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Scientists Are Freaking Out Over The First-Ever Footage of This Bizarre Squid - ScienceAlert
Ram's horn shells are small, delicate spiral structures beachcombers can commonly find throughout the world.
Ram's horn shells are small, delicate spiral structures beachcombers can commonly find throughout the world. Yet despite their ubiquity, the original owners of these shells are extremely elusive. Until now, we've never had footage of a single one in the wild. In the twilight zone of our oceans, at the tips of sunlight's fingers, a remotely operated vehicle (ROV) has now delivered the first footage of a ram's horn squid (Spirula spirula) in its natural habitat. This strange-looking cephalopod is a wee little thing barely 7 centimetres (under 3 inches) in length, with eight arms, two tentacles, a pair of bulging eyes, and a general muppet-like appearance. In its tail-end, hidden beneath its mantle, is a tightly-coiled internal shell equipped with chambers of gas that the animal manipulates for buoyancy. At first, researchers operating the ROV at the Schmidt Ocean Institute had no idea what they were looking at. "What on Earth?" a scientist can be heard exclaiming in the background of the video, which was shot live on the Great Barrier Reef at a depth of roughly 850 to 860 metres (2,790 ft). Exciting news! This appears to be the FIRST observation of Spirula, aka ram's horn squid, alive + in its natural environment. Very rarely seen or captured, they have many extinct relatives, but are only living member of genus Spirula, family Spirulidae, and order Spirulida. 1/3 pic.twitter.com/re4rZyRuER Schmidt Ocean (@SchmidtOcean) October 27, 2020 The rare sighting has since been shared online and confirmed to be the first footage of a live Spirula in the deep sea, the largest and least explored habitat on our planet. While there are numerous deep-sea species never before seen in their natural waters, this recent chance encounter has got scientists especially excited. OMG! Ok, I don't want to get too excited...but according to several squid experts, this may be the FIRST VIDEO OF A LIVE RAM HORN SQUID! While these squid have many extinct relatives, they're the only ones left of thier kind & have a spiraling [email protected]#DailyJellypic.twitter.com/0Lv6ESvYNI Open Ocean Exploration (@RebeccaRHelm) October 27, 2020 The ram's horn squid is rarely seen in the wild, and it's one of the most unusual cephalopods out there. Apart from cuttlefish, it's the only other known mollusc that contains an internal chambered shell to keep it buoyant. Yet unlike cuttlefish, this squid's skeleton is tightly coiled; molluscs in the Nautilus genus also have similarly-shaped shells, but they go on the outside of the animal. "I've been looking for these for a long time," zoologist Michael Vecchione, who studies midwater squid at the Smithsonian National Museum of Natural History, told ScienceAlert. "I have no question at all it's a Spirula." While Vecchione regularly catches this species from the deep, sometimes housing them in aquariums, he's never before seen footage of the squid in its natural habitat. Neither has Neige Pascal, who studies Spirula at the University of Burgundy in France. He told ScienceAlert the video is "very exciting". Spirula shell. (Antonov/Public Domain) Apart from the sheer rarity of this encounter, there's one particularly surprising aspect in the footage: the very position of the animal, with its head and tentacles floating upright, and its fins pointing down. "Are we completely sure about the orientation of the shoot? If this is the case, this is a king of revolution," Pascal told ScienceAlert. "A lot of people are freaking out because the head is up," adds Vecchione. "And the reason they're freaking out is because the shell with its buoyancy is at the other end of the squid. So you'd think the head, which is heavier, would be hanging down." When put in an aquarium, this is actually how the squid orients. Its head faces down and its tentacles face up - so the species was thought to take the same position in the deep sea. (Ewald Rübsamen/Public Domain) According to Vecchione, however, there's a problem with that assumption. Ram's horn squid also have a light-generating organ, known as a photophore, which is located near the buoyant shell. This means if Spirula are hanging with their head down, that light would be facing upwards, and that's highly unusual for deep-sea animals. In the twilight zone of our oceans, predators often have their eyes looking up in the hopes of glimpsing the silhouette of a possible meal. Hence photophores help disguise prey in the deep sea by washing out their silhouettes with light. If that lamp is pointing upwards, that organ isn't nearly as useful. There's a lot we still don't know about Spirula, including how the species reproduces and where it lays its eggs, but the way this squid orients itself in the water is one of the biggest questions for Vecchione. While he can't be sure it floats with its tentacles always facing upwards, he says the footage is good evidence the squid does this at least part of the time. We'll need more observations to solve that mystery. And the curiosities surrounding the ram's horn squid don't end there. When the creature at last dashed away in the video, it looks as though a bit of ink spilled into the water; Vecchione is pretty sure that came from the squid - a possible diversion tactic for its escape. Possible inking from Spirula spirula. (Schmidt Ocean Institute/YouTube) "That's interesting because Spirula has the mechanism to make ink but it's reduced in this species, like other deep-sea species," Vecchione told ScienceAlert. "But this suggests it's functional and they're using it for defence." It might be our first time spotting a ram's horn squid in its natural habitat, but it's also their first time in the face of a leering ROV. Fair enough if they wet themselves.
