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The image captures the formation of a planet around PDS 70, a dwarf star located 370 light-years from Earth.

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Credit: ESO/A. Müller et al

An international team of astronomers has released the first image ever captured of a planet being born in deep space.

The image, captured with advanced, surface-based telescopes, shows the new planet developing around the dwarf star PDS 70, which is located around 370 light-years from Earth.

The new planet — named PDS 70b — is orbiting roughly three billion miles from the central star, around the same distance between Uranus and the sun. Further analysis shows that the new planet is a giant gas planet with a total mass several times that of Jupiter. The planet is much hotter than anything in our solar system, too, with a surface temperature of around 1,000 degrees Celsius.

The image was produced by an advanced piece of equipment within the Very Large Telescope array at the European Southern Observatory's facility in northern Chile. The SPHERE device — which stands for Spectro-Polarimetric High-contrast Exoplanet REsearch instrument — studies exoplanets and discs around nearby stars using a technique known as high-contrast imaging.

The astronomy team that captured the new image was led a group from the Max Planck Institute for Astronomy in Heidelberg, Germany. 

To even be able to see the new planet, the telescope had to first block out the bright light of the central star itself. To that end, the SPHERE system incorporates a coronagraph, which obscures the blinding light of the central star and allows astronomers to detect the much fainter light bouncing off the planet and the spinning disk of coronal materials.

“These disks around young stars are the birthplaces of planets, but so far only a handful of observations have detected hints of baby planets in them,” lead researcher Miriam Keppler said in a statement released with the new image. “The problem is that until now, most of these planet candidates could just have been features in the disk.”

RELATED: Mysterious Interstellar Object ‘Oumuamua Has Finally Been Identified

The discovery of PDS 70b is a significant event for astronomers, and subsequent teams of researchers are already following up on the initial research. In fact, it was a secondary team that captured the remarkable image.

The image isn't just pretty, either. By carefully parsing the data underlying the new imagery, astronomers are able to determine some of the planet's chemical and physical properties. This, in turn, enables scientists to test theoretical models of planet formation.

“Keppler's results give us a new window onto the comple and poorly-understood early stages of planetary evolution,” said André Müller, a postdoctoral researcher at the Max Planck Institute for Astronomy and leader of the second team to investigate the new planet. “We needed to observe a planet in a young star's disc to really understand the processes behind planet formation.”

Two studies describing the findings were published in the journal Astronomy and Astrophysics.


Seeker's Bad Science podcast explores the surprisingly complex scientific principles in Pixar's 2008 computer-animated sci-fi classic.

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In 2008, Pixar Animation Studios released the sci-fi parable WALL-E, considered by many genre connoisseurs to be among the very best computer-animated films ever made. Besides being funny and visually dazzling, WALL-E does what good science fiction is supposed to do — it takes present-day issues and extrapolates them out to the event horizon.

In the case of WALL-E, the central issue is America's unsustainable obsession with material consumption and what that means for the future of our planet and our species. In the future, humans have abandoned Earth due to radical pollution problems. The planet's surface is piled high with trash, the atmosphere is choked with smog, and a cloud of orbiting space garbage blots out the stars. In search of a new home planet, a delegation from humanity sets out in a generation starship on a trip that lasts 700 years.

In this week's installment of Bad Science, Seeker's podcast on science versus fiction at the movies, host Ethan Edenburg is joined by James Hicks, one of the original science advisers on WALL-E and a professor of ecology and evolutionary biology at the University of California, Irvine. Also on hand to think out loud and crack wise is comedian Ian Abramson.

As Hicks explains in this week's episode, part of his work on the film was to speculate on what human beings might look like after spending 700 years in space. Fans of the film will recall that the story's human characters are terminally obese and very nearly immobile.

“[The script] evolved to the idea that they would be fat, based on some of the physiological changes that take place when you're in a microgravity environment,” Hicks says “When you're in space, you lose muscle mass and you lose bone density.”

In fact, Hicks did the math to estimate the physiological changes that would happen to long-term pilgrims in space. Previous data suggests humans lose muscle mass and bone density at a rate of about two percent per month, so Hicks multiplied that out over several years and generations to arrive at the body shape of the film's future colonists.

Hicks also delves into the real-world programs developed by NASA and other space agencies to counteract the effects of microgravity environments. A big part of that, it turns out, is simply doubling down on terrestrial physical therapy regimens that have already proven effective here on Earth — cardiovascular exercise and resistance training.

“You can't change your chronological age, but you can change your physiological age,” Hicks says.

RELATED: Set Phasers to Stun: The Science Behind Star Trek

Also in this week's episode, host Edenburg leads the panel through a series of sound clips from the film, exploring various audio elements with WALL-E designer Ben Burt — the legendary sound man behind blockbuster franchises including Star Wars and Indiana Jones. If you've ever wanted to know how Hollywood typically makes the sound of laser guns … well, you'll want to tune into this week's game: It Doesn't Burt to Know About Sound Design.

Click on over for more facts and figures on the surprisingly sophisticated science behind WALL-E, including some intriguing details on mitochondria, epigenetics, and phenotypic plasticity.

A pulsar orbited by a white dwarf star, which are both orbited by another white dwarf, provide confirmation of the principle of universality of free fall.

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Credit: ASTRON

A crucial part of Albert Einstein's theory of relativity is based on a principle called the universality of free fall, which means that all falling objects accelerate identically, regardless of their mass or composition. But does the presence of extreme gravity change how objects move?

Some alternative theories of gravity have suggested this might be so. Until now, however, scientists have never been able to fully test this question. Thanks to a unique triple star system, this key prediction of Einstein’s theory has passed one of the most rigorous tests ever, showing that all objects do accelerate the same, no matter how strong the external gravitational field.   

An international team of astronomers conducted the test by combining 818 observations over six years from three different observatories, making approximately 27,000 measurements of a star system named PSR J0337+1715, located about 4,200 light-years from Earth. Their findings were published today in the journal Nature.  

This triple star system contains three end-of-life stars: A pulsar orbited closely by a white dwarf star, which are, in turn, both orbited by another white dwarf that is about 1 AU away, which is the same distance between Earth and the sun. This system allows for an investigation of how the pull of the outer white dwarf influences both the inner dwarf and the companion pulsar, which has strong self-gravity.

Lead author Anne Archibald, a postdoctoral researcher of the University of Amsterdam and ASTRON, the Netherlands Institute for Radio Astronomy, told Seeker that this is the only pulsar known to be in a system with two other stars. Triple systems are very delicate, she said, and very few survive the supernova explosion that creates the pulsar. And it was the discovery of this unique system that spurred this test of Einstein’s theory.  

“To do this test, we needed a pulsar, with its regular radio pulses and its incredible density," as well as other objects in the system, Archibald explained. “The pulsar — a rapidly rotating neutron star — rotates 366 times per second, and beams of radio waves produce pulses at regular intervals, and we can use these pulses to track the pulsar.”

If the pulsar and the inner white dwarf fall differently towards the outer white dwarf, then the pulses would arrive at a different time than expected.

Archibald and her colleagues used three kinds of observations to make very sensitive measurements to determine if the pulsar moved the same way as the inner white dwarf. They made frequent observations taken with the Westerbork Synthesis Radio Telescope in the Netherlands, less frequent but long (10-hour) observations with the Robert C. Byrd Telescope at Green Bank, West Virginia, and short monthly observations with the very sensitive William E. Gordon Telescope at Arecibo, Puerto Rico.

“Having all three of these telescopes allowed us to check them against each other,” Archibald said via email. “These cross-checks were essential to confirming that our test was giving correct results.”

Their measurements were so sensitive that the team was hoping to be able to detect a deviation from Einstein's prediction as small as two meters. But they ran into challenges due to a number of complicated effects.

“For example, every March our line of sight to the pulsar passes within 2.1 degrees of the sun,” Archibald said. “The solar wind at that point introduces delays in the radio signals we observe. Unfortunately, the solar wind flows out in different directions and different amounts on different days, so compensating for these delays was difficult.”

Credit: Cees Bassa

They compensated, but realized they could only could only reliably detect a deviation from Einstein's predictions as big as 30 meters.

“Fortunately, 30 meters was still a very stringent test of Einstein's theory,” Archibald said.

While the pulsar was measured with radio observations, the team measured the motion of the inner companion’s orbit based on optical observations, measuring the Doppler shifts of the white dwarf’s spectrum, the same way some exoplanets are found.

The effect of any deviation from Einstein’s gravity would be very distinctive, the team said, and they could see that signature from only the measurements of the pulsar’s motion.

They did not detect any difference between the accelerations of the neutron star and inner white dwarf, and if there is a difference, it would be no more than three parts in a million, Archibald said.   
 
RELATED: Astronomers Capture the First Image of a Planet Being Born
 
The team wrote in their paper that previous tests of this principle using objects in our own solar system have been limited by the weak self-gravity of these bodies, and tests using pulsar–white-dwarf binary systems have been limited by the weak gravitational pull of the Milky Way. This new test has improved on the accuracy on any previous test of gravity by a factor of about ten.

