Leonardo da Vinci ‘Relics’ Discovered That Can Potentially Provide His DNA

An illustration of Leonardo da Vinci's presumed remains in Amboise, France.

Italian researchers say that they have found two “relics” belonging to Leonardo da Vinci, which may help in sourcing the DNA of the genius whose work typified the Renaissance.

The mysterious relics were traced during a decades-long genealogical study into Leonardo's family.

Historian Agnese Sabato and Alessandro Vezzosi, director of the Museo Ideale in Vinci, will announce their findings on Thursday at a conference in the Tuscan town of Vinci, where the artist was born in 1452.

“I can’t yet disclose the nature of these relics,” Vezzosi told Seeker. “I can only say that both are historically associated with Leonardo da Vinci. One is an object, the other is organic material.”

If genuine, the organic relic would represent Leonardo’s only known biological evidence.

It was believed that no traces were left of the painter, engineer, mathematician, philosopher and naturalist. The remains of Leonardo, who died in 1519 at the age of 67 in Amboise, France, are known to have been dispersed before the 19th century.

But in 1863 a skeleton and large skull were found at the site of the church of Saint-Florentin, where Leonardo was originally interred, which was plundered in the 16th century during religious wars and completely destroyed in 1808.

A stone inscription was unearthed near the skeleton. It read LEO DUS VINC, pointing to Leonardo's name.

The bones attributed to Leonardo went lost for a decade. They were rediscovered in 1874 and reburied in the chapel of Saint-Hubert at the Château d'Amboise. There, a plaque correctly states that the grave contains Leonardo's “presumed remains.”

Permission to exhume the bones for analysis has always been denied for ethical reasons. The organic relic claimed by the researchers was sourced from an unidentified private collector.

“We have verified its historical accuracy, and we can now say the relic is associated to the skeleton unearthed in 1863,” Sabato said.

Vezzosi and Sabato, who have founded an organization called Leonardo da Vinci Heritage to safeguard and promote his legacy, have been searching for biological traces of Leonardo since 2000. They began by scrutinizing the master’s paintings and manuscripts for his fingerprints.

“We pieced together an archive of hundreds of Leonardo’s fingerprints, hoping to get some biological material,” Vezzosi said. “At that time, cracking da Vinci’s DNA code was just a wild dream. Now it’s a real possibility.”

A crucial twist in the research occurred last year, when Vezzosi and Sabato announced the existence of dozens of Leonardo’s living descendants at a crowded conference in Vinci.

“It has been a long and exhausting research, as we had to deal with repeating names and confusing da Vinci and Vinci surnames,” Vezzosi said.

Leonardo was the illegitimate son of Ser Piero da Vinci, a Florentine legal notary, and Caterina, an enigmatic woman described in documents as being “the wife of Achattabriga di Piero del Vaccha da Vinci." He had a sprawling family that included four stepmothers and as many as 24 half-brothers and half-sisters.

Since last year, Vezzosi and Sabato have updated the official da Vinci family tree, adding more than 150 names.

“The hunt for Leonardo DNA can now rely on a good, well-referenced genealogy,” Sabato told Seeker.

She explained that all of the direct descendants come from Leonardo’s father Ser Piero, since Caterina's relatives appear to be lost in history.

“But we are working to track them down,” Sabato said. “We discovered that one of Caterina’s daughters had three daughters, so we are searching in this direction.”

Finding Caterina’s descendants — living or dead — might help in retrieving Leonardo’s mitochondrial DNA, which is passed down through the maternal line.

The researchers are now conferring with several international universities to begin a broader scientific investigation on the relics and Leonardo’s descendants. They plan to carry out DNA analysis on the relic and compare it to Leonardo’s newly discovered living descendants and to bones found in recently identified da Vinci burials throughout Tuscany.

The study is part of a wider project to find Leonardo’s DNA by 2019, to mark the 500th anniversary of his death.

“Overall, we have more than promising material to continue our research and isolate da Vinci’s DNA, 15 generations later,” Vezzosi said.

Even if it won’t be possible to retrieve any usable DNA from the relic, Leonardo’s reconstructed family tree still leaves hope to track down his Y chromosome.

Vezzosi and Sabato have found a direct and uninterrupted line which runs from Leonardo's half-brother Domenico Matteo to living male descendants.

Read more at Discovery News

New Fossil Carnivore May Explain Why Our Primate Relatives Stayed in Trees

The skull of a hyaenodont.

A new and very toothy fossil carnivore has just been discovered in Egypt, and corresponding research could help to explain why our early primate relatives tried to spend as much time as possible in trees.