Giant Asteroid Survivor of Failed Planet Discovered to Be Slowly Rusting in Space - ScienceAlert
Roughly two to three times Earth's distance from the Sun, in the Asteroid Belt that lies between Mars and Jupiter, 16 Psyche makes its home. This giant metal asteroid is one of the most massive objects in the Asteroid Belt, categorised as a minor pla
Roughly two to three times Earth's distance from the Sun, in the Asteroid Belt that lies between Mars and Jupiter, 16 Psyche makes its home. This giant metal asteroid is one of the most massive objects in the Asteroid Belt, categorised as a minor planet. Astronomers think that 16 Psyche is the exposed core of a full planet that didn't make it all the way, and we're itching to know more about it. NASA will be sending a probe to check it out in the next few years, and in the meantime, scientists are working to glean what they can from Earth. Now, for the first time, 16 Psyche has been studied in ultraviolet wavelengths using the Hubble Space Telescope, revealing that, just as we thought, the dense chunk of space rock is remarkably metallic. "We've seen meteorites that are mostly metal, but Psyche could be unique in that it might be an asteroid that is totally made of iron and nickel," said planetary scientist Tracy Becker of the Southwest Research Institute. "Earth has a metal core, a mantle and crust. It's possible that as a Psyche protoplanet was forming, it was struck by another object in our Solar System and lost its mantle and crust." 16 Psyche is a pretty fascinating chunk of rock. It's about 226 kilometres (140 miles) across, and just a little less dense than Earth. Its composition seems to consist of somewhere between 30 to 60 percent metal, and the rest low-iron silicate. If 16 Psyche is a protoplanetary core, it's possible such impacts stripped it of its accumulating material. Planets are thought to form when their stars are very young - possibly even in tandem - and are surrounded by a thick cloud of dust and gas. Material in this cloud starts to stick together, first electrostatically, then gravitationally as the object grows more massive. As these bodies grow, they become hot and a bit molten, allowing material to move around. Core differentiation is the process whereby denser material sinks inwards towards the centre of the object, and less dense material rises outwards. For 16 Psyche to be a differentiated core, the protoplanet would once have had to have been much bigger than it is now. Exactly when, and how, its outer mantle was stripped away is a bit of a head-scratcher. But Becker's team's research could be the breadcrumbs that put us on the trail to figuring it out. "We were able to identify for the first time on any asteroid what we think are iron oxide ultraviolet absorption bands," she said. "This is an indication that oxidation is happening on the asteroid, which could be a result of the solar wind hitting the surface." In other words, 16 Psyche is rusting. And we might be able to work out how old its surface is based on how much oxidation has occurred - which in turn could give us a timeline of when the asteroid was stripped of its outer material. The asteroid's high reflectivity at ultraviolet wavelengths suggests that it's been a long time; usually, ultraviolet brightness is linked with space weathering. But we won't know for sure until NASA's Psyche probe reaches the asteroid sometime around 2026. Scientists are also keen to get a closer look at 16 Psyche's composition. There's a lot of wiggle room between 30 and 60 percent metal that has made it hard to track down smaller pieces of rock that may have resulted from the impact fragmentation of the 16 Psyche's mantle. It was once thought that the relatively metallic mesosiderite meteorites were remnants of 16 Psyche, but more recent research has found the connection weak. The work of Becker and her team revealed a spectrum that is consistent with pure iron, but that may be misleading - as little as 10 percent iron on the surface could dominate the ultraviolet spectrum. There are also very few analogous observations of planetary surfaces in ultraviolet against which to compare the new views of 16 Psyche. So, we obviously just have to go and check it out with an actual orbiting probe, which in turn will indicate how well we've done trying to figure out this strange object from hundreds of millions of kilometres away. Whatever we learn, it's going to be like looking at a Solar System time capsule. "What makes Psyche and the other asteroids so interesting is that they're considered to be the building blocks of the Solar System," Becker said. "To understand what really makes up a planet and to potentially see the inside of a planet is fascinating. Once we get to Psyche, we're really going to understand if that's the case, even if it doesn't turn out as we expect. Any time there's a surprise, it's always exciting." The research has been published in The Planetary Science Journal.
Astronomers Peer Into The Atmosphere of a Rare Exoplanet That 'Shouldn't Exist' - ScienceAlert
The discovery of the extraordinary exoplanet LTT 9779b was first announced a month ago. Just 260 light-years away, the planet was immediately pegged as an excellent candidate for follow-up study of its curious atmosphere. But it turns out we didn't
The discovery of the extraordinary exoplanet LTT 9779b was first announced a month ago. Just 260 light-years away, the planet was immediately pegged as an excellent candidate for follow-up study of its curious atmosphere. But it turns out we didn't even have to wait too long to learn more. LTT 9779b is a little bigger than Neptune, orbiting a Sun-like star - fairly normal so far. But two things are really peculiar. It's so close to its star, the planet orbits once every 19 hours; and, in spite of the scorching heat it must be subjected to at that proximity, LTT 9779b still has a substantial atmosphere. Infrared observations collected by the now-retired Spitzer Space Telescope included the planet's host star, and astronomers have now analysed those data, publishing their results in a couple of studies. In the first paper, a team led by astronomer Ian Crossfield of the University of Kansas has described LTT 9779b's temperature profile. In the second paper, a team led by astronomer Diana Dragomir of the University of New Mexico has characterised the exoplanet's atmosphere. "For the first time, we measured the light coming from this planet that shouldn't exist," Crossfield said. "This planet is so intensely irradiated by its star that its temperature is over 3,000 degrees Fahrenheit [1,650 degrees Celsius] and its atmosphere could have evaporated entirely. Yet, our Spitzer observations show us its atmosphere via the infrared light the planet emits." An exoplanet phase curve. (ESA) He and his team studied the exoplanet's phase curve in infrared light. Here's what that means: Because thermal energy is emitted as infrared radiation, light in this wavelength can tell us the temperature of cosmic objects many light-years away. The system is oriented in such a way that the planet passes between us and the star, giving us clear broadside views of both the planet's night and day sides. Thus, to calculate the exoplanet's temperature, astronomers can use the changing light of the overall system as LTT 9779b orbits. Interestingly, the hottest time of day for LTT 9779b is just about bang on noon, when its sun is directly overhead. On Earth, the hottest time of day is actually a few hours after noon, because heat enters Earth's atmosphere faster than it is radiated back out into space. In turn, this allows for some educated guesses about the atmosphere of LTT 9779b. "The planet is much cooler than we expected, which suggests that it is reflecting away much of the incident starlight that hits it, presumably due to dayside clouds," said astronomer Nicolas Cowan of the Institute for Research on Exoplanets (iREx) and McGill University in Canada. "The planet also doesn't transport much heat to its nightside, but we think we understand that: The starlight that is absorbed is likely absorbed high in