One of the most famous tests of universal free fall came in 1971 when astronaut Dave Scott dropped a hammer and a feather on the Moon during Apollo 15. This was a re-creation of a supposed test by Galileo where he dropped two balls made of differing materials off the Leaning Tower of Pisa, and observed them reaching the ground at the same time.

Were the observations made by Archibald and her team comparable to these famous earlier tests?

“Indeed!” Archibald said. “Galileo argued that it didn't matter how massive a cannonball was, or what it was made of, it would always fall exactly the same way. Of course, on Earth air gets in the way, but Dave Scott demonstrated on the airless moon that it worked even with a feather. We actually asked the same question: Does our pulsar fall the same way as our white dwarf?”

Of course, Archibald and her colleagues couldn't drop the stars off a tower, but as the two inner objects move around their orbit with the outer companion, they are continually falling toward it. If the pulsar experienced a different acceleration from the white dwarf, its orbit would be shifted in a way they could detect. But they were testing the same thing: if the two objects fell the same way.

Archibald added that there is one important distinction about the reason the pulsar and white dwarf might fall differently. While it has been shown numerous times that mass and composition don’t affect how an object falls, her team was testing something different.

“In Einstein's theory, gravity itself has mass, so an object with really strong gravity could behave differently,” Archibald said. “In fact, once you have an object with strong gravity, Einstein's theory is almost the only one where objects with strong gravity fall the same way as normal objects. So, this is why we needed to use a pulsar: it’s incredibly strong gravity is what might make it fail Galileo's test.”

RELATED: Mysterious Interstellar Object ‘Oumuamua Has Finally Been Identified

Instead, this unique star system confirmed both Galileo’s theory of motion and Einstein’s theory of gravity.

As for any future tests, Archibald and her team said the upcoming Square Kilometer Array, located in South Africa, might be able to find other star systems such as unusual binaries, other triple star systems, or a pulsar orbiting a black hole that might test Einstein’s theory with tighter constraints.

But Archibald said all three of the telescopes used in this current test of fundamental physics performed admirably.

“Astronomy is a wonderful way to find out what's out there in the universe,” she said, “but this sort of observation is the only way to improve our understanding of a force as fundamental as gravity.”

Seeker's Bad Science podcast explores the marine biology behind Pixar's beloved fish tale.

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Pixar's 2003 classic Finding Nemo is a notorious tearjerker. The computer-animated film, which tells the tale of a lost little clownfish and his father's quest to find him, has earned its place in the pantheon of great family films. In fact, Finding Nemo still holds the record as the best-selling DVD of all time.

In this week's installment of Bad Science, Seeker's weekly podcast on the scientific principles behind popular movies, host Ethan Edenburg confirms Finding Nemo's reputation as an irresistible weepie. Also admitting to tears in this week's episode are special guests Misty Paig-Tran, a marine biologist at California State University, Fullerton, and actress Jackie Tohn of the Netflix series GLOW.

Paig-Tran brings her marine biology expertise to the show as the panel breaks down various elements of the movie and its depiction of underwater sea life. Paig-Tran's scholarly specialties include functional morphology, biomechanics, fluid mechanics, and materials testing.

Nemo fans will remember the crew of vegetarian sharks who swear off their usual diet in an effort to promote peace throughout the ocean. But can sharks really be vegetarian?

Kinda-sorta, Paig-Tran says.

“There are some sharks that, while not vegetarian, can process plant matter,” she explains. “That was a pretty big thing, in the shark field, when that was discovered.”

As for clownfish, the species that brings us li'l Nemo and his dad, it turns out that there is actually more than one species to consider. The latest numbers from marine biology researchers suggests there are currently about 28 to 30 species of clownfish.

“With marine biology, it's always changing,” Paig-Tran explains. “We don't ever really know how many of everything there is. Like there's a new species of manta that just came out two years ago.”

Speaking of which, the panel fishes out some related trivia on that species, too. It turns out that Mr. Ray, Nemo's science teacher in the movie, isn't a manta ray at all. He's a spotted eagle ray.

RELATED: Evolutionary Decline and Orbital Decay: The Science Behind WALL-E

Paig-Tran also tackles that abiding question from movies, tall tales, and ocean fables: Could a person really be swallowed by a whale and survive in the whale's stomach? “In the stomach, not so much,” she says. “Digestive juices.”

On the plus side, it's actually pretty much impossible for a person to be swallowed at all.

“Whales have an esophagus, and it closes, so it's not swallowing things it doesn't want,” Paig-Tran says. “It's also pretty small. Like, I would not fit in a whale's esophagus. And it would know I was there and would spit me out.”

So that's reassuring. Tune in for this week's episode for more details on fringe ichthyology, coral aquariums, and the inspirational legacy of the movie.

“We're fifteen years out from Finding Nemo,” Paig-Tran says. “How many kids are in high school right now saying, ‘I'm definitely going to be a marine biologist.’”

Elevated CO2 levels in the atmosphere could be reducing the medicinal properties of the milkweed plants that monarchs eat.

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Credit: Austin Thomason/Michigan Photography

A troubling ecology study published this week contains some bad news for monarch butterflies … and maybe humans, too.

According to new research conducted at the University of Michigan, elevated levels of atmospheric carbon dioxide are reducing the medicinal properties of milkweed plants. The compromised plants, in turn, are threatening the health of monarch butterflies, who rely on specific chemicals in milkweed to fend off disease and parasites.

The research details some very specific threats for monarch butterflies, who are already experiencing population decline due to habitat loss. But researchers warn that the study also suggests a much bigger potential problem for other species — including humans.

"If elevated carbon dioxide reduces the concentration of medicines in plants that monarchs use, it could be changing the concentration of drugs for all animals that self-medicate, including humans," said co-author Mark Hunter in press materials released with the new research.

Published Tuesday in the journal Ecology Letters, the research examines how elevated carbon dioxide levels alter the chemistry in milkweed plants, and how those changes in turn affect monarch butterflies. Milkweed leaves contain bitter toxins that help monarchs ward off predators and parasites.

Credit: Austin Thomason/Michigan Photography

In a multi-year experiment, researchers grew four different species of milkweed and subjected the plants to varying levels of atmospheric carbon dioxide. Using 40 different growth chambers, the research exposed milkweed plants to two different carbon dioxide levels. Twenty chambers were maintained at current global CO2 concentrations of around 400 parts per million. The other 20 chambers were ramped up to 760 ppm — a level that researchers say could be reached before the end of the century.

The study showed that some milkweed species essentially lost their medicinal properties when grown under the elevated CO2 levels. This triggered a steep decline in the monarch's ability to fight off a common parasite and reduced average lifespan by one week. That might not seem like a big deal, except that monarch butterflies only live two to six weeks.

RELATED: The Number of Monarch Butterflies in Western North America Is Plummeting

“We've been able to show that a medicinal milkweed species loses its protective abilities under elevated carbon dioxide,” said Leslie Decker, first author of the study. “Our results suggest that rising CO2 will reduce the tolerance of monarch butterflies to their common parasite and will increase parasite virulence.”

As to the broader implications of the study, Hunter notes that any animals, including humans, use chemicals in the environment to help them control parasites and diseases. What's more, nearly half of all human pharmaceuticals now in use were originally derived from natural sources.

“When we play Russian roulette with the concentration of atmospheric gases, we are playing Russian roulette with our ability to find new medicines in nature,” Hunter said.

The water conservation technology appears less sustainable than previously thought.

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Credit: Sandi Hemmerlein/AvoidingRegret.com

A new research paper published today in the journal Nature Sustainability throws some shade on a famous — well, relatively famous — water conservation technology.

In 2015, in the midst of a severe drought, California officials deposited more than 96 million shade balls into the Ivanhoe Reservoir in Los Angeles. About four inches in diameter, the small polyethylene balls were designed to provide a floating cover of shade and prevent sunlight from beating down on the reservoir's water supply.

The idea was to reduce water loss via evaporation and also to prevent certain chemical processes from triggering due to the intense direct sunlight. Images of the shade balls quickly went viral amid publicity surrounding California's extended drought.

But the newly published research confirms what many critics have long suspected: The shade ball approach wasn't quite the quick-and-easy solution that it first appeared to be.

According to the research team, the shade balls saved about 1.15 million cubic meters of water each year by preventing evaporation. However, the cost of manufacturing the balls costs around 0.25–2.9 million cubic meters of water, when you factor in the water resources required to manufacture the polyethylene in the first place.

In other words, the amount of water needed to produce the shade balls appears to be greater than the amount of water saved by preventing evaporation. The authors conclude that the shade ball method of water conservation only works if the balls are kept atop a reservoir for a sufficient amount of time. Depending on how you crunch the numbers, the shade balls don't actually start saving water until they've been afloat for several months or even years.

RELATED: Monarch Butterflies Are Threatened by Rising Carbon Dioxide Levels

Los Angeles has largely phased out the shade balls, replacing them with more traditional tarps and coverings. But the concept remains in circulation elsewhere as a water-management strategy. One recent proposal suggests the balls could be replaced with the equivalent of 12-sided dice.