The meat lover has been named Masrasector nananubis, after the canine-headed Egyptian god Anubis, who was associated with the afterlife. Unearthed at a site called “Locality 41” in Egypt’s Fayum Depression, located west of the Nile and south of Cairo, the new fossil is described in the journal PLOS ONE.

“We found that M. nananubis had limbs most like a fast-moving, ground based carnivore, similar to a fox or mongoose,” lead author Matthew Borths, who co-authored the paper with Erik Seiffert, told Seeker. “It likely hunted by stalking its prey on the ground, or by waiting in ambush in the dense foliage of the forested Fayum for small prey to scamper by.”

The researchers determined that the Anubis namesake lived 34 million years ago and was a hyaenodont. Borths, a researcher at Ohio University’s department of biomedical sciences, and Seiffert, a professor in the department of integrative anatomical sciences at the University of Southern California, explained that hyaenodonts were the top predators in Africa after the extinction of the dinosaurs.

Fayum Depression of Egypt where the fossils for Masrasector nananubis were found.

“Despite their name, hyaenodonts are not closely related to hyenas,” Borths continued. “The name means they had hyena-like teeth, which is true. Like hyenas, hyaenodonts were meat eaters and some were bone crackers.”

What’s more, they found that M. nananubis belongs to a lineage of hyaenodonts called the teratodontines, which means “monstrous teeth.” Based on other fossils discovered at Locality 41, this carnivore lived alongside even larger hyaenodonts, such as the coyote-sized Brychotherium and the wolf-sized Akhnatenavus. Large snakes and crocodiles also existed at the site.

“The environment they all lived in 34 million years ago was a marshy forest, reminiscent of parts of the Everglades or the Louisiana gulf coast, which makes sense because geologists hypothesize the coast was close to the site where these fossils were preserved,” Borths said.

He added that some localities at the site “include fossils of large fruits and trees, evidence this forested habitat would have also been appealing to our early primate relatives.”

It's little wonder that our early relatives tried to spend as much time as possible in trees, given the tasty food above ground and the hungry, blood-thirsty carnivores on the ground. The researchers said that some hyaenodonts did evolve to become tree-dwellling, which could have made life all the more interesting for our primate ancestors.

Life reconstruction of Hyaenodon, a relative of Masrasector nananubis.

The impressive teeth of M. nananubis — which featured both meat-slicing, blade-like teeth and teeth designed for grinding — suggest that this carnivore could forage on fruits and seeds, in addition to consuming meaty flesh.

Hyaenodonts over time spread out of Africa and into Europe, Asia and North America. They were once a very successful and widespread bunch, and yet, as far as researchers know, they all died out and left no descendants. Their extinction remains a mystery.

Read more at Discovery News

Ancient Sea Scorpion's Weaponized Tail Made Mincemeat of Our Aquatic Ancestors

Illustration of the sea scorpion Slimonia acuminata attacking an early vertebrate.

Long before the evolution of sharks and barracudas, some of the scariest predators lurking in the primordial seas were eurypterids, better known as sea scorpions. Related to modern scorpions and horseshoe crabs, these animals included species that had sharp pinching claws and the ability to crawl out of water to hunt on land. They thrived around 430 million years ago, with certain species growing to over 10 feet long.

A newly discovered, well-preserved fossil eurypterid adds a weapon to the known arsenal of these ancient formidable predators: a slapping, slashing tail spine. Its wielder, Slimonia acuminata, represents a new species of eurypterid that once even feasted on our early fish ancestors. It is described in the journal The American Naturalist.

“Slimonia would have lurked in the shallow waters of lagoons and lakes along the coast of primordial Europe, during the Silurian Period (443.7–416 million years ago),” lead author Scott Persons, of the University of Alberta’s Department of Biological Sciences, told Seeker. “At the time, our vertebrate ancestors were primitive fish.”

Persons and co-author John Acorn studied Slimonia’s remains, which were unearthed at the Patrick Burn Formation near Lesmahagow, Scotland. This sea scorpion was not one of the largest eurypterids, given that it measured about a foot and a half long. Its weaponized tail gave it an edge over most other predators, though.

Slimonia acuminata fossil.

One specimen preserves the sea scorpion’s serrated and spine-tipped tail, curved strongly to one side. The tail actually consists of two attached parts: a rounded area that looks a bit like an arrowhead, and then the actual knife-like spine. The researchers suspect that the former might have served double duty as a rudder when Slimonia was swimming.

As for how this predator dispatched prey, Persons said that Slimonia probably used its chelicerae, or segmented mouth parts, to hold onto our ancestors and other victims, “while repeatedly striking with sidelong blows from the tail spine.”

