophysicist at the Carnegie Institution for Science in Washington, D.C. More than half of the world’s minerals have been found at five or fewer locations.

Not every mineral on Earth has been discovered, of course. But by analyzing a massive database of known minerals and how common or rare they are, scientists can use a standard statistical tool to estimate the number of minerals yet to be uncovered. Hazen and his colleagues suggest in the August 2015 issue of Mathematical Geosciences that there are at least 1,500 undiscovered minerals out there. About 140 of those minerals contain carbon, the team predicted in the follow-on analysis published in April.

Both professional mineralogists and amateur collectors can participate in the Carbon Mineral Challenge, but any potential discoveries have to survive the strict screening process of the International Mineralogical Association, which Ibáñez-Insa and a raft of colleagues navigated for abellaite. (The mineral was approved in December 2015.) The researchers submitted a portfolio of data — the sample’s appearance, chemical makeup, arrangement of atoms, color, hardness, transparency, fluorescence, a proposed name and more — to the IMA’s Commission on New Minerals, Nomenclature and Classification.

Promising places
In the search for hidden carbon-bearing minerals, scientists and rock hounds aspiring to geologic fame should visit these locales (or analyze samples already collected there).

Tap the map to explore carbon mineral “hot spots” around the world.
A few dozen new minerals are recognized each year, says Hans-Peter Schertl, a mineralogist at Ruhr University in Bochum, Germany, and an IMA officer. Approval can be straightforward, or it can drag out for months or longer, especially if additional data are required, Schertl says. One strict requirement is that a sample be natural, not lab-made or a result of human interference. Thus, any unusual crystals that grow on the surfaces of rocks that were pulled from a mine and then dumped nearby and exposed to the elements wouldn’t qualify as a mineral, he notes, “Those would just be pretty crystals.”

Oddly, the “natural sample” requirement long prevented official recognition of what is purported to be the most common mineral on Earth. Bridgmanite, an iron- and magnesium-rich silicate, received the IMA seal of approval only in 2014 (SN: 1/10/15, p. 4). Estimated to make up a whopping 38 percent of the planet’s volume, bridgmanite can exist only at the high pressures found between 660 and 2,900 kilometers below Earth’s surface — too deep to dig up. Scientists had long studied lab-made samples but hadn’t found a natural bit of the mineral until earlier this decade in a meteorite that landed in Australia in 1879.

Where to look
In their analysis published in April, Hazen and colleagues included general recipes for a variety of Earth’s yet-to-be-discovered carbon minerals. One formula — a complex mix of sodium, lead and carbonate and hydroxyl ions, written scientifically as NaPb2(CO3)2(OH) — matches abellaite from the Spanish mine. Bingo. One more carbon mineral in the bag.

Many of those “missing” minerals will be very similar to known forms, with combinations that differ by only a single element — swapping out a magnesium atom for a calcium atom in the recipe for a known mineral, for example, or a sodium atom for a potassium atom.

“The chemical formula tells you a lot about the conditions that a mineral forms in,” says Daniel Hummer, a geochemist at Southern Illinois University in Carbondale and lead scientist for the Carbon Mineral Challenge. It also suggests that existing minerals that have a very similar formula can, in many cases, serve as a guide for what the missing minerals might look like, in terms of the colors or shapes of their crystals.

In fact, similarities could be so strong that a mineral might be overlooked because it looks so much like a known, or even common, mineral. “It’s possible that some of these missing minerals are hiding in plain sight,” Hummer notes.

If not camouflaged, some carbon minerals may simply be so scarce that they’ve never been encountered. In June in American Mineralogist, Hazen and environmental scientist Jesse Ausubel of Rockefeller University in New York City discuss several reasons why minerals can be rare — so rare, in fact, that the entire world’s supply might fit into a thimble, Hazen says.

First, a mineral might form or remain stable only in extremely unusual combinations of temperature, pressure and pH. The mineral hatrurite (Ca3SiO5), for example, forms only at temperatures above 1,250° Celsius and only in the absence of aluminum, the third most common element in Earth’s crust. Hatrurite was first found in Israel, in an ancient limestone deposit that was probably exposed to intense heat generated when hydrocarbons in nearby sediments burned.