the atmosphere, from whence the energy is quickly radiated back to space." To further probe the atmosphere of LTT 9779b, Dragomir and her colleagues focused on secondary eclipses, when the planet passes behind the star. This results in a fainter dimming of the system's light than when the planet passes in front of the star - known as a transit - but that fainter dimming can help us understand the thermal structure of an exoplanet's atmosphere. "Hot Neptunes are rare, and one in such an extreme environment as this one is difficult to explain because its mass isn't large enough to hold on to an atmosphere for very long," Dragomir said. "So how did it manage? LTT 9779b had us scratching our heads, but the fact that it has an atmosphere gives us a rare way to investigate this type of planet, so we decided to probe it with another telescope." The researchers combined Spitzer secondary eclipse data with data from NASA's exoplanet-hunting space telescope TESS. This allowed them to obtain an emission spectrum from LTT 9779b's atmosphere; that is, the wavelengths of light absorbed and amplified by elements therein. They found that some wavelengths were being absorbed by molecules - probably carbon monoxide. This is not unexpected for such a hot planet. Carbon monoxide has been detected in hot Jupiters - gas giants that also orbit their stars at scorchingly close proximity. But gas giants are more massive than hot Neptunes, and use their much higher gravity to retain their atmospheres. It was thought that Neptune-sized planets should not be massive enough to do so. Finding carbon monoxide in the atmosphere of a hot Neptune could help us understand how this planet formed, and why it still has its atmosphere. So, while we know more about LTT 9779b than we did, there's still work to be done. Future observations could help us answer these questions and others, such as what else is the atmosphere made of, and did the exoplanet start off much larger, and is currently in the process of rapidly shrinking. Research like this will give us an excellent toolkit and experience for probing the atmospheres of potentially habitable worlds, too. "If anyone is going to believe what astronomers say about finding signs of life or oxygen on other worlds, we're going to have to show we can actually do it right on the easy stuff first," Crossfield said. "In that sense these bigger, hotter planets like LTT 9779b act like training wheels and show that we actually know what we're doing and can get everything right." The two papers have been published in The Astrophysical Journal Letters, here and here.
Extreme 'Black Widow' Star Identified as Source of Mystery Gamma Radiation - ScienceAlert
For more than two decades, astronomers have been systematically tracing mystery sources of high-energy gamma rays to their sources.
For more than two decades, astronomers have been systematically tracing mystery sources of high-energy gamma rays to their sources. One, however, remained stubborn - the brightest unidentified source of gamma rays in the Milky Way. It seemed to be coming from a binary system 2,740 light-years away, but only one of the stars could be found. Now, astronomers have solved the mystery and pinned down that second star by searching gamma-ray data obtained between 2008 and 2018. Together, the two stars constitute one of the weirdest binary systems we've ever seen. "The binary star system and the neutron star at its heart, now known as PSR J1653-0158, set new records," said astronomer Lars Nieder of the Albert Einstein Institute Hannover in Germany. "We have discovered the galactic dance of a super heavyweight with a flyweight: At slightly more than twice the mass of our Sun, the neutron star is extraordinarily heavy. Its companion has about six times the density of lead, but only about 1 percent the mass of our Sun. "This 'odd couple' orbits every 75 minutes, more quickly than all known comparable binaries." It's been thought since at least 2009 that the gamma radiation detected from the system must be produced by a gamma-ray pulsar. Then, in 2014, X-ray and optical observations of the source of the gamma rays turned up a variable star with a 75-minute period. This was the tiny companion star, and astronomers thought that the 75-minute period was consistent with an orbital period with the second star being the source of the gamma rays. "But all searches for the neutron star in it have so far been in vain," said astronomer Colin Clark of the Jodrell Bank Centre for Astrophysics at the University of Manchester in the UK. The second star was thought to be a pulsar. That's a type of rapidly rotating neutron star that beams radiation from its poles as it spins. Those beams are a little like a lighthouse, flashing (or pulsing) past the observer at the rate of the star's rotation. Radio pulsars are more usual, but gamma-ray pulsars are known too. In order to confirm the presence of the second star, you'd need to find the pulsations in time with its rotation. So the team went hard. They crunched a decade's worth of gamma-ray data collected by the Large Area Telescope (LAT) on board NASA's Fermi Gamma-ray Space Telescope, using computing power donated by tens of thousands of members of the citizen science program [email protected] In just two weeks, they found their pulsar. It's a bit of an oddball. The pulsar is rotating extremely fast, more than 500 times a second. Millisecond pulsars do rotate extremely fast; that's what accounts for the "millisecond" part of their name. But PSR J1653-0158 has one of the fastest rotation rates ever seen in pulsars. In addition, the star has an extremely weak magnetic field. It's within the bottom three ever detected for pulsar magnetic field strength. The companion is also quite strange, since it has incredibly low mass. The team believes it's a helium white dwarf that's been cannibalised by the pulsar, leaving behind a remnant. This kind of system is known as a 'black widow' binary. "The remnant of a dwarf star orbits the pulsar at just 1.3 times the Earth-Moon distance in only 75 minutes at a speed of more than 700 kilometres per second (435 miles per second)," Nieder said. "This unusual duo might have originated from an extremely close binary system, in which matter originally flowed from the companion star onto the neutron star, increasing its mass and causing it to rotate faster and faster while simultaneously dampening its magnetic field." (Knispel/Clark/Max Planck Institute for Gravitational Physics/NASA) Above: Visualisation of the system (bottom) compared to Earth and the Moon (top). This hypothesis is supported by the team's search for radio waves. If the pulsar is emitting any, we can't detect them; this could be because the system is surrounded by a dense cloud of material from the cannibalised dwarf star. Gamma radiation could penetrate this cloud, but not radio waves. Either way, PSR J1653-0158 is only the second millisecond pulsar found that's not emitting any detectable radio waves. "In binary systems like the one we have now discovered, pulsars are known as 'black widows' because, like spiders of the same name, they eat their partners, so to speak," Clark said. "The pulsar vaporises its companion with its radiation and a particle wind, filling the star system with plasma that is impenetrable to radio waves." That we find the system so peculiar may be because of the limitations of technology. With tools like [email protected], which essentially uses idle computing time to provide supercomputing capabilities, we may be at the cusp of a new era of pulsar discovery. "In the catalogue of gamma-ray sources found by the Fermi satellite, there are dozens more that I would bet have binary pulsars in them," said astronomer Bruce Allen of the Max Planck Institute for Gravitational Physics in Hannover and Director and founder of [email protected] "But so far no one has been able to detect the characteristic pulsation of their gamma rays. With [email protected], we hope to do just that - who knows what other surprises await us." The research has been published in The Astrophysical Journal Letters.