Unlike today’s lobsters and shrimps, which can flip their broad tails up and down to help them swim, sea scorpion tails were vertically inflexible but horizontally highly mobile. A cool feature was that they could aggressively slap and slash sideways, while still meeting a minimum of hydraulic resistance. This helped to prevent them from propelling themselves away from an intended target with each forceful strike.

The other top ocean predators at the time were enormous cephalopods, meaning the relatives of modern squid, octopus and the chambered nautilus.

“These were real Lovecraftian monsters, with sharp beaks and lots of tentacles,” Persons explained, referring to the horror fiction of H. P. Lovecraft.

The giant squid surely feasted on our ancient ancestors, but also probably took on Slimonia from time to time.

Close-up of the weaponized tail of Slimonia acuminata.

“A soft cephalopod body would not have wanted to get struck by Slimonia’s tail, but we know that octopus are capable of handling lots of spiky dangerous prey by dexterously immobilizing them with the strong tentacles,” Persons said.

He added that, unlike sea scorpions, whose fossilized shells reveal their full body size and shape, the remains of ancient cephalopods require more scientific guesswork. That's because their soft bodies do not easily fossilize.

Clues to their existence are cephalopod shells, some of which were spiral shaped, like a snail’s, while others were swirl shaped, Persons said, “like a tall helping of soft-serve ice cream.”

“Of the swirl-shelled Silurian cephalopods — say that five times fast — a few grew to well over a meter (3.3 feet) in length,” he continued. “Like modern squid, they could have reached out with their tentacles, snagged a victim and then pulled it back into their mouths.”

Read more at Discovery News

Despite Debate, Estimates of Humanity’s Impact on Climate Change Are Accurate

Climate change contrarians have used many arguments to cast doubt on the scientific consensus that the atmosphere is warming and humans are to blame.

They’ve alleged that tens of thousands of scientists, working across dozens of different disciplines, have organized a vast conspiracy to manipulate data. They’ve said more carbon dioxide in the atmosphere will actually be a benefit because it will boost agricultural production. And they’ve even said that global warming has paused in recent years.

But their primary tactic these days appears to be to acknowledge that the concentration of greenhouse gases in the atmosphere is increasing due to human causes, but suggest that the scientific community just can’t pin down what impact those emissions will have on the climate system.

Trump’s EPA administrator Scott Pruitt made that claim during his Senate confirmation hearing, as did former ExxonMobil CEO turned Secretary of State Rex Tillerson.

Kyle Armour of the University of Washington, writing in Nature Climate Change, says that, actually, the scientific community has done quite well at developing accurate predictions of how sensitive the atmosphere and oceans are to carbon pollution.

The debate, he says, pivots around a number called equilibrium climate sensitivity (ECS), which is the temperature change that scientists expect to occur with a doubling of carbon dioxide in the atmosphere compared to before the Industrial Revolution.

“This is the number that’s been essentially at the heart of climate change predictions for decades now,” he said. “It has a lot of policy relevance. If this number is high, we have a very sensitive Earth that will warm up a lot in response to greenhouse gases. If the number is low, we have a less sensitive climate system that would warm up a lot less.”

Put another way, climate sensitivity tells us how we need to limit greenhouse gas emissions in order to stay well below an average global temperature increase of 2°C compared to the mid-19th century, which many scientists say is a dangerous threshold to pass.

The problem is observations collected over the past 100 years have shown the climate to be less sensitive to increasing greenhouse gas concentrations than computer models of the climate have predicted.

And that’s where Armour got to work.

“It appeared that newer observations suggested a fairly low climate sensitivity in the range of about 2°C for a doubling of CO2, whereas the models suggested a higher climate sensitivity more in the range of 3°C for a doubling of CO2,” he said. “What I was interested in with the study was basically how much of the discrepancy between the observations and the models could be explained by the fact that climate sensitivity changes over time.”

There’s an incredible amount of inertia built into Earth’s climate system. The increased amount of energy trapped in the atmosphere due to all of the greenhouse gas emissions from our coal-fired power plants and internal combustion engines takes many decades to fully take effect.

And the climate system works in complex ways. When rising air temperatures in the Arctic melt summer sea ice, for example, it creates larger areas of dark, open ocean which absorb rather than reflect sunlight, which in turn causes more global warming. That type of feedback loop combined with the inertia of the climate system means climate change doesn’t move along smooth, linear plots on a line graph.

Armour found that while observations might show climate sensitivity to be on the lower end, the models are picking up quite well the amount of warming that emerges over the long-term.