Second, a mineral might include chemical elements that are rare to begin with and even rarer in combination. Examples include swedenborgite (which contains the scarce combination of beryllium and antimony) and any mineral that includes tellurium, which on average is found in Earth’s crust at concentrations of 5 parts per billion.

Third, a mineral may be exceptionally ephemeral. Some are so hygroscopic, or humidity-absorbing, that they pull moisture from the air and dissolve themselves, Hazen says. Hygroscopic minerals have to be collected or observed in the field as they form and before they disappear. Then there are the minerals that form in conditions so remote or harsh that scientists hardly ever get near them (think deep-sea hydrothermal vents or active volcanoes).

Some minerals present more than one of these challenges. Consider fingerite, Cu11O2(VO4)6, an unstable shiny black mineral that forms only at high temperatures and includes the rare combination of copper and vanadium. This exceedingly rare mineral is known only from samples recovered from rocks near heat-belching fissures and holes atop El Salvador’s Izalco volcano.

There are less hostile places to search for new minerals, though. Fourteen sites worldwide, including mines, have each given up 20 or more carbon minerals, Hazen says. Scientists could revisit those 14 sites and look for more unrecognized minerals, he notes. Or they could simply take a closer look at or perform additional tests on samples already collected from such locales.
Or researchers could target areas where ephemeral minerals could be expected to form, if ever so briefly. For example, calcium carbide — a substance produced on an industrial scale to create acetylene for miner’s lamps — reacts so quickly with water that it hasn’t been found in a natural setting. But small, short-lived quantities might be produced when lightning strikes near rocks containing both limestone and coal (admittedly, a pretty hostile situation).

There’s no reason to be limited by the 14 promising locations. Scientists found the yellowish-white crystals of tinnunculite (C5H4N4O3•2H2O), mineral just recognized in December, in an unexpected milieu: inside the residue of bird poop that had landed on extremely hot rocks overlying an underground coal fire in northwestern Russia. The elevated temperatures drive the crystallization of uric acid in the excrement, the researchers say.

The exotic mineral was dubbed tinnunculite to honor the European kestrel (Falco tinnunculus), whose indispensable contribution to mineralogy cannot be denied.

For his part, Ibáñez-Insa plans to spend more time at Spain’s Eureka mine. Although the site’s uranium ores are no longer worth extracting, scientific treasures akin to abellaite may still lie undiscovered. “I’m pretty sure,” he says, “we’ll find some more new minerals there.”
This article appears in the October 15, 2016, issue of Science News with the headline, “Digging Carbon: A new challenge has scientists searching for dozens of unknown, beguiling crystals.”

When the body’s internal sense of time doesn’t match up with outside cues, people can suffer, and not just from a lack of sleep.

Such ailments are similar in a way to motion sickness — the queasiness caused when body sensations of movement don’t match the external world. So scientists propose calling time-related troubles, which can afflict time-zone hoppers and people who work at night, “circadian-time sickness.” This malady can be described, these scientists say, with a certain type of math.
The idea, to be published in Trends in Neurosciences, is “intriguing and thought-provoking,” says neuroscientist Samer Hattar of Johns Hopkins University. “They really came up with an interesting idea of how to explain the mismatch.”

Neuroscientist Raymond van Ee of Radboud University in the Netherlands and colleagues knew that many studies had turned up ill effects from an out-of-whack circadian clock. Depression, metabolic syndromes and memory troubles have been found alongside altered daily rhythms. But despite these results, scientists don’t have a good understanding of how body clocks work, van Ee says.

Van Ee and colleagues offer a new perspective by using a type of math called Bayesian inference to describe the circadian trouble. Bayesian inference can be used to describe how the brain makes and refines predictions about the world. This guesswork relies on the combination of previous knowledge and incoming sensory information (SN: 5/28/16, p. 18). In the case of circadian-time sickness, these two cues don’t match up, the researchers propose.

Some pacemaking nerve cells respond directly to light, allowing them to track the outside environment. Other pacemakers don’t respond to light but rely on internal signals instead. Working together, these two groups of nerve cells, without any supervision from a master clock, can set the body’s rhythms. But when the two timekeepers arrive at different conclusions, the conflict muddies the time readout in the body, leading to a confused state that could cause poor health outcomes, van Ee and colleagues argue.