This isn't the first time that the LA shade ball strategy has been criticized. Federal law requires that drinking water reservoirs be covered, and so the shade ball program was one of several considered by LA city planners prior to 2015. Critics contend that it was chosen primarily because it was cheaper than other solutions, like giant roofs or tarps.

But even the budget angle has been criticized. According to an oft-cited LA Weekly report, the shade balls cost $34.5 million to manufacture, but they save only $2 million per year. What's more, the shade balls need to be replaced every ten years. Do the math and that's $20 million of water savings for every $34.5 million of balls.

The new research suggests that, while shade balls made for good headlines and viral videos, the problem is going to require a bit more effort.

From the abstract: “The authors conclude that quick technological solutions to water management, such as shade balls, need integrated sustainability analyses to assess their overall viability.”

A leading researcher suggests the Red Planet’s harsh atmosphere means its surface might not be the most likely place to find the building blocks for life.

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Credit: NASA/JPL-Caltech/MSSS

If we're looking for life on Mars, start underground. That's the exhortation from a leading researcher who recently led a paper on organics compounds on Mars.

Organic compounds containing carbon, hydrogen, and other molecules such as nitrogen are common in the solar system. They're also sometimes an indication of life. But the compounds, just like life itself, are somewhat delicate. Radiation falling on the martian surface might destroy any organics that are there. Jennifer Eigenbrode suggests that by digging a little deeper researchers might find something interesting.

"Mars is full of surprises," Eigenbrode, an interdisciplinary astrobiologist at NASA's Goddard Space Flight Center in Maryland, told Seeker. "You could easily be fooled, but is there going to be organic matter there? Probably. Is it going to tell us what we want to know [about life]? Maybe. Something we didn't think to ask? Probably."

In June, Eigenbrode's team published a paper in the journal Science saying that NASA's Curiosity rover found organic molecules still preserved in 3-billion-year-old sedimentary rocks found at the base of Mount Sharp. It wasn’t Curiosity's first organics find, but it's the highest concentration of organics Curiosity had yet uncovered.

RELATED: NASA’s Curiosity Rover Detects Methane and Organic Material on Mars

The find is remarkable given that Curiosity's landing site, Gale Crater, was once a lake that probably had "all the ingredients necessary for life,"  such as chemical building blocks and energy sources, according to a NASA statement.

Because Eigenbrode's team found organic molecules in the top five centimeters (2 inches) of Martian soil, the researchers suggest that the find showed Mars might have been habitable. But the Mars of ancient days is not the same as Mars today.

The surface of Mars is likely not a friendly spot for life today, because it is baked in radiation and lacking abundant water. While little is known about the interior of Mars, Eigenbrode suggests that microorganisms beneath the surface would be sheltered from the radiation and be in closer proximity to sources of water from which they could draw energy.

Mars was likely more habitable in the distant past, because there is extensive evidence of water running on its surface, such as river features or rocks, which formed in watery environments. But as the atmosphere of Mars thinned over billions of years, there was not enough atmospheric pressure for water to keep flowing.

Why did the martian atmosphere disappear? Some researchers suggest it’s because the sun’s constant stream of charged particles knocked away carbon and other types of molecules in the atmosphere. Since Mars has no global magnetic field to deflect the sun’s particles, they were able to crash directly into these molecules and knock them out into space.

NASA’s MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft is currently investigating martian atmospheric loss.

RELATED: How Mars Went From Warm and Wet to Cold and Dry

Researchers said the newfound organics on Mars were especially tough. They were embedded within 3.5-billion-year-old rock, surviving wind, water, and changes on the surface of Mars, and were exposed only after being heated in an oven aboard Curiosity.

Curiosity isn't designed to probe the organics much further; its real mission is to search for habitable environments, not life itself. But future Mars missions will probe further. The European Space Agency's Mars 2020 rover is designed to drill down to a depth of at least two meters, collecting samples along the way.

Eigenbrode said she can't wait to see if Mars 2020 finds organics.

Other researchers argue life could be present on the surface of Mars. Mysterious features called recurring slope lineae tend to pop up on the slopes of craters, appearing as dark streaks during warmer weather. Some measurements suggest RSL include a sort of briny water, while other researchers argue the water may be from the atmosphere. But if there is running water there, microbes might also be inside.

RELATED: Mars 2020 Could Return to Where NASA's Spirit Rover Roamed

Mars is just one location in the solar system where we've detected organics. In late June, another research team using the Cassini spacecraft announced they found complex organics in a water plume jetting up from the icy moon of Enceladus.

In recent years, the Dawn spacecraft found tar-like organics on the surface of dwarf planet Ceres, and the Rosetta spacecraft detected organics such as the amino acid glycine on Comet 67P/Churyumov-Gersimenko. Organics were even found on Mercury, the planet that orbits closest to our sun.

Eigenbrode urged the space community to prioritize Mars in searching for organics. If we're going to send humans with all of our mini-microbial systems there, she warns, we need to know how our life and possible Martian life is going to mix. "If we don't give that sort of search due diligence,” she said, “it could come back to be troublesome for astronauts.”

Among the moons is Valetudo, which appears to have smashed into several of Jupiter’s large moons and broken them apart.

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Credit: Roberto Molar-Candanosa, courtesy of Carnegie Institution for Science.

A newly discovered moon around Jupiter — spotted traveling in a strange orbit — likely crashed into some of the gas giant's other satellites long ago, transforming a few worlds into many.

The moon, named Valetudo after the great-granddaughter of the Roman god Jupiter, is among 12 new moons found around the planet.

But the oddball moon may be the most interesting because it tells researchers more about what Jupiter's moons looked like long ago.

Researchers have known that Jupiter had three groups of moons. There were the Galilean moons, first discovered by Italian scientist Galileo in the 16th-century, which formed from a cloud of gas and dust around Jupiter while the giant planet was young.

Two other groups of moons are essentially objects captured by Jupiter's orbit when they flew too close to the huge planet. Prograde moons travel in the same direction as Jupiter's rotation, but are located beyond the closely orbiting Galileans. Retrograde moons travel opposite to Jupiter's spin and in the outer reaches of the Jovian system.

Eleven of the 12 new moons fit into these prograde or retrograde groups, but not the oddball Valetudo.

Valetudo is zipping along in an orbit that is opposite to its retrograde neighbors and that crosses their paths at an inclined angle. In other words, the moon is like a car speeding along a highway in the wrong direction, Scott Sheppard, an astronomer at the Carnegie Institution of Science, told Seeker.

And like a car careening dangerously on a busy roadway, Valetudo caused celestial crashes in the past that broke a few retrograde moons into several.

"What we think happened was there were three much larger retrograde moons, which were hundreds of kilometers in size. The parent moons were hit by something and they were broken apart," Sheppard said, adding that the something was likely Valetudo.

Sheppard was principal investigator with the research team that made the discovery.

Credit: Carnegie Institution for Science

The moon we see today is the remainder of a much bigger world that blew apart after the crashes. While Valetudo is smaller now, it remains a menace to its conformist neighbors. Sheppard said another collision will likely happen during the solar system's lifetime.

Researchers would like to get a close-up look at the moons. The trouble is: Jupiter lies four times further from Earth than the sun. So a telescope isn’t able to capture much more than the moons’ orbits. For greater detail, a spacecraft is needed.

Jupiter does have a NASA spacecraft orbiting it right now, called Juno. But Juno is too close to the huge planet and its field of view is too small to capture images of the planet, Sheppard said. Instead, scientists will have to wait for a future spacecraft, either flying past Jupiter or orbiting it. One possibility is NASA's Europa moon mission planned in the late 2020s or early 2030s.

In the meantime, "we have to speculate about what they [the new moons] are made of," Sheppard said. "We think these moons are an intermediate type of object, half-rock and half-ice. They also are fragments of the early solar system before the planets were formed, which makes studying them important to learning about the solar system's history.”

RELATED: Unique Triple Star System Tests Einstein’s Theory of Relativity

Sheppard's team found the moons while searching for Planet Nine, a distant, undiscovered planet thought to be altering the paths of objects in our solar system.

"Jupiter was well-placed in the sky to kill two birds with one stone," Sheppard said.

The researchers targeted objects moving with Jupiter in the foreground, which revealed the 12 new moons. At the same time, they watched for Planet Nine or smaller, distant dwarf planets in the background.

Researchers found the new moons thanks to a telescope upgrade. They used the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile, which just received a dark energy camera optimized to look for faint objects in the sky. Sheppard added that his team performed similar moon searches at Uranus and Neptune — but came up empty.

The new find boosts Jupiter's moon count to 79, easily making it the most populous place for moons in our solar system. The runner-up is Saturn, which has 62.

Carnegie Institution for Science

Decades of high-resolution imagery now provide NASA scientists with a clear-eyed view of the moon’s surface.