These Tiny, Little-Winged Dinosaurs Were Probably Worse at Flying Than Chickens - ScienceAlert
The discovery of two small dinosaurs with bat-like wings a few years ago was a palaeontologist's dream. Just how flight evolved in birds is something we're still trying to nail down, and looking at this early evolution of bat-like wings in dinosaurs
The discovery of two small dinosaurs with bat-like wings a few years ago was a palaeontologist's dream. Just how flight evolved in birds is something we're still trying to nail down, and looking at this early evolution of bat-like wings in dinosaurs could give us a clue. But a team of researchers has now pointed out that just because you have wings, it doesn't necessarily mean you're actually any good at flying. Yi qi and Ambopteryx longibrachiumare two species of theropod dinosaurs that lived around 160 million years ago, both of which had unusually elongated fingers, and a skin membrane stretching between them, similar to a bat's wing. This is an entirely different kind of wing to the one theropod dinosaurs evolved to fly with the dinosaurs that eventually became birds. And, unlike them, after only a few million years, Yi and Ambopteryx became extinct, which is the first hint that these unusual wings could not match those birds-to-be. However, weird wings on extinct critters mean it's likely multiple types of wings (and therefore flight) evolved over the years, and that Yi and Ambopteryx'sattempts were not the winning strategy. But before you can write off Yi and Ambopteryx as complete evolutionary flight failures, you have to know how good (or bad, as the case may be) the two species were at flight. In 2015, when Yi was found, that team of researchers suggested that the size of its wings and other flight characteristics could mean it was a gliding creature however it's unlike any other glider we know of, and its centre of mass might have made even gliding difficult. We just weren't sure. A new study, by researchers in the US and China, has now looked into the flight potential of Yi and Ambopteryx in a lot more detail, and come to the conclusion that they really weren't good at getting their little feet off the trees they lived in. "Using laser-stimulated fluorescence imaging, we re-evaluate their anatomy and perform aerodynamic calculations covering flight potential, other wing-based behaviours, and gliding capabilities," the team writes. "We find that Yi and Ambopteryx were likely arboreal, highly unlikely to have any form of powered flight, and had significant deficiencies in flapping-based locomotion and limited gliding abilities." The team's analysis of the fossils (Yi pictured below) was able to pick up tiny details in soft-tissue that you can't see with normal light. Fossil of Yi qi. Look how fluffy it is! (kmkmks/Flickr/CC BY SA 2.0) Then the team modelled how the dinosaurs might have flown, adjusting for things such as weight, wingspan, and muscle placement (all stuff we can't tell just from the fossils). The results were underwhelming. "They really can't do powered flight," says first author, biologist Thomas Dececchi from Mount Marty University. "You have to give them extremely generous assumptions in how they can flap their wings. You basically have to model them as the biggest bat, make them the lightest weight, make them flap as fast as a really fast bird, and give them muscles higher than they were likely to have had to cross that threshold. They could glide, but even their gliding wasn't great." Soft-tissue map of Yi qi. (Dececchi et al., iScience, 2020) So, according to Dececchi and his team's model, we're looking at flying capabilities considerably worse than a chicken, perhaps worse than the flightless New Zealand parrot, the kakapo, which is also mostly limited to gliding from trees, but can at least flap to control descent. But although it's a bit sad for the Yi and Ambopteryx, it's good news for us the findings give even more evidence that dinosaurs evolved flight (or at least tried to) multiple times. As the team points out, considering all the types of bats, gliders, flying squirrels, and other gliding or flying mammals, maybe it shouldn't be a surprise. "We propose that this clade was an independent colonisation of the aerial realm for non-avialan theropods. If true, this would represent at least two, but more likely three or more attempts at flight (both powered and gliding) by small pennaraptoran theropods during the Mesozoic," the team writes in their paper. "Given the large number of independent occurrences of gliding flight within crown mammals, this should perhaps be unsurprising, but it does create a more complex picture of the aerial ecosystem." Seems like some things don't change much, even in a hundred million years. The research has been published in iScience.