This description of circadian-time sickness is notable for something it leaves out — sleep. While it’s true that shifted sleep cycles can cause trouble, a misalignment between internal and external signals may cause problems even when sleep is unaffected, the researchers suggest. That runs counter to the simple and appealing idea that out-of-sync rhythms cause sleep deprivation, which in turn affects the body and brain. That idea “was totally linear and beautiful,” Hattar says. “But once you start looking very carefully at the data in the field, you find inconsistencies that people ignored.”
It’s difficult to disentangle sleep from circadian misalignments, says neuroscientist Ilia Karatsoreos of Washington State University in Pullman. Still, research by him and others has turned up detrimental effects from misaligned circadian rhythms — even when sleep was normal. This new paper helps highlight why “it is important to be able to study and understand the contribution of each,” he says.

The concept of circadian-time sickness is an idea that awaits testing, Karatsoreos cautions. Yet it’s a “useful way for us to talk about this general problem, if only for the fact that it’s a way of thinking that I’ve really never seen before.”

Heating small patches of forest shows how climate warming might change the winner-loser dynamics as species struggle for control of prize territories. And such shifts in control could have wide-ranging effects on ecosystems.

The species are cavity-nesting ants in eastern North America. Normally, communities of these ant species go through frequent turnovers in control of nest sites. But as researchers heated enclosures to mimic increasingly severe climate warming, the control started shifting toward a few persistent winners. Several heat-loving species tended to stay in nests unusually long, instead of being replaced in faster ant upheavals, says Sarah Diamond of Case Western Reserve University in Cleveland.
That’s worrisome not only for the new perpetual losers among ants but for the ecosystem as a whole, she and her colleagues argue October 26 in Science Advances. Ants have an outsized effect on ecosystems. They churn up soil, shape the flow of nutrients and disperse seeds to new homes. Ant species that can’t compete in a warmer climate may blink out of the community array, with consequences for other species they affect.

Teasing out the indirect effects of climate change has been difficult. “We’ve all sort of thrown up our hands and said probably these interactions are quite important, but they’re really hard to measure so we’re just going to ignore that for now,” Diamond says.
Experiments have begun tackling those interactions, and the ant enclosures were among the most ambitious. At each of two experimental sites — in North Carolina and Massachusetts — researchers set up 15 roomy plots to mimic various warming scenarios, from 1.5 degrees Celsius above the surrounding air temperature to an extra 5.5 degrees C. To install outdoor heating, “we had backhoes in there digging trenches,” Diamond says. Giant propane tanks fueled boilers that forced warmer air into the enclosures to heat the soil. Computers monitored soil temperature and fine-tuned air flow.
At least 60 species of local ants came and went naturally, some of them nesting in boxes the researchers placed in the enclosures. For five years, the researchers regularly monitored which common species were living in the boxes.
Warmth gave an edge to a few heat-tolerant species such as Temnothorax longispinosus in the forest in Massachusetts. This tiny ant can build colonies inside an acorn and is a known target for attacks by slavemaker ants that invade nests instead of establishing their own. With increased warming, however, it and a few other heat-loving ants tended to hold their nests longer.

Those longer stints destabilize the ant community with its usual faster pace of turnovers of nests, which typically gives more species a chance at decent shelter and better luck in surviving in the community. What’s more, the analysis showed that the more a plot was heated, the more time the ants would need after some disturbance to return to the equilibrium of their usual affairs.

“A key strength of this study is their regular sampling,” says Jason Tylianakis, who holds joint appointments at the University of Canterbury in New Zealand and Imperial College London. Those data gave the scientists an unusually detailed picture of subtle community effects, he says.

The authors have “documented a new consequence of temperature change on communities,” says marine ecologist Sarah Gilman of the Claremont Colleges in California. Other studies have talked about climate change pushing communities to dramatically new, but ultimately stable states. But the ant experiment shows that climate change may be undermining the stability of communities that, at least for the moment, still look fairly normal.

Passing a kidney stone is not exactly rocket science, but it could get a boost from Space Mountain.