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Credit: NASA via Getty Images

When humans next set foot on the moon, they'll have a special spacecraft guiding their steps. The Lunar Reconnaissance Orbiter has a high-resolution camera that takes pictures of the moon. And the pictures it beams back are far better than what the Apollo 11 crew had to work with when they landed on the moon 49 years ago today

In the past few months, the Trump administration tasked NASA with going back to the moon before attempting to land humans on Mars. The first missions won't happen until at least the 2020s, but the agency is already getting started. It recently held meetings with commercial companies that are interested in landing rovers and spacecraft on the surface.

'No shortage of information'
Noah Petro, the project scientist for LRO, told Seeker that NASA and lunar scientists already have some lunar landing zones identified. LRO has nine years of data from its science mission at the moon, and many more years are expected, Petro said. "We have no shortage of information of what we anticipate to be at the surface of almost every location of the moon," he said.

LRO has passed some locations while the sun was at different altitudes in the sky, providing a better sense of how treacherous the surface might be for a landing. The craft even caught stereo images of a few locations, which provide 3D views of the surface.

Petro recently co-authored a study with Apollo 17 geologist and astronaut Harrison "Jack" Schmitt, who said he was in awe of LRO's capabilities. Back in the days of Apollo, usually one mission would image the surface in anticipation of future landings. For example, Apollo 8 and Apollo 10 imaged what ended up being the Apollo 11 landing site, Petro said.

Where to go first?
While the moon has a smaller surface area than Asia, our neighbor still has an astounding 38.7 million kilometers (24 million miles) to explore, according to NASA. So which locations does NASA see as a priority?

Petro said it's hard to say where future explorers will go first, because scientific priorities change, but he gave a few ideas on possible landing areas.

One thought would be landing in a place where volatiles are present. In other words, zones where water ice may be on the surface. It could be a perfect spot for mining water for machines and people, depending on how much ice is present. The caveat is these zones tend to be in permanent shadow, making it difficult to generate power and warmth.

If the goal of the mission is to perform astronomy, there are zones on the far side of the moon that would be permanently shielded from radio interference on Earth. Or if protecting humans from radiation is the main concern, it's possible that future missions may want to land near some possible caves on the surface. But Petro said the caves probably have rough terrain inside, making them difficult to explore on foot or using rovers.

RELATED: Space Radiation Is Becoming More Dangerous for Astronauts

Some of the Apollo missions, including Apollo 17, searched for signs of volcanic features on the surface. That's also a priority of LRO, Petro said. "We've identified a wide range of volcanic features," he said. "The great thing about those is
they show us more about the interior of the moon and its thermal history, and there is definitely no shortage of interesting volcanic features all across the moon — far side and near side."

Would NASA visit the six sites that humans visited between 1969 and 1972, during Apollos 11, 12, 14, 15, 16 and 17? Petro said the agency "has its eyes on new terrain" because it views these sites as zones of cultural importance that they would like to preserve.

Some commercial companies, however, may return to these sites to look at the machinery there. These firms are interested in how well the rovers and landers and other equipment held up after nearly five decades on the surface, Petro said.

You can read more about LRO's latest findings at NASA's website.

New radar observations show a potentially massive source of liquid water below the southern ice cap of Mars.

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Credit: ESA, INAF. Graphic rendering by Davide Coero Borga, Media INAF

New radar observations from a spacecraft orbiting Mars suggest water deposits lurking under the planet's south pole. But whether it's water, sediments infused with water, or something else altogether will require more observations, researchers caution.

Researchers uncovered a strange signal using a low-frequency radar on the Mars Express spacecraft, called MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding). Observations between May 2012 and December 2015 showed "anomalously bright subsurface reflections" within the Planum Australe region, they report in a new paper in the journal Science. The possible water signal is buried 1.5 kilometers (0.93 miles) below the surface, in an area about 20 km (12.5 miles) wide.

After analyzing the MARSIS radar signals, the study team said the bright feature has something called "high dielectric permittivity, matching that of water-bearing materials." Dielectric permittivity is a measurement of how much electrical polarization a material has when probed by an external electric field, such as the one used with ground-penetrating radar.

"We based our discovery on the fact that rocks or soil with or without water have different electric properties — that's what the main issue is of this technology," co-author Elena Pettinelli told Seeker. Pettinelli is a researcher at Roma Tre University in Rome who specializes in probing under the subsurface of Earth and other planets.

Credit: USGS Astrogeology Science Center, Arizona State University, INAF

Pettinelli said a dielectric permittivity measurement between 20 and 22 is typical of wet sediments on Earth. The widely varying measurements on Mars suggest a reading above 15. Researchers said while the temperature near the poles would freeze pure water, that zone could contain dissolved magnesium, sodium, and calcium salts that would make a brine and allow the water to remain liquid.

Mars Express has been orbiting the Red Planet since 2003. Pettinelli said an anomalous signature was first detected in Planum Australe as far back as 2008, but radar were inconsistent. Up until 2010 or 2011, Pettinelli said, scientists weren't sure if the signal was due to a problem with the radar or something under the ice. So engineers sent a software update to MARSIS to better optimize it for observations of those subsurface reflections around the south pole. New radar collections starting in 2012 showed a much stronger signal, Pettinelli said.

Pettinelli cautioned that researchers hesitate to call the signal an underground "lake," but at the same time they are confident there is water in the sediments because they considered and discarded other hypotheses.

RELATED: The Case for Sending the Search for Life on Mars Underground

For example, they considered that there could be a carbon dioxide or water ice layer within the zone that could affect the reflections, but this was rejected "because of the very specific and unlikely physical conditions required, or because they do not cause sufficiently strong basal reflections," the researchers wrote. The research was led by Roberto Orosei, a researcher with the National Institute of Astrophysics, in Rome.

Another ground-penetrating radar is aboard NASA’s Mars Reconnaissance Orbiter, called SHARAD, which is short for “shallow radar.” SHARAD has been observing the subsurface of Mars since 2006. NASA's website says SHARAD is designed to see up to 4 km (2.5 miles) under the surface, which would include the zone where Mars Express detected signs of water.

While Pettinelli said SHARAD's radar uses too high a radar frequency to see the signal, another researcher had a another take.

Mars researcher Ali Bramson is a graduate associate at the Lunar and Planetary Laboratory in Tucson. In 2015, she led a Geophysical Research Letters paper that used SHARAD data to find an ice sheet in Arcadia Planitia in the northern hemisphere of Mars.

Bramson said the Mars radar community remained curious about why SHARAD didn’t detect water below the south pole.

“Additional studies will be needed to understand why this is the case,” she said, “but I think the case for liquid would have been stronger if both radars had detected a similar signal.”

RELATED: NASA’s Curiosity Rover Detects Methane and Organic Material on Mars

She said the lower frequencies of the MARSIS radar are better for penetrating deeper into the ice and looking at the base of the icy deposits at the poles. However, SHARAD's signal should still be able to look at the same zone.

In research published in 2011, SHARAD identified several spots in Planum Australe that have little or no reflectivity, which are called reflection-free zones. Coincidentally, one of these zones lies right over the new study area where the strange signal was found, Bramson said. But she cautioned that the signal was "very close to the limit of SHARAD's penetration depths."

Bramson said better understanding of the water ice layers and sequestered carbon dioxide in the south polar cap of Mars, which affect radar signals, could help clarify what lies below the surface.

While Bramson did not immediately interpret the signal as necessarily one of water, she said the potential would be interesting for life.

"If it does turn out that liquid water is the only explanation for the radar signal,” she said, “it would be an exciting result, as the subsurface can also provide shielding from the harmful radiation of space, which would be needed if there is any life on Mars given the present lack of a thick atmosphere and magnetic field to protect the surface like we have on Earth.”

Possible traces of life may lie just centimeters below the moon’s icy surface.

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Credit: NASA/JPL-Caltech/SETI Institute

Finding life on Jupiter’s icy moon Europa might not be as difficult as previously thought.

Europa has been one of the top contenders for extraterrestrial life, primarily because of its subsurface ocean. Approximately 100 kilometers deep, the ocean might be in contact with a rocky seafloor that is rich in the elements and energy needed for sustaining life.

Getting a probe down to that ocean might be problematic, though, since Europa is encased in a dense, ice shell perhaps 25 km thick. Planetary scientists have bandied about concepts of complicated drills to get a submarine-like craft down to the ocean.

But, according to new research published in the journal Nature, microbes or other traces of life on Europa might be found just below the icy surface even though the moon is blasted by radiation from Jupiter that can break down organic materials.

“Even in the harshest radiation zones on Europa, our results show that it would be sufficient to simply ‘scratch the surface,’ i.e dig to 10-20 centimeters, to reach material that has not been heavily affected by radiation,” lead author Tom Nordheim from Caltech told Seeker.

Nordheim and his colleagues modeled the effect of energetic particles impacting Europa’s surface and then calculated estimates from laboratory data on how quickly radiation destroys amino acids. They found that that at mid-to-high latitudes, Europa’s ice provides enough protection — acting as a shield against the radiation — that amino acids could persist at detectable levels just 1–3 cm below the surface, even over a 10-million-year time scale.