“The conclusions are really two-fold,” said Armour. “When the models are treated consistently with the observations, that is measuring climate sensitivity within the models in the same way you would with the observations, it brings that value of sensitivity in the models downward, meaning they’re not too sensitive.”

“But the other way you could view the results,” he added, “is that the model range of future warming is rather realistic, meaning that our apparent climate sensitivity we get from the observations can be expected to increase in the future, meaning more global warming than you might naïvely expect from taking just that low value that people have been talking about from the observations.”

Gavin Schmidt, a NASA climate scientist not involved in the study, said Armour's findings complemented the results of a 2016 report on climate sensitivity conducted by researchers at NASA and Columbia University.

“What Armour finds is that [feedback loops] do change and in such a way that if you estimate the final sensitivity from just the early period you will end up underestimating the ECS,” he said in an email. “This is important because that’s almost exactly what’s happening when we try and use recent temperature trends to estimate the ECS. Those estimates have tended to come in lower than others, in ways that aren’t consistent with our understandings of processes or paleoclimate. So this result makes those studies much more consistent with other methods.”

Armour pointed to a pair of feedbacks that have yet to take effect, but are likely to lead to significant levels of warming.

“Over the next several decades to centuries we expect the Southern Ocean to warm up almost as much as the Arctic and get that big, positive feedback to start kicking in,” he said. “So it’s really that delay in the positive feedbacks kicking in that causes this increase in climate sensitivity into the future.”

That feedback in the southern hemisphere is projected to occur when ocean temperatures in the Southern Ocean warm, melting sea ice, like is already happening in the Arctic, causing the ocean to absorb more sunlight and leading to greater amounts warming.

Increased warming in the eastern tropical Pacific over the next several decades, he added, is is likely to diminish cloud cover in the region. That cloud cover, like sea ice in the Arctic and Southern Ocean, reflects incoming sunlight.

“Initially in the very early stages of global warming, like today, like we’ve seen over the last hundred years, your clouds in the eastern tropical Pacific are actually acting to limit global warming, it has a negative, damping impact,” he said. “But in the future, say over the next several decades, we expect those to be a positive feedback, enhancing global warming.”

Read more at Discovery News

Mythic Giant Shipworm Survives on Fart Gas and Bacteria

A rare species of giant shipworm has mostly lived in myth since its 3 to 5 foot-long tusk-resembling shells were first documented in the 18th century. Shipworms  — which are actually a type of saltwater clam — once conquered the seas by feasting on wood, sinking ships in the process, but this particular species, Kuphus polythalamia, was recently found planted like carrots in mud at the bottom of a lagoon in Mindanao, Philippines.

The stench of the site, which was previously used as a log storage area, was overwhelming, yet researchers from Sultan Kudarat State University managed to collect five live Kuphus individuals, allowing them to study the live specimen inside the shell for the first time.

The scientists packed their precocious cargo into PVC pipes and escorted the shipworms to the University of the Philippines, where Daniel Distel and his team eagerly awaited their arrival.

“We really did not know what to expect,” Distel, a research professor and director of the Ocean Genome Legacy Center at Northeastern University, told Seeker. “Most clams are white or beige or pinkish inside.”

His colleague Margo Haygood described the moment when they first set eyes on the live giant shipworms.

“We turned the pipes upright and filled them with seawater and airstones and put the animals in to acclimate," she recalled. "Before long, I looked into the pipe and could see a strong jet of water coming out of the animal’s siphon. It was alive!”

“The animal inside is dark gray, shiny and floppy,” added Haygood, who is a research professor in medicinal chemistry at the University of Utah College of Pharmacy. “It looks like an alien creature.”

The researchers continued to investigate the specimens, with their results reported in the journal Proceedings of the National Academy of Sciences.

The scientists determined that, unlike other shipworms, which munch on wood in the ocean, Kuphus depends on two primary things for its survival: hydrogen sulfide and beneficial bacteria that live in its gills. Hydrogen sulfide, commonly found in rotten eggs and human flatulence, is very poisonous, corrosive, and flammable in large amounts.

Kuphus loves it, though. Distel explained that the bacteria burn it “the same way we burn carbohydrate or sugar to make energy.” The bacteria-made sugars are ultimately what the shipworm lives on. It would seem to have an endless supply of hydrogen sulfide, since its organic-rich mud habitat emits the smelly gas in large quantities.

A scientist removes the top of a shipworm shell to reveal the living animal inside.

It is a mystery as to how Kuphus evolved this unusual mode of survival. What is known is that its wood-eating relatives have had a tougher time finding food since human activity has actually reduced the overall amount of wood in the oceans.