It seems that shaking, twisting and diving from on high could help small stones dislodge themselves from the kidney’s inner maze of tubules. Or so say two researchers who rode the Big Thunder Mountain Railroad roller coaster at Disney’s Magic Kingdom in Orlando, Fla., 20 times with a fake kidney tucked inside a backpack.

The researchers, from Michigan State University College of Osteopathic Medicine in East Lansing, planned the study after several of their patients returned from the theme park announcing they had passed a kidney stone. Finally, one patient reported passing three stones, each one after a ride on a roller coaster.
“Three consecutive rides, three stones — that was too much to ignore,” says David Wartinger, a kidney specialist who conducted the study with Marc Mitchell, his chief resident at the time.
Since neither of the two had kidney stones themselves, the pair 3-D printed a life-size plastic replica of the branching interior of a human kidney. Then they inserted three stones and human urine into the model. The stones were of the size that usually pass on their own, generally smaller in diameter than a grain of rice. After arriving at the park, Wartinger and Mitchell sought permission from guest services to do the research, fearing that two men with a backpack boarding the same ride over and over might strike workers as suspect.
“Luckily, the first person we talked to in an official capacity had just passed a kidney stone,” Wartinger says. “He told us he would help however we needed.”

Even when a stone is small, its journey through the urinary tract can be excruciating. In the United States alone, more than 1.6 million people each year experience kidney stones painful enough to send them to the emergency room. Larger stones — say, the size of a Tic Tac — can be treated with sound waves that break the stones into smaller pieces that can pass.

For the backpack kidney, the rear of the train was the place to be. About 64 percent of the stones in the model kidney cleared out after a spin in the rear car. Only about 17 percent passed after a single ride in the front car, the researchers report in the October Journal of the American Osteopathic Association.

Wartinger thinks that a coaster with more vibration and less heart-pounding speed would be better at coaxing a stone on its way.

The preliminary study doesn’t show whether real kidneys would yield their stones to Disney magic. Wartinger says a human study would be easy and inexpensive, but for now, it’s probably wise to check with a doctor before taking the plunge.

NEW ORLEANS — Marijuana use is associated with an almost doubled risk of developing stress cardiomyopathy, a sudden life-threatening weakening of the heart muscle, according to a new study. Cannabis fans may find the results surprising, since two-thirds believe the drug has no lasting health effects. But as more states approve recreational use, scientists say there’s a renewed urgency to learn about the drug’s effects.

An estimated 22 million Americans — including 38 percent of college students — say they regularly use marijuana. Previous research has raised cardiovascular concerns: The drug has been linked to an increased risk of heart attack immediately after use, and a 2016 study in rodents found that one minute of exposure to marijuana smoke impairs the heart’s inner lining for 90 minutes, longer than tobacco’s effect.

The new study, presented November 13 during the American Heart Association’s Scientific Sessions, examined the occurrence of stress cardiomyopathy, which temporarily damages the tip of the heart. Researchers from St. Luke’s University Health Network in Bethlehem, Pa., searched a nationwide hospital database and found more than 33,000 admissions for stress cardiomyopathy from 2003 to 2011. Of those, 210 were identified as marijuana users, and had about twice the odds of developing the condition, said Amitoj Singh, who led the study. Young men were at highest risk and more likely to go into cardiac arrest despite having fewer cardiovascular risk factors. Notably, the number of marijuana-linked cardiomyopathies increased every year, from 17 in 2007 to 76 in 2011. “With recent legalization, I think that’s going to go up,” Singh said.

Enhancing just three genes helps plants harvest more light, raising new hopes for developing crops that can keep up with food demands from a crowded planet.

Genetically engineered tobacco plants, chosen to test the concept, managed the unusual feat of growing 14 to 20 percent more mass — meaning more crop yield — than untweaked plants, says Krishna Niyogi of the University of California, Berkeley and Lawrence Berkeley National Laboratory. The gains came from inserting different versions of three genes that control how quickly plants ramp back up to full energy-harvesting capacity after going into a protective mode to protect themselves from too-bright sunlight, researchers report in the Nov. 18 Science.
Among results published so far, “to my knowledge, this is the first example where crop growth has been enhanced by improving photosynthesis,” says plant physiologist John Evans at Australian National University in Canberra, who wasn’t part of the new project.