Monkeys May Have Self-Domesticated Just Like Humans Did, Study Suggests - ScienceAlert
Monkeys, much like humans, could be engaged in the process of self-domesticating themselves, altering the course of their own evolution and physiology through the way they behave with one another, new research suggests.
Monkeys, much like humans, could be engaged in the process of self-domesticating themselves, altering the course of their own evolution and physiology through the way they behave with one another, new research suggests. It's long been recognised that domestication in animals promotes certain physical features that aren't observed in their wild counterparts. This phenomenon called domestication syndrome has been noted since the era of Charles Darwin and is thought to lie behind all sorts of physical traits and characteristics. While the term 'domestication' is perhaps most often used in the context of humans domesticating animals, it doesn't always mean that. Scientists also hypothesise that humans unwittingly self-domesticated ourselves opting for partners exhibiting less aggressive and more social behaviours. The thinking is that, over generations, those choices may have bred out some of the more wild and animalistic aspects of our ancient demeanour, promoting tolerance and prosocial conduct instead, which in turn could have led to the development of human civilisation as we know it. It seems a convincing argument, but scientists acknowledge that evidence for this hypothesis remains largely circumstantial. "It's really a popular and exciting idea but one that lacks direct evidence, a link between friendly behaviour and other features of domestication," says neuroscientist Asif Ghazanfar from Princeton University. Thanks to Ghazanfar and his team's new research, though, we might have identified such a link. In experiments with marmoset monkeys (Callithrix jacchus), the researchers found what they claim to be the first data showing an association between vocal social behaviour in an animal species and a physical domestication trait in individual animals. Marmosets exhibit a high degree of social tolerance and pro-sociality and communicate with one another by taking turns vocalising. In previous research, Ghazanfar and his team showed that infant monkeys learn these vocalisations in a similar way to how babies learn to speak, via social reinforcement from their parents. This kind of parental feedback has effects on more than just vocalisation technique, however. One of the known markers of domestication in marmosets is a depigmentation trait: a prominent white patch of fur on the animals' foreheads. Common marmoset with a white patch on the forehead. (mb-fotos/Getty Images) The researchers wanted to investigate whether there was a link between the vocal exchanges and this particular morphological feature, which, if it were found, could be taken as evidence of a form of self-domestication. In experiments with three pairs of infant twins from three different marmoset families, each of the infant monkeys was given vocal feedback from a 'simulated parent': a computer designed to sound like an adult responding to their own calls. However, in these sessions, conducted over two months, one of the twins in each pair was given 10 times more vocal feedback than its sibling. The researchers found that the amount of vocal training the animals received was linked to the size of the white patch of fur on their head, with the marker of domestication appearing bigger and growing quicker if they received more talk time. "If you change the rate of the marmosets' vocal development, then you change the rate of fur colouration," Ghazanfar says. "It's both a fascinating and strange set of results!" The researchers suggest that this phenomenon is due to neural crest cells, a form of stem cell that migrates throughout the body during early development. One of the derivatives of neural crest cells is melanocytes that contribute to pigmentation, and the researchers contend that the simple act of experiencing more vocal training acts as a kind of self-domestication conditioning that affects the young marmoset's developing body. There's much to still explore about how neural crest cells may be involved in these processes, and the researchers acknowledge their study is small and in want of future replication in separate research. Nonetheless, it is that rare thing: experimental evidence of how interaction within a species looks to be associated with self-domestication a breakthrough that might help spur additional discoveries. "The potential involvement of neural crest cells provides a mechanism by which behavioural experience can be linked to the emergence of morphological phenotypes associated with domestication," the researchers write. "This in turn provides new insights into how selection on correlated phenotypes may have acted during human evolution, as hominins became increasingly reliant on cooperative networks for survival and reproduction." The findings are reported in Current Biology.
The BepiColombo Probe Just Took a Ridiculously Close Video of Venus as It Flew By - ScienceAlert
Two years after it left Earth, Mercury probe BepiColombo has completed the first of its first flybys of Venus. The manoeuvre is designed to give the spacecraft a boost on its journey - but it's also too good an opportunity to pass up for a little sci
Two years after it left Earth, Mercury probe BepiColombo has completed the first of its first flybys of Venus. The manoeuvre is designed to give the spacecraft a boost on its journey - but it's also too good an opportunity to pass up for a little science. As it swung around the planet on a curved trajectory, BepiColombo gave its instruments a workout, testing their functionality for a taste of what the spacecraft will do in Mercury orbit and collecting some data on Venus recently in the news for the discovery of phosphine gas in its atmosphere. And the joint European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA) probe took a whole lot of images, which the ESA compiled into a video of the flyby. "This sequence of 64 images was captured by Monitoring Camera 2 onboard the Mercury Transfer Module from 40 minutes before until 15 minutes after closest approach of 10,720 kilometres (6,661 miles) from Venus," wrote the ESA in a blog post. "The images were taken every 52 seconds." The images had to be slightly processed - Venus was so bright that the images are quite saturated, even with the shortest exposure times. But the shape of the terminator line, which marks the boundary between night and day, changes as BepiColombo moves around the planet in a curved trajectory. (ESA/BepiColombo/MTM) Gravity assist manoeuvres are a very common tool for moving spacecraft around the Solar System. They're also the work of very careful planning, with a route painstakingly mapped out in advance, with forward projection of where planets and moons are going to be when the spacecraft reaches them, in order to make the most of the encounters a voyaging spacecraft is going to have. Basically, gravity assists use the gravity of a planet to aid the spacecraft in its journey, altering its trajectory and speed either giving it a slingshot forwards, or helping it slow down. BepiColombo's journey involves nine gravity assists. The first involved Earth on April 10, earlier this year. Venus was the second, taking place on October 15, using the planet's gravity to slow the spacecraft down without expending fuel. The third will also be Venus, in August 2021; the remaining six gravity assist flybys will be of Mercury itself, further slowing BepiColombo down so that it can finally arrive in a stable orbit in December 2025. Both Venus flybys will be used to