Distel explained, “Most wood gets in the oceans via erosion of coastal forests and riverbanks. People like to clear forests away from coasts and riverbanks so they can build homes, businesses and resorts. We also like to build dams and have dammed most of the great rivers of the world. As a result, a lot less wood makes it to the sea.”

Read more at Discovery News

Tatooine-Like Planets May Be ‘Excellent Candidates’ for Supporting Life

This artist's concept shows a hypothetical planet covered in water around the binary star system of Kepler-35A and B.

Life on an alien planet with two suns in its sky, like Luke Skywalker's home world Tatooine in the "Star Wars" films, may indeed be possible, a new study suggests.

A Tatooine world could be habitable despite its inevitably complicated orbit, as long as the planet stays within a particular range of distances from its two host stars, researchers said.

"This means that double-star systems of the type studied here are excellent candidates to host habitable planets, despite the large variations in the amount of starlight hypothetical planets in such a system would receive," Max Popp, an associate research scholar at Princeton University in New Jersey and the Max Planck Institute of Meteorology in Hamburg, Germany, said in a statement.

Popp and Siegfried Eggl, a Caltech postdoctoral scholar at NASA's Jet Propulsion Laboratory in Pasadena, California, investigated the "habitable zone" for Tatooine worlds — that just-right range of orbital distances at which liquid water, and perhaps life as we know it, could exist on a planet's surface.

Nailing down the habitable zone for single-star planets isn't simple or straightforward; details of the zone depend heavily on the nature of a world's atmosphere, for example. But habitable zones get even trickier when the planet in question has two suns.

Tatooine planets' habitable zones, after all, depend on the distance from the two host stars' center of mass, not just the distance from any particular star. And Tatooine worlds don't orbit in a circular path; their paths wobble considerably due to the gravitational influences of their parent stars, researchers said.

To better understand such factors, Popp and Eggl modeled conditions on a hypothetical Earth-size, water-covered world in Kepler-35, a real two-star system more than 5,000 light-years from Earth that's known to host a planet eight times more massive than our own. (Popp and Eggl ignored the gravitational influence of this actual planet, which is known as Kepler-35b, for simplicity's sake.)

"Our research is motivated by the fact that searching for potentially habitable planets requires a lot of effort, so it is good to know in advance where to look," Eggl said in the same statement. "We show that it's worth targeting double-star systems."

The duo's simulations investigated what this imaginary Tatooine world's climate would be like if it orbited with periods between 341 and 380 Earth days.

They found that, near the outer edge of Kepler-35's presumed habitable zone, the planet would be relatively cold and dry. The dearth of atmospheric water vapor would also make the climate quite variable; global average surface temperatures would swing by as much as 3.6 degrees Fahrenheit (2 degrees Celsius), the researchers said.

"This is analogous to how, on Earth, in arid climates like deserts, we experience huge temperature variations from day to night," Eggl said. "The amount of water in the air makes a big difference."

Read more at Discovery News

New insights into 'ocean worlds' in our solar system

This graphic illustrates how Cassini scientists think water interacts with rock at the bottom of the ocean of Saturn's icy moon Enceladus, producing hydrogen gas.

Two veteran NASA missions are providing new details about icy, ocean-bearing moons of Jupiter and Saturn, further heightening the scientific interest of these and other "ocean worlds" in our solar system and beyond. The findings are presented in papers published Thursday by researchers with NASA's Cassini mission to Saturn and Hubble Space Telescope.

In the papers, Cassini scientists announce that a form of chemical energy that life can feed on appears to exist on Saturn's moon Enceladus, and Hubble researchers report additional evidence of plumes erupting from Jupiter's moon Europa.

"This is the closest we've come, so far, to identifying a place with some of the ingredients needed for a habitable environment," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at Headquarters in Washington. "These results demonstrate the interconnected nature of NASA's science missions that are getting us closer to answering whether we are indeed alone or not."

The paper from researchers with the Cassini mission, published in the journal Science, indicates hydrogen gas, which could potentially provide a chemical energy source for life, is pouring into the subsurface ocean of Enceladus from hydrothermal activity on the seafloor.

The presence of ample hydrogen in the moon's ocean means that microbes -- if any exist there -- could use it to obtain energy by combining the hydrogen with carbon dioxide dissolved in the water. This chemical reaction, known as "methanogenesis" because it produces methane as a byproduct, is at the root of the tree of life on Earth, and could even have been critical to the origin of life on our planet.