At the more irradiated equatorial regions, however, the protected depth would increase to several tens of centimeters.

The environment around Jupiter is intense with radiation, as charged particles are trapped in the giant planet’s magnetosphere and form powerful radiation belts. These belts are similar to Earth's Van Allen belts, but are many millions of times stronger.

Credit: NASA/JPL-Caltech/Samuel M. Howell

The new research shows that life could survive on Europa’s surface, but how might it have gotten there in the first place?

While scientists have been pondering a subsurface ocean on Europa since NASA's twin Voyager probes flew by Jupiter in 1979, more recent research has shown that the ocean may actually shoot up to Europa’s surface.

The icy moon is covered with cracks and fissures, and observations from the Hubble Space Telescope and the Galileo mission have shown that some of these cracks had separated. Dark, icy material appeared to have flowed into the opened gaps. In 2016, Hubble also found evidence of plums of water vapor being expelled from the ice surface of Europa.

Kevin Hand from NASA’s Jet Propulsion Laboratory, who also participated in the research, has long been studying Europa. In a 2013 paper co-authored with planetary science Mike Brown, Hand concluded that the surface of Europa might “taste” a lot like ocean water here on Earth — infused with salts, such as magnesium sulfates. If there is a chemical exchange between the ocean and surface, it would make for a rich chemical environment.

RELATED: A 12-Mile-Wide Body of Water May Lie Below the South Pole of Mars

Another way that life-sustaining materials could have been introduced to Europa’s icy surface is through a process called meteoritic gardening, or impact gardening.

“The basic idea is that on an airless world like Europa, or the moon, small meteor impacts mix and churn the surface, much like digging in a garden,” said Cynthia Phillips of NASA’s Jet Propulsion Laboratory, who was not involved with the recent research, but has been very active in studying Europa.

Over time, Phillips said, a random distribution of small and large impacts take place, and varying amounts of different material gets mixed together. While impact gardening definitely takes place on Europa, she added, scientists don’t have a good measurement of impact frequency and so can’t say for certainty how deep the layer of surface material might be.

Meteoritic impacts over a 10-million-year timescale would expose and mix materials from shallower depths that had been exposed to more intense irradiation with material from greater depths exposed to less irradiation, lessening the effect of the ice’s protection.

But the ice and minus 300 degree Fahrenheit temperatures at Europa’s surface provide a shield. Laboratory studies conducted  by Nordheim and his colleagues found that amino acids contained within water ice at low temperatures display “substantially reduced destruction rates,” according to their paper.

RELATED: Twelve New Moons Discovered Orbiting Jupiter

The only way to definitively find out about potential life on Europa, however, is to go there — and NASA has plans to do just that.

The Europa Clipper mission is an orbiter tentatively set for launch in the early to mid-2020s. The spacecraft would conduct a series of flybys of Europa. With a suite of instruments, the mission aims to confirm the presence of the subsurface ocean, characterize its makeup, and study  the processes of surface-ice-ocean exchange. And NASA is also studying concepts for a Europa lander mission, which would launch after Europa Clipper.

Phillips said one concept submitted by her and a group of colleagues includes instruments like an organic chemistry analyzer, a vibrational spectrometer, a microscope, a camera, and a seismic analyzer.

“Instruments like these, working together,” Phillips said, “should be able to give multiple lines of evidence for whether or not biosignatures can be found just beneath Europa’s surface.”

Seeker’s Bad Science podcast examines the efficacy of nuking a Texas-size asteroid on a collision course with Earth.

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An asteroid the size of Texas is plunging toward Earth, heralded by a barrage of meteors that rip the crown off the Chrysler building and smash Paris and Shanghai as well.

In a desperate effort to save the planet, NASA grabs a hotshot drilling crew off an oil rig, gives them a couple of days of training as astronauts, and sends them into space to bore into the rock and blow it up, armed with a nuclear bomb and an Aerosmith power ballad.

That’s how it goes down in Armageddon, the 1998 blockbuster with an all-star cast that includes Bruce Willis, Steve Buscemi, Liv Tyler, and Ben Affleck. But if we actually found ourselves on a cosmic collision course, how closely would life imitate art?

In this week’s episode of Seeker’s Bad Science podcast, host Ethan Edenburg, comedian Riki Lindhome, and guest scientist Varoujan Gorjian, an astrophysicist at NASA’s Jet Propulsion Laboratory, dig into what Armageddon got wrong — and occasionally right.

First off, would nuking a giant space rock headed for Earth save us all, or just make things worse?

According to NASA, which observes and tracks near-earth objects, no known asteroid or comet poses a significant risk to Earth for more than 100 years. But if a new one were to pop up on the radar, Gorjian said, using rockets to nudge it onto a different course would be a better option than blowing it up.

“Blowing it up generally is a bad idea, because it’s going to split it up into multiple pieces, and many of those pieces will hit,” he said. But “The earlier you know, the easier it is to deflect it.”

“If you know about it earlier enough you can actually fly a rocket that hits it and has this gentle thrust and just slowly nudge it,” Gorjian said.

RELATED: Inspiration and Ichthyology: The Science of Finding Nemo

Of course, in the movie, the killer asteroid wasn’t spotted until 18 days before impact — which Gorjian called “ridiculous.” And while the mission-control chatter and the procedure around the launches were realistic, launching two manned missions nearly simultaneously would be highly unlikely.

But while the other guests lacerate the movie, Mara Tsudis — a construction engineer with experience working in oil refineries — praises its working-class hero message. “I love when normal people get to save the day,” she said. And unlike Deep Impact, the other death-from-above blockbuster that came out the same year, “Nobody was bored watching this movie,” Gorjian said.

Why train oilworkers to be astronauts when you can just train astronauts to run a drill? Why risk astronauts at all? And who let Buscemi’s favorite stripper into the landing site? Hear Ethan, Riki, Varoujan, and Mara tackle those questions and more in the latest episode of Bad Science — and stick around for a duet between Riki and Ethan.  

Severe storms have disrupted the long-distance swimmer's progress, but Lecomte is as determined as ever to forge ahead with his historic trans-Pacific journey.

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Credit: Seeker Media

Becoming the first man to swim across the Pacific Ocean from Tokyo to San Francisco was never going to be easy. Over the past two months of this perilous campaign for ocean conservation and science, Ben Lecomte and the crew aboard Seeker have faced rough seas, seasickness, nausea, and a constant stream of plastic. The 51-year-old swimmer has still doggedly progressed more than 500 miles, pushing forward eight hours daily against a parade of hurdles.


Now two typhoons, Jongdari and Wukong, have interrupted his momentum and forced the ship to head back to port in Japan — a development that reflects the difficulty of the journey and the unpredictability of the ocean.

Tropical storm Jongdari had already created hazardous swimming conditions along Japan’s eastern coastal waters when it became a hurricane-strength typhoon as it approached Japan this weekend, hitting the island nation with winds of up to 110 mph and cutting off electricity to more than 158,000 households. At least 24 people have been reported injured. Wukong has meanwhile been churning the ocean northeast of Japan.

Putting his frustrations into perspective while maintaining a rock-solid mindset has become a routine exercise for Lecomte. He accepts that the weather is beyond his control, and he remains focused only on factors that he can influence.

“The weather, there’s nothing I can change about it,” he remarked. “I’m not going to stress about it. I’m not going to put thought into it. It is what it is, and that’s all.”

Maks Romeijin, the crew’s medic, said that Ben isn’t a person that succumbs to mishaps.

“He’s physically and mentally ready for the challenge, no matter what stands in his way,” he said.

RELATED: Introducing ‘The Swim’: A 5,500-Mile Expedition Across the Pacific Ocean

Lecomte set off on this treacherous 5,500-mile voyage across the Pacific on June 5. The aim of his six-month-long swim is to raise awareness about the state of world’s oceans. Along the way, Lecomte and his crew will collect data and conduct experiments that will help researchers better understand conditions in the Pacific, including the Great Pacific Garbage Patch.

The garbage patch is an area of plastic pollution in the Pacific gyre system that spans more than 600,000 square miles. The gyre’s vortex has collected a diffuse stew of plastics that has grown to become the largest of several offshore plastic accumulation zones around the world.

The waste ranges in size from tiny microplastics that are less than 5-millimeters long to larger objects like bottles, crates, and fishing nets. A recent study estimates that this region could hold upwards of 80,000 tons of ocean plastic.

But plastic isn’t confined to the garbage patch. Pollution has spiraled into a crisis threatening the world’s ocean ecosystems, and The Swim team has seen distressing evidence of this in the water every day.

“The trash is way worse than we thought it would be,” said María Amenabar, a research assistant on the crew who has collected samples along the route. “We have to get back out there and keep going.”

Credit: Seeker Media

Spending hours in the water daily, Lecomte has been up close and personal with the impact that pollution is having on sea life.

“It’s more important now than ever that we make it to the Great Garbage Patch,” he said. “I want to show people why our oceans are so important.”