test BepiColombo instruments and collect Venus data. In this first flyby, scientists with the German Aerospace Center (DLR) and the University of Münster in Germany fired up the MErcury Radiometer and Thermal Infrared Spectrometer (MERTIS) instrument to take almost 100,000 images as BepiColombo approached the planet. "During the Earth flyby, we studied the Moon, characterising MERTIS in flight for the first time under real experimental conditions. We achieved good results," said MERTIS project manager Gisbert Peter of the DLR Institute of Optical Sensor Systems. "Now we are pointing MERTIS towards a planet for the first time. This will allow us to make comparisons with measurements taken prior to the launch of BepiColombo, to optimise operation and data processing, and to gain experience for the design of future experiments." Venus and Mercury are quite different from one another - Mercury's a naked ball of dense rock and metal, and Venus is shrouded in a thick, toxic atmosphere that keeps the planet's surface temperature at scorching levels. MERTIS was designed to collect data on the rock composition of Venus, but its infrared capabilities can also penetrate Venus' clouds to a certain depth. MERTIS won't be able to detect the phosphine that so intrigued the world. But one theory about the phosphine was that it was created by volcanic activity. And recent evidence suggests that volcanic activity may be ongoing on Venus; this is something MERTIS can investigate. "These [volcanoes] would be detected, for example, through the sulphur dioxide that they emit," said planetary scientist Jörn Helbert from the DLR Institute of Planetary Research. "Following the first measurements made in the 1960s and 1970s, about ten years ago, ESA's Venus Express mission recorded a massive reduction, by more than half, of sulphur dioxide concentrations. Venus literally 'smells' of active volcanoes! MERTIS could now provide us with new information." We won't have that information for a little while yet. The newly collected data will have to make its way down the processing and analysis pipeline. But it's so exciting, being on the cusp of a new era of Solar System science. And, although it's not BepiColombo's main mission, it's really exciting having a different, newer set of tools to poke into Venus' mysteries. "We are already expecting some very interesting findings, with more to follow in 2021, when we will be much closer to Venus," said planetary scientist Harald Hiesinger of the University of Münster.
For The First Time, Astronomers See Plumes of Sulfur Dioxide From The Volcanoes of Io - ScienceAlert
For the first time, astronomers have seen clear evidence of plumes of toxic volcanic gas erupting forth from the volcanoes of Io.
For the first time, astronomers have seen clear evidence of plumes of toxic volcanic gas erupting forth from the volcanoes of Io. New radio images of the Jovian moon have finally provided some answers to long-standing questions about its atmosphere. Io is the most volcanic place in the Solar System. More than 400 active volcanoes speckle its surface, the manifestation of the moon's internal stress as it is gravitationally tugged in different directions not just by Jupiter but by the planet's other three Galilean moons. Io's thin atmosphere and surface are dominated by sulfur dioxide - yes, brimstone - belched from the interior. It spews out as a gas through volcanic splits and maws and settles on the ground at night as it cools, giving the moon its sickly yellow and orange hues. But just how much of that gas directly comes from volcanoes, versus how much comes from frozen surface sulfur dioxide re-heated in sunlight? That has been difficult to quantify. "It was not known which process drives the dynamics in Io's atmosphere," said astronomer Imke de Pater of the University of California, Berkeley. "Is it volcanic activity, or gas that sublimates from the icy surface when Io is in sunlight? What we show is that, actually, volcanoes do have a large impact on the atmosphere." Researchers finally have some answers, and at the same time have been able to detect plumes of volcanic sulfur dioxide on the moon. Io in infrared!taken by the JIRAM instrument aboard @NASAJuno spacecraft.#Juno#Io#JIRAM#Infraredpic.twitter.com/zO94xqkACI Roman Tkachenko (@_RomanTkachenko) April 10, 2018 For a world that's constantly leaking volcanic gas, Io's atmosphere is surprisingly thin; most of gas therein escapes through a complex interaction with Jupiter and its magnetic field at a rate of around 1 metric ton per second, contributing to a colossal doughnut of plasma called the Io plasma torus that orbits Jupiter. The remaining atmosphere can reveal a lot about the geological processes in the moon's interior, which in turn could help us understand some of the dynamics of planets beyond our Solar System. If we know precisely the effects of the competing gravitational influences on Io, and why those influences don't have the same effect on other bodies, we can make more educated inferences on how gravitational influences affect exoplanets too far away to see well. So, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to take a closer look at Io under radio wavelengths as it moves in and out of Jupiter's shadow - a Jovian eclipse. The first thing they found is that sulfur dioxide does not stay in Io's atmosphere. At night, the temperature drops below sulfur dioxide's freezing point. When that surface reemerges into daylight, the frozen sulfur dioxide sublimates back into the atmosphere, replenishing it in about 10 minutes - much quicker than expected. This strange quirk turned out to be the perfect tool for studying the volcanic atmospheric contribution. "When Io passes into Jupiter's shadow, and is out of direct sunlight, it is too cold for sulfur dioxide gas, and it condenses onto Io's surface," explained astronomer Statia Luszcz-Cook from Columbia University. "During that time we can only see volcanically-sourced sulfur dioxide. We can therefore see exactly how much of the atmosphere is impacted by volcanic activity." In the ALMA images, the team was able to clearly identify, for the first time, evidence of plumes of sulfur dioxide and sulfur monoxide emitting from volcanic sources. In volcanic regions with no sulfur dioxide or monoxide, they saw something else - potassium chloride, another volcanic gas. This suggests that different volcanoes are tapping into different magma reservoirs, rather than sharing them. This suggests some interesting complexity beneath the surface of Io. True-colour image of Io taken by the Galileo spacecraft. (NASA/JPL/University of Arizona) From their images, the team was able to calculate the volcanic contribution to Io's atmosphere. Around 30 to 50 percent of the sulfur dioxide comes directly from volcanoes. Obviously future work will help narrow that down. The team says that the next step in their research is trying to take the temperature of Io's atmosphere, particularly at low altitudes. This will be somewhat more challenging, but not impossible. "To measure the temperature of Io's atmosphere, we need to obtain a higher resolution in our observations, which requires that we observe the moon for a longer period of time. We can only do this when Io is in sunlight, since it does not spend much time in eclipse," de Pater said. "During such an observation, Io will rotate by tens of degrees. We will need to apply software that helps us make unsmeared images. We have done this previously with radio images of Jupiter made with ALMA and the Very Large Array." The research is available in two papers, one published in The Planetary Science Journal, and the other in press with The Planetary Science Journal and uploaded to arXiv.