Photosynthesis, the basic green chemistry for converting the sun’s energy into food, isn’t a perfectly efficient process (SN: 2/20/16, p. 12). And the quest to improve efficiency by manipulating the interlocking steps of more than 100 reactions in living crops has been complex. “We can make things worse, but this is the first time we can make something better,” Evans says.

The underlying idea for the tobacco experiment came from an appreciation of how light and shade dance over leaves throughout the day in a farm field. Sudden blasts of intense sunlight are dangerous stuff; an overload can lead to chemical scorching in a plant’s light-catching chloroplasts. So when the sun’s movement or a toss from a breeze suddenly exposes a chloroplast to more sunlight than it can handle, a protection system kicks in.
Enzymes in the leaf create a surge of a paprika-colored molecule called zeaxanthin, which helps offload the excess energy as heat. This protection turns on within minutes, but turns off more slowly when the crisis is over, Niyogi says.
Restoring full photosynthesis takes a lot more than just enhancing the back-to-normal mechanisms. An enzyme called ZEP dismantles protective zeaxanthin when it’s no longer needed. But making the plant simply build more ZEP keeps the protective system from turning on properly in the first place — which could put a plant at risk. So researchers also enhanced the enzyme called VDE that builds the protective zeaxanthin. With those two enzymes in balance, a chloroplast can still rid itself of excess energy but get back to full operations faster.
Enhancing a third protein, PsbS, also helped, although researchers don’t yet understand the full details of how. Tobacco plants with modified versions of all three proteins grew bigger, as measured by the weight of dried plant material, than others.

The extra growth those genes produced “is a major, economically important gain,” says Maureen Hanson of Cornell University, who is working on a different approach to improving photosynthesis. Now, she says, the new paper’s idea is ready for attempted transfer to plants that people harvest for grains or fruits. Hanson is hopeful that size will increase there, too.

Coaxing plants to calm down faster after a crisis is just one strategy to make photosynthesis more efficient. Evans and Hanson are among those involved in efforts to improve a notoriously slow and distractible photosynthetic enzyme called Rubisco (SN Online: 9/19/14). Other researchers are trying to transfer a naturally more efficient photosynthetic system found in some tropical and subtropical plants, called C4 photosynthesis, into rice, one of the world’s main grains.

Older strategies for wringing more food from farms are not on track to keep up with soaring human population and food demands, Niyogi says. The United Nation’s Food and Agriculture Organization has estimated that feeding the world in 2050 could require boosting food production by an additional 70 percent. But the success of all of this, Niyogi notes, may depend on how people around the world feel about genetically engineered food.

Scanning a fetus’s genome just a few weeks after conception may soon be an option for expecting parents. Mom just needs to get a Pap smear first.

By scraping a woman’s cervix as early as five weeks into a pregnancy, researchers can collect enough fetal cells to test for abnormalities linked to more than 6,000 genetic disorders, researchers report November 2 in Science Translational Medicine. It’s not clear exactly how fetal cells make their way down to the cervix, says study coauthor Sascha Drewlo of Wayne State University School of Medicine in Detroit. But the cells may invade mom’s mucus-secreting glands, and then get washed into the cervical canal.

Current prenatal tests include amniocentesis and chorionic villus sampling, but they work later in pregnancy: at least 12 weeks for amnio and at least nine weeks for CVS. Amnio requires a long needle threaded through a pregnant woman’s belly and uterus; CVS often does, too. Instead, Drewlo’s team gathered fetal trophoblast cells, which give rise to the placenta, and were able to examine the genomes of 20 fetuses.

The new technique, which can work with as few as 125 fetal cells, could one day help physicians care for their tiniest patients. For some genetic conditions, such as congenital adrenal hyperplasia, early detection means mom can take some medicine to “actually treat the fetus in utero,” Drewlo says.

Nuts about Neandertals
Recent genetic analyses of populations around the world showed that a wave of ancient humans left Africa about 50,000 to 72,000 years ago. All non-Africans alive today originated from this single wave, Tina Hesman Saey reported in “One Africa exodus populated globe” (SN: 10/15/16, p. 6).