Traversing Earth’s largest body of water takes energy, and Lecomte consumes 8,000 calories a day in order to fuel his grueling swimming routine. Ben plunges into the ocean at around 8:00 am each day. During his time in the water, he eats only soup and bread that is prepared at 4:00 am by Yoav Nevo, who is also the boat’s skipper.

The adventure also takes courage and resilience. Bouts of motion sickness and dropping into the cold waters of the Pacific each day test not only Lecomte's physical abilities, but also his mental endurance. 

Although he is swimming along the Kuroshio Current, which flows northward from the west side of the North Pacific, he’s had to endure unfavorable swimming conditions throughout his expedition.

“I’ve never been in a situation yet where I’ve had the wind and the waves in my favor,” he said. “When I swim, I like to have the waves going in my direction, with me, and also the wind to go in the direction I swim. I’ve never been in that situation yet.”

RELATED: Follow Ben Lecomte's Journey Across the Pacific Ocean

As if fighting the forces of the world’s fiercest ocean isn’t enough, the path along which Lecomte is swimming is also a major international shipping channel. Fourteen days into the swim, a large tanker came precariously close to Ben while he was in the water. The crew contacted the ship, offering GPS coordinates in order to avoid a mishap.

Lecomte is an experienced long-distance swimmer. In 1998, he swam across the Atlantic Ocean from Massachusetts to France, with a one-week stopover in the Azores. Like his current swim, which aims to raise awareness about ocean conservation issues, his Atlantic effort also had a social purpose: to raise awareness about cancer following the death of his father.

In the water, swimming among the ocean’s wide array of species, Lecomte reflected on the majesty of the Pacific ecosystem.

“You don’t feel like you’re in pain anymore,” he said. “You feel very privileged and honored to be in that space and realize that there are many, many things that we don’t know — many, many things that we haven’t experienced and are magical and beautiful.”


The SpaceX and Tesla CEO said, despite recent research findings, that enough carbon dioxide could be harvested on Mars to make it habitable for humans.

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Credit: NASA, ESA, and STScI

Our dreams of making Mars habitable for humans might have to wait a while. 

The Red Planet lacks sufficient sources of carbon dioxide to make the planet more Earth-like using currently available technology, according to new research published in the journal Nature Astronomy.

Researchers reviewed 20 years of Mars observations, gathered from orbiting spacecraft and surface rovers, with the goal of determining how much carbon dioxide is available for terraforming, the process by which humans might engineer the planet’s atmosphere in order to sustain life.

Terraforming the Martian atmosphere, so the theory goes, would require tapping CO2 stored in sources on the surface and below-ground, like rocks and the planet’s frozen ice caps. Carbon dioxide is a greenhouse gas, and greater amounts of greenhouse gases in the atmosphere of Mars would increase atmospheric pressure, warm the planet, and allow for liquid water to remain on the surface.

But researchers found that harvesting readily available CO2 sources with currently available technologies might only warm the planet by 10 degrees Celsius, far too little to make the frigid air of Mars habitable.

"In the popular press, we often read about how easy it is to terraform Mars,” principal investigator Bruce Jakosky, a geologist at the University of Colorado, Boulder, told Seeker. “You know, it's not as easy as people would think."

But don't tell that to Elon Musk.

Credit: NASA Goddard Space Flight Center

The Martian atmosphere was once a lot thicker than it is today, according to observations from NASA’s Mars Atmosphere and Volatile Evolution Mission — MAVEN for short. But charged particles from the sun knocked away some of the lighter isotopes of argon and other molecules. These molecules are like a lid on the upper atmosphere. When present, they keep other gases circulating at lower altitudes. But in their absence, it's easier for the atmosphere to escape into space. What's left is a very thin atmosphere.

Recent observations from the European Space Agency’s Mars Express spacecraft showed in the most detail yet how in warm weather, water circulates from the Martian polar caps into the lower atmosphere, which is in turned coupled to the more tenuous outer atmosphere that slowly leaks into space. In cold weather, water in the atmosphere freezes out and lands again on the caps. The cycle is complex, researchers said, but their work showed that the atmosphere of Mars "behaves as a single system."

RELATED: A 12-Mile-Wide Body of Water May Lie Below the South Pole of Mars

Scientists searched for decades for the presence of carbonates on the surface of Mars. Finally, in 2008, NASA’s Mars Reconnaissance Orbiter (MRO) found deposits of magnesium carbonate in Nili Fossae, a zone that is near one of the planet's largest impact basins. Both MRO and the space agency's Mars Odyssey have observed carbon dioxide in the planet’s ice caps, which could be another possible source for warming up the atmosphere.

The authors tallied the inventory of CO2 stores on Mars, which for the most part include the caps and Nili Fossae. They found that CO2 in the soil would require either strip mining or a large amount of heating to release into the atmosphere. The massive ice caps would basically have to be evaporated completely to remove their carbon stores.

Their conclusion is surely a letdown for advocates of terraforming Mars: For all the effort, there’s just not enough carbon available to trigger the necessary atmospheric changes to support life.

"People at first thought there must be a lot of carbon dioxide [on the surface], because of Mars's thicker atmosphere in the past," Jakosky told Seeker. "But we haven't been able to identify very much."

He said even the Nili Fossae carbonate plains — the single largest source of carbon on Mars — have tough rocks that would make it difficult to harvest the CO2 on a large scale.

Jakosky acknowledged, though, that future innovations might improve the chances for terraforming Mars.

The best method for advancing our knowledge of CO2 inventories on Mars would be a sample-return mission. Luckily, both NASA and Europe's future rovers — called Mars 2020 and ExoMars — are targeted for areas where there might be abundant carbon in Martian rocks.

The new research hasn't squelched dreams of making Mars habitable.

In a tweet, SpaceX and Tesla CEO Elon Musk — a longtime proponent of Mars exploration — said he disagrees with the conclusions of the new study. "There’s a massive amount of CO2 on Mars adsorbed into soil that’d be released upon heating. With enough energy via artificial or natural (sun) fusion, you can terraform almost any large, rocky body," he said.

Seeker’s Bad Science podcast examines James Cameron’s deep-sea classic The Abyss.

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The water’s not so fine in The Abyss.

A close encounter with a mysterious force sends an American missile submarine plunging into a rift in the Caribbean Sea floor. An experimental undersea drilling rig gets commandeered to find the lost sub. The crew finds an alien life form at the bottom of the trench. A Navy SEAL officer on board starts cracking under pressure and tries to steal one of the lost sub’s nukes to blow up the aliens. There’s also a hurricane, a Cold War standoff, a love story … and did we mention aliens?

In the latest edition of Seeker’s Bad Science podcast, host Ethan Edenburg takes a deep dive into James Cameron’s 1989 deep-sea mash-up of The Day the Earth Stood Still and Dr. Strangelove. Joining him in the cramped quarters of the show are comedian Kurt Braunohler, an avid fan and diver, and Cal State Long Beach biologist Douglas Pace, who guides us through the science behind the cinema.

“There’s been nothing else made really like it,” Braunohler says.

In this episode, Pace — a veteran of dives in the venerable research sub Alvin — talks about what’s involved in booking that vessel. Pace and Braunohler discuss why free-divers breathe rapidly in and out before hitting the water and whether the experimental breathing fluid Ed Harris uses is really a thing. (Sort of.)

It turns out there really is such a thing as high-pressure nervous syndrome, a complication faced by deep-sea divers — though it’s more likely to cause sudden motor and neurological problems than to make someone slowly go all Sterling Hayden. “If you don’t do something about it pretty quickly you’ll succumb and die from it,” Pace said.

And could Mary Elizabeth Mastrantonio really be revived after intentionally triggering hypothermia and going 10 or 15 minutes without breathing? Maybe, but she probably would have “severe brain damage” as a result.

RELATED: I Wanna Rock: The Science of the 1998 Blockbuster Armageddon

Cameron, who also created the Terminator franchise and made the mega-blockbuster Titanic, is an accomplished amateur explorer in real life. In 2012, he piloted a submersible he commissioned and helped design into the deepest spot in the oceans, the Marianas Trench. His drive for accuracy took a toll on the cast, who had to learn to dive and spent several hours a day underwater in the grueling six-month shoot. And Cameron would refine the visual effects he used to create the aliens to produce the then-stunning “liquid metal” in Terminator 2: Judgment Day a few years later.

What sea creature most closely resembles the aliens? What made Mastrantonio stomp off the set of one of the movie’s most intense scenes? And can Kurt tell real subsea outposts from ones Ethan made up? Hear those questions and more answered in this episode of Bad Science.


Seeker’s Bad Science podcast examines the 2011 hit film starring Bradley Cooper.

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Dumped by his girlfriend, behind on his rent, struggling to finish his novel, writer Eddie Morra gets a break in the form of a pill that lets him put more of his brain to work. His newfound abilities allow him to wrap up his novel in record time and make a killing in the stock market — but they also get him embroiled in a whirl of corporate intrigue and tied up with a murderous loan shark.