Life as we know it requires three primary ingredients: liquid water; a source of energy for metabolism; and the right chemical ingredients, primarily carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. With this finding, Cassini has shown that Enceladus -- a small, icy moon a billion miles farther from the sun than Earth -- has nearly all of these ingredients for habitability. Cassini has not yet shown phosphorus and sulfur are present in the ocean, but scientists suspect them to be, since the rocky core of Enceladus is thought to be chemically similar to meteorites that contain the two elements.

"Confirmation that the chemical energy for life exists within the ocean of a small moon of Saturn is an important milestone in our search for habitable worlds beyond Earth," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.

The Cassini spacecraft detected the hydrogen in the plume of gas and icy material spraying from Enceladus during its last, and deepest, dive through the plume on Oct. 28, 2015. Cassini also sampled the plume's composition during flybys earlier in the mission. From these observations scientists have determined that nearly 98 percent of the gas in the plume is water, about 1 percent is hydrogen and the rest is a mixture of other molecules including carbon dioxide, methane and ammonia.

The measurement was made using Cassini's Ion and Neutral Mass Spectrometer (INMS) instrument, which sniffs gases to determine their composition. INMS was designed to sample the upper atmosphere of Saturn's moon Titan. After Cassini's surprising discovery of a towering plume of icy spray in 2005, emanating from hot cracks near the south pole, scientists turned its detectors toward the small moon.

Cassini wasn't designed to detect signs of life in the Enceladus plume -- indeed, scientists didn't know the plume existed until after the spacecraft arrived at Saturn.

"Although we can't detect life, we've found that there's a food source there for it. It would be like a candy store for microbes," said Hunter Waite, lead author of the Cassini study.

The new findings are an independent line of evidence that hydrothermal activity is taking place in the Enceladus ocean. Previous results, published in March 2015, suggested hot water is interacting with rock beneath the sea; the new findings support that conclusion and add that the rock appears to be reacting chemically to produce the hydrogen.

The paper detailing new Hubble Space Telescope findings, published in The Astrophysical Journal Letters, reports on observations of Europa from 2016 in which a probable plume of material was seen erupting from the moon's surface at the same location where Hubble saw evidence of a plume in 2014. These images bolster evidence that the Europa plumes could be a real phenomenon, flaring up intermittently in the same region on the moon's surface.

The newly imaged plume rises about 62 miles (100 kilometers) above Europa's surface, while the one observed in 2014 was estimated to be about 30 miles (50 kilometers) high. Both correspond to the location of an unusually warm region that contains features that appear to be cracks in the moon's icy crust, seen in the late 1990s by NASA's Galileo spacecraft. Researchers speculate that, like Enceladus, this could be evidence of water erupting from the moon's interior.

"The plumes on Enceladus are associated with hotter regions, so after Hubble imaged this new plume-like feature on Europa, we looked at that location on the Galileo thermal map. We discovered that Europa's plume candidate is sitting right on the thermal anomaly," said William Sparks of the Space Telescope Science Institute in Baltimore. Sparks led the Hubble plume studies in both 2014 and 2016.

The researchers say if the plumes and the warm spot are linked, it could mean water being vented from beneath the moon's icy crust is warming the surrounding surface. Another idea is that water ejected by the plume falls onto the surface as a fine mist, changing the structure of the surface grains and allowing them to retain heat longer than the surrounding landscape.

For both the 2014 and 2016 observations, the team used Hubble's Space Telescope Imaging Spectrograph (STIS) to spot the plumes in ultraviolet light. As Europa passes in front of Jupiter, any atmospheric features around the edge of the moon block some of Jupiter's light, allowing STIS to see the features in silhouette. Sparks and his team are continuing to use Hubble to monitor Europa for additional examples of plume candidates and hope to determine the frequency with which they appear.

NASA's future exploration of ocean worlds is enabled by Hubble's monitoring of Europa's putative plume activity and Cassini's long-term investigation of the Enceladus plume. In particular, both investigations are laying the groundwork for NASA's Europa Clipper mission, which is planned for launch in the 2020s.

"If there are plumes on Europa, as we now strongly suspect, with the Europa Clipper we will be ready for them," said Jim Green, Director of Planetary Science, at NASA Headquarters.

Read more at Science Daily

Meet 'DeeDee,' a distant, dim member of our solar system

Artist concept of the planetary body 2014 UZ224, more informally known as DeeDee. ALMA was able to observe the faint millimeter-wavelength "glow" emitted by the object, confirming it is roughly 635 kilometers across. At this size, DeeDee should have enough mass to be spherical, the criteria necessary for astronomers to consider it a dwarf planet, though it has yet to receive that official designation.

Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have revealed extraordinary details about a recently discovered far-flung member of our solar system, the planetary body 2014 UZ224, more informally known as DeeDee.

At about three times the current distance of Pluto from the Sun, DeeDee is the second most distant known trans-Neptunian object (TNO) with a confirmed orbit, surpassed only by the dwarf planet Eris. Astronomers estimate that there are tens-of-thousands of these icy bodies in the outer solar system beyond the orbit of Neptune.

The new ALMA data reveal, for the first time, that DeeDee is roughly 635 kilometers across, or about two-thirds the diameter of the dwarf planet Ceres, the largest member of our asteroid belt. At this size, DeeDee should have enough mass to be spherical, the criteria necessary for astronomers to consider it a dwarf planet, though it has yet to receive that official designation.

"Far beyond Pluto is a region surprisingly rich with planetary bodies. Some are quite small but others have sizes to rival Pluto, and could possibly be much larger," said David Gerdes, a scientist with the University of Michigan and lead author on a paper appearing in the Astrophysical Journal Letters. "Because these objects are so distant and dim, it's incredibly difficult to even detect them, let alone study them in any detail. ALMA, however, has unique capabilities that enabled us to learn exciting details about these distant worlds."

Currently, DeeDee is about 92 astronomical units (AU) from the Sun. An astronomical unit is the average distance from Earth to the Sun, or about 150 million kilometers. At this tremendous distance, it takes DeeDee more than 1,100 years to complete one orbit. Light from DeeDee takes nearly 13 hours to reach Earth.

Gerdes and his team announced the discovery of DeeDee in the fall of 2016. They found it using the 4-meter Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile as part of ongoing observations for the Dark Energy Survey, an optical survey of about 12 percent of the sky that seeks to understand the as-yet mysterious force that is accelerating the expansion of the universe.

The Dark Energy Survey produces vast troves of astronomical images, which give astronomers the opportunity to also search for distant solar system objects. The initial search, which includes nearly 15,000 images, identified more than 1.1 billion candidate objects. The vast majority of these turned out to be background stars and even more distant galaxies. A small fraction, however, were observed to move slowly across the sky over successive observations, the telltale sign of a TNO.

One such object was identified on 12 separate images. The astronomers informally dubbed it DeeDee, which is short for Distant Dwarf.

The optical data from the Blanco telescope enabled the astronomers to measure DeeDee's distance and orbital properties, but they were unable to determine its size or other physical characteristics. It was possible that DeeDee was a relatively small member of our solar system, yet reflective enough to be detected from Earth. Or, it could be uncommonly large and dark, reflecting only a tiny portion of the feeble sunlight that reaches it; both scenarios would produce identical optical data.

Since ALMA observes the cold, dark universe, it is able to detect the heat -- in the form of millimeter-wavelength light -- emitted naturally by cold objects in space. The heat signature from a distant solar system object would be directly proportional to its size.

"We calculated that this object would be incredibly cold, only about 30 degrees Kelvin, just a little above absolute zero," said Gerdes.

While the reflected visible light from DeeDee is only about as bright as a candle seen halfway the distance to the moon, ALMA was able to quickly home in on the planetary body's heat signature and measure its brightness in millimeter-wavelength light.

This allowed astronomers to determine that it reflects only about 13 percent of the sunlight that hits it. That is about the same reflectivity of the dry dirt found on a baseball infield.

By comparing these ALMA observations to the earlier optical data, the astronomers had the information necessary to calculate the object's size. "ALMA picked it up fairly easily," said Gerdes. "We were then able to resolve the ambiguity we had with the optical data alone."

Objects like DeeDee are cosmic leftovers from the formation of the solar system. Their orbits and physical properties reveal important details about the formation of planets, including Earth.

This discovery is also exciting because it shows that it is possible to detect very distant, slowly moving objects in our own solar system. The researchers note that these same techniques could be used to detect the hypothesized "Planet Nine" that may reside far beyond DeeDee and Eris.

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Collisions generate gas in debris disks

This is an artist's impression of gas generation from the collision between objects in a debris disk.

Many young stars, as well as more middle-aged stars like our sun, have "debris disks" -- like the Oort Cloud in our own solar system -- that are believed to be remnants of the system's formation. Recently, radio observations have detected gas within a number of such discs, but it was not clear why the gas was there. There are two major hypotheses: either the gas is primordial gas from the original gas cloud that formed the star, or it originates from collisions between objects in the disk.