The First Star in Our Galaxy Caught Sending Out Fast Radio Bursts Is Doing It Again - ScienceAlert
A little dead star that dazzled us earlier this year is not done with its shenanigans.
A little dead star that dazzled us earlier this year is not done with its shenanigans. Magnetar SGR 1935+2154, which in April emitted the first known fast radio burst from inside the Milky Way, has flared up once more, giving astronomers yet another chance to solve more than one major cosmic mystery. On 8 October 2020, the CHIME/FRB collaboration detected SGR 1935+2154 emitting three millisecond radio bursts in three seconds. Following up on the CHIME/FRB detection, the FAST radio telescope found something else - a pulsed radio emission consistent with the magnetar's spin period. "It's really exciting to see SGR 1935+2154 back again, and I'm optimistic that as we study these bursts more carefully, it will help us better understand the potential relationship between magnetars and fast radio bursts," astronomer Deborah Good of the University of British Columbia in Canada, and member of the CHIME/FRB, told ScienceAlert. The detections, reported in The Astronomer's Telegram, are currently undergoing analysis. Before April of this year, fast radio bursts (FRBs) had only ever been detected coming from outside the galaxy, usually from sources millions of light-years away. The first one was discovered in 2007, and ever since, astronomers have been trying to figure out what causes them. As the name implies, FRBs are bursts of extremely powerful radio waves detected in the sky, some discharging more energy than hundreds of millions of Suns. They last mere milliseconds. Because most fast radio burst sources seem to flare once and haven't been detected repeating, they're extremely unpredictable. In addition, the ones we've detected usually come from so far away, our telescopes are unable to pick out individual stars. Both of these characteristics make FRBs challenging to track down either to an exact source galaxy, or a known cause. But SGR 1935+2154 is only around 30,000 light-years away. On 28 April 2020, it spat out a powerful millisecond-duration burst, which has since been named FRB 200428 in keeping with fast radio burst naming conventions. Once the power of the signal was corrected for distance, FRB 200428 was found to be not quite as powerful as extragalactic fast radio bursts - but everything else about it fit the profile. "If the same signal came from a nearby galaxy, like one of the nearby typical FRB galaxies, it would look like an FRB to us," astronomer Shrinivas Kulkarni of Caltech told ScienceAlert in May. "Something like this has never been seen before." We don't know much about the three new bursts yet. Because scientists are still working on the data, it's possible that some early conclusions are likely to change, Good told ScienceAlert. But we can already tell that they are both like and unlike FRB 200428. They are a little less powerful again, but they are all still incredibly strong, and all just milliseconds long. "Although less bright than the detection earlier this year, these are still very bright bursts which we'd see if they were extragalactic," Good said. "One of the most interesting aspects of this detection is that our three bursts seem to have occurred within one rotation period. The magnetar is known to rotate once every ~3.24 seconds, but our first and second bursts were separated by 0.954 seconds, and the second and third were separated by 1.949 seconds. That's a bit unusual, and I think it's something that we'll be looking into further going forward." That could reveal something new and useful about magnetar behaviour, because - let's face it - they are pretty weird. Magnetars - of which we have only confirmed 24 to date - are a type of neutron star; that's the collapsed core of a dead star not massive enough to turn into a black hole. Neutron stars are small and dense, about 20 kilometres (12 miles) in diameter, with a maximum mass of about two Suns. But magnetars add something else to the mix: a shockingly powerful magnetic field. These jaw-dropping fields are around a quadrillion times more powerful than Earth's magnetic field, and a thousand times more powerful than that of a normal neutron star. And we still don't fully understand how they got that way. But we do know that magnetars undergo periods of activity. As gravity tries to keep the star together - an inward force - the magnetic field, pulling outward, is so powerful, it distorts the star's shape. This leads to ongoing tension which occasionally produces gargantuan starquakes and giant magnetar flares. SGR 1935+2154 has been undergoing such activity, suggesting a link between magnetar tantrums and at least some FRBs. Obviously, astronomers have found the source of the first intra-galactic FRB to be of intense interest. When CHIME/FRB reported their detection, other astronomers went to have a look at the star, including a team led by Zhu Weiwei of the National Astronomical Observatories of China who had access to FAST, the largest single-aperture radio telescope in the world. And they found something interesting, also reported in The Astronomer's Telegram - pulsed radio emission. These radio pulses were nowhere near as strong as the bursts, but they're extremely rare: If validated, SGR 1935+2154 will only be the sixth magnetar with pulsed radio emission. And the pulse period was found to be 3.24781 seconds - almost exactly the star's spin period. This is curious, because so far, astronomers have struggled to find a link between magnetars and radio pulsars. Pulsars are another type of neutron star; they have a more normal magnetic field, but they pulse in radio waves as they spin, and astronomers have long tried to figure out how the two types of stars are related. Earlier this year, Australian astronomers identified a magnetar that was behaving like a radio pulsar - a possible "missing link" between the two, and evidence that at least some magnetars could evolve into pulsars. SGR 1935+2154 could be another piece of the puzzle. "Based on these results and the increasing bursting activities, we speculate that the magnetar may be in the process of turning into an active radio pulsar," Weiwei's team wrote. What an absolutely bloody fascinating little star this is turning out to be.