In this episode of Bad Science, host Ethan Edberg and his guests take on the 2011 film Limitless, starring Bradley Cooper, Abbie Cornish, and Robert De Niro in a kind of cautionary tale for the age of Adderall. Joining him on the show are Teagan Wall, a behavioral neuropharmacologist and science communicator, along writer-producers Dave King and Steve Hely from The Great Debates.

“I don’t love Limitless, but in terms of movies about people who get smarter, it’s not one of the worst ones,” Wall said. “At least it’s not Lucy.”

The plot kicks into high gear with a longstanding myth about how little of your brain’s capacity you actually use. If you’re just scraping by at 20 percent, wouldn’t being able to draw on more of that grey matter give you an advantage? Not necessarily. Wall said different parts of the brain control different processes, and it all gets put to work at some time or another.

“The fact is you use 100 percent of your brain,” she said. “If you used it all at once, you would have a grand mal seizure and die.”

Limitless went on to inspire a TV show of the same name, in which a character uses his expanded brainpower to help solve crimes. But the film was a great test of Bradley Cooper as a movie star, King said: “It’s not the best story, but I kind of kept watching because of him.”

Bad Science: Gettin’ Pruney With The Abyss

And Wall said Eddie’s ups and downs can be seen as metaphor for bipolar disorder, which can produce episodes of intense, manic energy followed by a plunge into depression and lethargy. When Cooper’s character says “I just felt clear,” that’s “exactly what a manic episode feels like,” she said.

What products actually do — and don’t — boost your brainpower? Would mastering piano, foreign languages, and finance in a matter of days make you kind of a jerk? Can you take a drug by drinking the blood of someone who’s already on it? Hear the guests debate those questions and discover Ethan’s grandmother’s favorite movies in the latest episode of Bad Science.

Of the thousands of known exoplanets, Kepler-452b has the most ideal combination of UV light exposure and conditions for liquid water.

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Credit: NASA/JPL-Caltech/T. Pyle

Scientists have been hard at work the past several years identifying potentially habitable exoplanets. There is the rocky world found around Proxima Centauri. Then there’s the rocky planet orbiting Ross 128, which, at 11 light-years from us, is just a small jump away in celestial terms once we figure out how to travel at speeds approaching the speed of light. And NASA's venerable Kepler Space Telescope found a slew of other rocky worlds during its time peering at the sky

But a new study narrows down the dozens and dozens of exoplanets that might support life to just one — Kepler-452b. It's in the sweet spot near its star,  a zone warm enough for water to flow on the surface, yet far enough away that UV radiation from its star won't kill possible life.

"There are many planets within the liquid-water habitable zone. However, it turns out that there is only one near-Earth-sized planet that lies definitively within both the habitable zone and [UV-friendly] zone:
Kepler-452b," study leader Paul Rimmer, a post-doctoral researcher at the University of Cambridge, said in an email to Seeker.

The research was published in the journal Science Advances.

Credit: NASA/JPL-CalTech/R. Hurt

The researchers began their search not by looking at distant stars, but by examining the building blocks of life on Earth. The origins of the new work came from a 2015 study examining what would happen when meteorites laden with carbon hit the atmosphere of the young Earth.

When the carbon in the meteorite reacted with the nitrogen of Earth's atmosphere, a rain of hydrogen cyanide fell to the surface. A series of chemical reactions — fueled by the sun's UV light — created the building blocks of RNA, an essential building block for life.

Rimmer's team wanted to see how quickly these chemical reactions would happen. Using UV lamps in a laboratory, they radiated hydrogen cyanide and hydrogen sulfite ions in water — a method known as "light chemistry." They even tried running the same experiment in the dark, without the benefit of UV light. The chemical reactions in the dark are known as "dark chemistry."

"There is chemistry that happens in the dark: It’s slower than the chemistry that happens in the light, but it’s there,” co-author Didier Queloz of Cavendish Laboratory said in a statement. “We wanted to see how much light it would take for the light chemistry to win out over the dark chemistry.”

RELATED: Astronomers Discover ‘Cosmic Treasure’ Around Exoplanet WASP-107b

The researchers found that in the dark, an inert compound was produced — one that couldn't be used to forge the building blocks of life. But the researchers did see the building blocks form under ultraviolet light.

With a better understanding of light versus dark chemistry, the researchers then turned to the stars. They looked for information about the UV light produced by different stars, and how much light would fall upon planets orbiting them.

"We compare the UV light of the stars to how much UV light is needed for the light chemistry to win," Rimmer said. He added that the winners tended to be warm and hot stars. Cooler stars, like the red dwarfs orbited by the planets Proxima Centauri b and Ross 128b, would need flares to produce enough UV chemistry, but not so strong as to wipe out life on the surface.

And so far, just one planet appears to fit the criteria for UV light and habitability: Kepler-452b.

Rimmer cautioned the search is just beginning, though. The Kepler Space Telescope is low on fuel and nearing the end of its lifespan. But NASA just launched a successor mission called TESS (Transiting Exoplanet Survey Satellite). The satellite will scour the sky for planets orbiting bright and nearby stars. So it may find even more worlds with the right combination of conditions for supporting life.
 

The microgravity of space provides an ideal setting for experiments on bone loss.

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Every three seconds, a person somewhere in the world breaks a bone due to osteoporosis — a progressive disease that decreases bone density, making bones weak and fragile. Osteoporotic fractures greatly reduce quality of life, and immobilization following a fracture can lead to further bone loss which puts these patients at risk for breaking another bone.

When SpaceX CRS-11 launched to the space station last June, it carried 40 mice to the ISS National Lab for a mission aimed at improving treatment for the millions of people with osteoporosis back on Earth. The Rodent Research (RR)-5 mission successfully proved the robustness of a new potential osteoporosis therapy based on a naturally produced protein, NELL-1, and also led to significant improvements in the delivery of the therapy.

Most current osteoporosis drugs only work to slow bone breakdown, not form new bone. A therapeutic approach using NELL-1 being developed by a group of researchers at the University of California, Los Angeles (UCLA) works both ways. NELL-1 has been shown to not only to help prevent further bone loss but also build new bone to replace what was lost. Such a therapy would be of tremendous benefit to patients with severe osteoporosis.

To further evaluate the effectiveness of NELL-1, the UCLA team, led by principal investigator Chia Soo, tested its therapeutic use in mice onboard the ISS National Lab. Microgravity has been shown to induce accelerated bone loss in mice at rates that exceed those caused by either post-menopausal or disuse osteoporosis on Earth, making space an ideal environment to study osteoporosis therapies.

“Testing in microgravity is a huge deal because it induces an extreme state of bone loss,” said RR-5 co-investigator Jin Hee Kwak. “If NELL-1 was found to be successful in a microgravity model, then it may work for the most extreme cases of bone loss on Earth, and that would prove the rigorousness of our therapy.”

Linking Nell-1 and Bone Formation
NELL-1 is a protein made by the body, and its bone-forming effects were originally discovered more than 20 years ago by craniofacial orthodontist and RR-5 co-investigator Kang Ting. He had been examining children with a condition that causes an overgrowth of bone in the skull and wondered whether looking at gene expression in these patients could reveal a protein involved in bone growth.

Ting said, “The question was, can we find a way to see what induces bone formation in patients with too much bone? Can we find the protein and use it to help people who need bone?”

After screening millions of genes, Ting found one protein — NELL-1 — that was overexpressed in children with skull bone overgrowth, leading him to begin investigating NELL-1 as a bone-forming agent. Following results from an independent research group that linked the underexpression of NELL-1 in patients to low bone density, Ting and his UCLA colleagues found that mice lacking NELL-1 exhibit symptoms of osteoporosis as they age.

Credit: RR-5 UCLA Team

In several animal models, the UCLA team was able to demonstrate the use of NELL-1 as a successful osteoporosis treatment; however, use of the protein as a therapy was possible only via local administration. In other words, the NELL-1 protein would have to be injected directly into a patient’s affected bone during surgery.

To make NELL-1 more useful for patients with osteoporosis, the team needed to modify NELL-1 to administer it systemically. This type of therapy could be given as a quick injection under the skin to build bone throughout the body.

As the UCLA researchers began working to modify NELL-1 for systemic use, they submitted a proposal to test the therapy in the microgravity environment on the ISS National Lab and were awarded a CASIS grant, which supported the RR-5 mission. Once modification of the molecule was complete, the team could launch their investigation to the space station.

Modifying the Molecule
Developing NELL-1 into a systemic therapy that could be given as an injection every couple of weeks to build bone would greatly benefit patients; however, modifying the molecule to achieve this was no easy task. The team needed to find a way to keep the therapeutic protein molecules circulating in the blood long enough for NELL-1 to induce bone formation. The molecules also needed to be able to successfully and exclusively attach to bone tissue to be effective and safe.

Additionally, ISS crew members have typically accessed mice on the space station once every 14 days, so the interval between injections had to be at least that long. Keeping NELL-1 in the bloodstream for such a long period was a tremendous challenge. Moreover, with such a long circulation time, the team needed to reduce any toxicity so that the therapy would be safe.