“If the Neandertals were already present when Homo sapiens arrived on the scene, from whence did the N­eandertals originate, and how did they get there ahead of the (true) humans?” Peter Goodwin asked.
“Neandertals didn’t race ahead of humans out of Africa,” Saey says. Some earlier ancestor of both modern humans and Neandertals migrated out of the continent long before either species came on the scene. “Neandertals evolved outside of Africa, possibly from Homo heidelbergensis. They ‘grew up’ in Europe and Southwest Asia and were already present when humans started to venture out of Africa” she says.

But once human ancestors ventured into new territories, they met up and mated with Neandertals and other hominids, Bruce Bower says. Scientists are studying physical changes in the bodies of various animal hybrids to understand signs of this ancient interbreeding, Bower reported in “The hybrid factor” (SN: 10/15/16, p. 22).

Online reader Mark S. wondered if hybridization could explain the similarities between even older hominids like Homo naledi and Australopithecus, which have collarbones and finger bones in common (SN: 5/14/16, p. 12).

Biological anthropologist Rebecca Ackermann of the University of Cape Town in South Africa suspects hybridization helped shape the a­natomy of H. naledi and other ancient hominid species, Bower says. But no DNA has been extracted from H. naledi fossils to explore that possibility. DNA from Spanish fo­ssils does suggest that Neandertals and Denisovans may have interbred more than 430,000 years ago (SN Online: 3/14/16).
Quantum leap through time
Researchers teleported quantum particles over long distances in Canada and China. The feats could lay the groundwork for a quantum internet, Emily Conover reported in “New steps toward quantum internet” (SN: 10/15/16, p. 13).

“Is there any chance that quantum communication could send messages to the past or future … information time travel?” online reader J Ferris asked.

“Unfortunately, quantum mechanics does not allow faster-than-light c­ommunication — although it seems like it could at first blush,” Conover says. Through entanglement, quantum particles appear to remotely affect one another instantaneously. But to transmit or receive actual information, other details about the me­asurement must be sent through normal light-speed channels. “That’s a good thing,” she says. “If faster-than-light communication were possible, communication back in time would be too, which would cause all kinds of weird paradoxes. You could talk to your parents before you were born and perhaps convince them not to have children.”

Failure to launch
A star that vanished in 2009 may be the first confirmed case of a failed supernova. A faint infrared light and a black hole are all that remain of NGC 6946, Christopher Crockett reported in “Lost star may be failed supernova” (SN: 10/15/16, p. 8).

Jan Steinman wondered if the star’s collapse released enough gravitational energy for scientists to detect it using the Advanced Laser Interferometer Gravitational-Wave Observatory, or LIGO, which confirmed the existence of gravitational waves earlier this year.

Failed supernovas indeed produce gravitational waves detectable by LIGO, Crockett says. However, the waves are generated at the heart of stellar explosions, regardless of whether or not those explosions “fail” and collapse into black holes. It would be difficult to tell the difference between a supernova and a failed one from the gravitational waves alone, says Fermilab’s James Annis.

For centuries, stargazers have known which star was Polaris and which was Sirius, but those designations were by unofficial tradition. The International Astronomical Union, arbiter of naming things in space, has now blessed the monikers of 227 stars in our galaxy. As of November 24, names such as Polaris (the North Star) and Betelgeuse (the bright red star in Orion) are approved.

Until now, there has been no central star registry or guidelines for naming. There are many star catalogs, each one designating stars with different combinations of letters and numbers. That excess of options has left most stars with an abundance of labels (HD 8890 is one of over 40 designations for Polaris).

The tangle of titles won’t disappear, but the new IAU catalog is a stab at formalizing the more popular names. Before this, only 14 stars (included in the 227) had been formally named, as part of the IAU’s contest to name notable exoplanets and the stars that they orbit (SN: 2/6/16, p. 5). One famous star is returning to its ancient roots. The brightest member of Alpha Centauri, the pair of stars that are among the closest to our solar system, is now officially dubbed Rigil Kentaurus, an early Arabic name meaning “foot of the centaur.”