The Closest Black Hole to Earth May Not Actually Be a Black Hole After All - ScienceAlert
An object identified earlier this year as the closest black hole we've ever discovered may have just been demoted. After reanalysing the data, separate teams of scientists have concluded that the system in question, named HR 6819, does not include a
An object identified earlier this year as the closest black hole we've ever discovered may have just been demoted. After reanalysing the data, separate teams of scientists have concluded that the system in question, named HR 6819, does not include a black hole after all. Instead, they have found that it's likely just two stars with a slightly unusual binary orbit that makes it difficult to interpret. HR 6819, located around 1,120 light-years away, has been a bit of a puzzle for some time. Initially, it was thought to be a single star of the Be spectral type. This is a hot, blue-white star on the main sequence whose spectrum contains a strong hydrogen emission line, interpreted as evidence of a disc of circumstellar gas ejected by the star as it rotates at an equatorial velocity of around 200 kilometres per second. In the 1980s, astronomers noticed that the object seemed also to be exhibiting the light signature of a second type of B-type star, a B3 III star. This was found in 2003 to mean that HR 6819 was not one, but two stars, although they could not be individually resolved. Further analysis revealed that the B3 III star, clocking in at an estimated 6 solar masses, had a roughly 40-day orbit - but the Be star, also estimated to be around 6 solar masses, seemed to be motionless. If the two stars comprised an equal mass binary, they should orbit a mutual centre of gravity, not one star orbiting the other. After conducting careful calculations, a team of astronomers concluded that the B3 III star could be orbiting another, third object, one that couldn't be seen. A black hole. But, other astronomers argue, that's far from the only possibility. What if we have miscalculated the masses of the stars? "The presence of a Be star component in the spectrum of HR 6819 suggests another interpretation of the system," wrote astronomers Douglas Gies and Luqian Wang of Georgia State University in their paper. "It is possible that the B3 III stellar component is actually a low mass, stripped down star that is still relatively young and luminous. In this case, the Be star would be the companion in the 40-day binary instead of a black hole." In other words, the much lower-mass B3 III star would whizz around the Be star. If this were the case, that orbital motion could be detectable in the hydrogen gas surrounding the Be star - it would move almost imperceptibly as it was tugged by the smaller star. This is what Gies and Wang went looking for. They carefully studied the hydrogen emission in the system's spectrum, and found that the hydrogen disc around the Be star did indeed display a 40-day periodicity in both Doppler shift and emission line shape. This is consistent with the B3 III star's orbit - just as would be expected if the system were an unequal-mass binary. "This indicates," they wrote, "that HR 6819 is a binary system consisting of a massive Be star and a low-mass companion that is the stripped down remnant of a former mass donor star in a mass transfer binary." In other words, the Be star slurped up a whole bunch of material from the B3 III star, leaving it much smaller. There is, the team noted, recent evidence that suggests many Be stars are the product of this process. According to their calculations, the Be star would be about 6 solar masses, as previously found; but the B3 III star would be between 0.4 and 0.8 solar masses. But it gets more interesting. Gies and Wang were not the only researchers looking into this idea. In a second paper, a team of astronomers led by Julia Bodensteiner of KU Leuven in Belgium independently examined the hydrogen emission of the Be star, and performed an orbital analysis of the system. She and her colleagues came to almost exactly the same conclusion. "We infer spectroscopic masses of 0.4 [solar masses] and 6 [solar masses] for the primary and secondary," they wrote in their paper. "This indicates that the primary might be a stripped star rather than a B-type giant. Evolutionary modelling suggests that a possible progenitor system would be a tight B+B binary system that experienced conservative mass transfer In the framework of this interpretation, HR 6819 does not contain a BH." And, in a third paper, currently in preprint, astronomers Kareem El-Badry and Eliot Quataert of UC Berkeley also independently analysed the system's spectra, obtaining masses of 0.47 and 6.7 solar masses for the B3 III and Be stars respectively. "We argue that the B star is a bloated, recently stripped helium star with mass 0.5 solar masses that is currently contracting to become a hot subdwarf," El-Badry and Quataert wrote. "The orbital motion of the Be star obviates the need for a black hole to explain the B star's motion. A stripped-star model reproduces the observed luminosity of the system, while a normal star with the B star's temperature and gravity would be more than 10 times too luminous." So the future looks grim for the black hole interpretation, although it's not settled quite yet. Future observations could help resolve any lingering questions. But, Gies and Lang argue, the binary system could be more interesting than a black hole. "The luminous and low-mass companion in the HR 6819 system may represent a rare and important case in which the companion has recently completed mass transfer and has yet to descend to the white dwarf cooling stage of evolution," they wrote. So, either way, we have not yet heard the last from HR 6819. Gies and Lang's research was published in The Astrophysical Journal Letters. Bodensteiner et al.'s research was published in Astronomy & Astrophysics. El-Badry and Quataert's paper has been submitted to the Monthly Notices of the Royal Astronomical Society and is available on arXiv.