In search of a solution to this problem, a team from the RIKEN Star and Planet Formation Laboratory decided to look at emissions of carbon, which are important as they can provide clues to the origin of the gas. Normally, carbon will exist mostly in a molecular form, as carbon monoxide. Ultraviolet light from the central star will "dissociate" the atoms, creating free atomic carbon, but normally a chemical reaction -- mediated by hydrogen -- recombines the carbon into CO. However, if there is no hydrogen, then the reaction does not take place and the carbon remains in its atomic state.

Aya Higuchi, the first author of the paper, published in Astrophysical Journal Letters, was able to use the ten-meter Atacama Submillimeter Telescope Experiment (ASTE) in Chile to examine the atomic carbon line from two young star systems -- 49 Ceti and Beta Pictoris -- that are known to have debris disks. They then compared this from data on CO taken by the Atacama Large Millimeter/submillimeter Array (ALMA), an array of telescopes in the same facility. "We were surprised," she says, "to find atomic carbon in the disk, the first time this observation has been made at sub-millimeter wavelength. But more so, we were surprised at how much there was. It was about as common as the carbon monoxide."

The implication, at least for these two star systems, is that there is very little hydrogen to drive the carbon back into CO. Because hydrogen makes up most of the gas in protoplanetary clouds, this hints that the gas is not primordial, but rather is generated from some process taking place in the debris disk. Gas has been found in other debris disks, but is not found in all. Higuchi says, "If we can perform similar measurements on other young stars, it will help to clarify the origin of the gas in debris disk. Our data here suggests that the gas is secondary."

Looking to the future, she continues, "This work will also help to understand how a protoplanetary disk evolves into a debris disks by distinguishing the origin of the gas in the disks."

The work was done in collaboration with scientists from Ibaraki University and Nagoya University.

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Moabosaurus discovered in Utah's 'gold mine'

BYU researcher Brooks Britt is with the newly discovered Moabosaurus, on display at BYU's Museum of Paleontology.

Move over, honeybee and seagull: it's time to meet Moabosaurus utahensis, Utah's newly discovered dinosaur, whose past reveals even more about the state's long-term history.

The Moabosaurus discovery was published this week by the University of Michigan's Contributions from the Museum of Paleontology. The paper, authored by three Brigham Young University researchers and a BYU graduate at Auburn University, profiles Moabosaurus, a 125-million-year-old dinosaur whose skeleton was assembled using bones extracted from the Dalton Wells Quarry, near Arches National Park.

BYU geology professor and lead author Brooks Britt explained that in analyzing dinosaur bones, he and colleagues rely on constant comparisons with other related specimens. If there are enough distinguishing features to make it unique, it's new.

"It's like looking at a piece of a car," Britt said. "You can look at it and say it belongs to a Ford sedan, but it's not exactly a Focus or a Fusion or a Fiesta. We do the same with dinosaurs."

Moabosaurus belongs to a group of herbivorous dinosaurs known as sauropods, which includes giants such as Brontosaurus and Brachiosaurus, who had long necks and pillar-like legs. Moabosaurus is most closely related to species found in Spain and Tanzania, which tells researchers that during its time, there were still intermittent physical connections between Europe, Africa and North America.

Moabosaurus lived in Utah before it resembled the desert we know -- when it was filled with large trees, plentiful streams, lakes and dinosaurs. "We always think of Moab in terms of tourism and outdoor activities, but a paleontologist thinks of Moab as a gold mine for dinosaur bones," Britt said.

In naming the species, Britt and his team, which included BYU Museum of Paleontology curator Rod Scheetz and biology professor Michael Whiting, decided to pay tribute to that gold mine. "We're honoring the city of Moab and the State of Utah because they were so supportive of our excavation efforts over the decades it's taken us to pull the animal out of the ground," Britt said, referencing the digs that began when he was a BYU geology student in the late '70s.

A previous study indicates that a large number of Moabosaurus and other dinosaurs died in a severe drought. Survivors trampled their fallen companions' bodies, crushing their bones. After the drought ended, streams eroded the land, and transported the bones a short distance, where they were again trampled. Meanwhile, insects in the soils fed on the bones, leaving behind tell-tale burrow marks.

"We're lucky to get anything out of this site," Britt said. "Most bones we find are fragmentary, so only a small percentage of them are usable. And that's why it took so long to get this animal put together: we had to collect huge numbers of bones in order to get enough that were complete."

BYU has a legacy of collecting dinosaurs that started in the early 1960s, and Britt and colleagues are continuing their excavation efforts in eastern Utah. Moabosaurus now joins a range of other findings currently on display at BYU's Museum of Paleontology -- though, until its placard is updated, it's identified as "Not yet named" (pronunciation: NOT-yet-NAIM-ed).

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