“We tried to modify the molecule so instead of just blindly circulating in the blood, it became kind of a targeted molecule that seeks bones and attaches to them,” Ting said. “This increases efficacy in the bones and reduces toxicity in organs where we do not want the molecule.”

Credit: NASA

With the help of Benjamin Wu, RR-5 co-investigator and former chairman of the UCLA Department of Bioengineering, the team modified NELL-1 using a method called PEGylation, which slows the rate at which molecules are degraded by the liver. This would keep NELL-1 circulating in the bloodstream longer. Then, to help NELL-1 find bone tissue, the team attached the protein to an inactive form of a bone-seeking molecule called bisphosphonate.

The team tested the modified molecule, called BP-NELL-PEG, in a ground-based experiment using female mice whose ovaries had been surgically removed to induce osteoporosis. The team found that injection of the therapy into the abdomen of the mice once every 14 days was successful.

Developing the therapy with a 14-day injection interval was one of the greatest technical challenges the team faced, but successfully extending the dosing interval will also be a substantial benefit to patients, Kwak said. Patients would need fewer injections of BP-NELL-PEG compared with most current osteoporosis drugs. This would not only save extra trips to the doctor’s office, but also make the therapy more affordable.

“Our work on the RR-5 mission really helped us make the delivery more effective and targeted, and it significantly increased the eventual clinical feasibility of the therapy,” said RR-5 principal investigator Chia Soo. “If you have an easier way to deliver the therapy and if you don’t have to deliver it as frequently, it has a much greater human application.”

Having successfully optimized the molecule and achieved the 14-day injection interval necessary for rodent research on the space station, the team was now ready to test the systemic therapy in the extreme case of microgravity-induced bone loss.

Sending Mice to the Space Station
SpaceX CRS-11 launched to the space station last June with the RR-5 mission, carrying 40 female mice aged to 8 months, which is when they reach skeletal maturity. An additional 40 mice remained on the ground at NASA’s Kennedy Space Center as a control group. In both the flight and ground groups, half the mice received BP-NELL-PEG treatment and the other half did not.

The RR-5 mission was unique in that halfway through the nine-week investigation, 20 mice in the flight group (10 receiving treatment and 10 not) were returned to Earth alive to complete the rest of the experiment on the ground at UCLA. The other 10 mice remained on the space station until the end of the investigation when they were sacrificed, and the frozen specimens were returned on SpaceX CRS-12.
 

Credit: RR-5 UCLA Team

Many analyses can only be performed on live tissues and cells, so live return was important to the RR-5 team. When the SpaceX Dragon capsule splashed into the Pacific Ocean last July with the RR-5 live-return mice, the team was elated to find that all 20 mice were alive and healthy. The team also noticed that the fur of the mice was shiny within a day of live return to UCLA, meaning they had been grooming  — an indication of contentment.

“Our live return involved full survival of the animals, and they were safe, healthy, and happy,” Kwak said. “This is a huge milestone, and the exciting part for our science team is that all of our data will be very reliable.”

Analyzing Data and Looking to the Future
The RR-5 team is still in the process of analyzing all the data, but preliminary results indicate the investigation was a success. Data from the hind limbs and vertebrae of the spaceflight mice showed significant bone loss from microgravity and a remarkable recovery by BP-NELL-PEG treatment.

“We can unequivocally say that NELL-1 increases bone density in microgravity conditions, which is very exciting,” Soo said. “This success demonstrates the robustness of the therapy to treat extreme bone loss.”

RELATED: ‘Bone Glue’ Experiments on the ISS Test Possible Treatment for Osteoporosis

From here, the team plans to probe deeper into the molecular biology of the NELL-1 protein to gain a more detailed understanding of how the molecule works, while continuing to focus on the practical translational aspects of the therapy.

“We want to look at how we can make this a better osteoporosis treatment for eventual clinical application,” Soo said. “Not only for the millions of osteoporosis patients on Earth but also, in thinking about future space travel and a mission to Mars, we want to see how we can prevent the detrimental effects of microgravity on bones during spaceflight.”

Although modification and use of NELL-1 as a therapy has come far since its discovery more than 20 years ago, there’s still a long journey ahead before this treatment approach can be applied to humans, Ting said.

“But that’s what research is about — you have persistence and tenacity, and you never give up,” he said. “Everyone involved in the RR-5 mission was so devoted and committed to making the project successful, and it shows that if we all have the same goal and push forward, we can achieve anything. The sky is not the limit anymore!”

Pumping aerosols into the atmosphere might reduce incoming solar radiation, but it also reduces the amount of available sunlight.

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Credit: Smith Collection/Gado/Getty Images

Tough news from the stratosphere this week: A new analysis of climate change effects suggests that even our Plan B option for heading off catastrophic climate change is unlikely to be effective.

The study, led by scientists at the University of California, Berkeley, was designed to assess the effectiveness of hacking Earth’s climate by injecting sulfate-based aerosols into the atmosphere. The aerosols would reduce the amount of incoming solar radiation and cool the planet.

But according to Jonathan Proctor, lead researcher of the new report, geoengineering probably won't work — at least in terms of preventing crop damage. By crunching the numbers from previous volcanic events and running the data through models of Earth’s climate, Proctor and his team concluded that any improvements in yield from the cooler temperatures would ultimately be offset by reduced amounts of sunlight.

“What we found was that the technology cooled the Earth and that led to increased crop growth. At the same time, however, the technology also reduced the amount of available sunlight at the earth's surface, which reduced crop growth because crops need sunlight for energy,” Proctor said in a video released with the new research. “What this means is that geoengineering may be an ineffective tool to mitigate the damages that climate change poses to agricultural production.”

The study was published August 8 in the journal Nature.

Stephen McNally video, Hulda Nelson graphics
Proctor, a UC Berkeley doctoral candidate in the department of agricultural and resource economics, said that he was surprised by the findings.

“We are the first to use actual experimental and observational evidence to get at the total impacts that sulfate-based geoengineering might have on yields,” he said. “Before I started the study, I thought the net impact of changes in sunlight would be positive, so I was quite surprised by the finding that scattering light decreases yields.”

Credit: University of California, Berkeley

Using data from 105 countries from 1979-2009, the team analyzed maize, soy, rice, and wheat production, along with global satellite observations of atmospheric aerosols, to study the effect varied amounts of incoming solar energy had on agricultural production. Then, using global climate models, the team calculated that the loss of sunlight from a sulfate-based geoengineering program would cancel out the intended effect of protecting crops from extreme heat.

“It’s similar to using one credit card to pay off another credit card,” co-author Solomon Hsiang, director of UC Berkeley’s Global Policy Laboratory, said in a statement. “At the end of the day, you end up where you started without having solved the problem.”
 

Researchers may have finally solved the debate over how the first Americans arrived on the continent.

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Credit: Potter et al., Sci. Adv. 2018;4: eaat5473

An ambitious new cross-disciplinary study promises to at least partially resolve a long-running debate in science. Did the first Americans arrive via an inland land-bridge route, threading their way through ice sheets in modern-day Alaska? Or did they skirt the coastline from Asia to the Americas?

According to the new analysis of archaeological, genetic, and other data, the answer is … both. Probably.

The conclusion leaves a bit to be desired in terms of wager-settling, but according to the research team, it really is the most accurate assessment archaeologists can make at this point.

The findings, if widely accepted, represent a potentially major shift in scientific thinking. For much of the 20th century, it was considered bedrock truth that the first Americans came to the continent via the ice free corridor — or IFC — a route between two massive ice sheets from Asia through the interior of Alaska and finally into the high plains of North America.

But in the last 20 years or so, new data has emerged suggesting that at least some of the very first Americans may have arrived by way of the “kelp highway” — a coastal route from Asia to the western coastline of North America. Emerging consensus on this theory refers to the pathway as the North Pacific Coast route, or NPC.

The authors of the new paper conclude that although the IFC route is more often supported by data, the NPC route is now adequately well-supported too, and both theories should be considered as viable pathways to the Americas.

“I think we’re in a very exciting time where we can’t exclude either coastal or interior route,” study author Ben Potter, a professor of anthropology at the University of Alaska, Fairbanks, said in a conference call with reporters. “Both could be used, actually; I suspect both probably were used.”

The research was published August 8 in the journal Science Advances

Credit: Potter et al., Sci. Adv. 2018;4: eaat5473

Potter, along with co-author David Reich and colleagues, examined multiple previous claims on the subject based on genetic, archaeological, and paleoecological data. In addition to archaeological evidence, the study included analysis of DNA samples taken from indigenous people of North America, as well as lake bottoms, plants, fossils, and bison.  

Ripan Malhi, a professor of anthropology at the University of Illinois, Urbana-Champaign, said that new genetic analysis technologies can open up entirely new avenues of research for solving the abiding mystery.  

“We’re just at the very beginning of learning about what we can use genomic data for to infer information about the peopling [of the Americas],” he said.

RELATED: The ‘Out of Africa’ Story of Human Migration Is Undergoing Major Revision

Potter said that he hopes the new paper will encourage further research of both the IFC and the NPC routes.

“We highlight that really geologically informed surveys and paleoecological work needs to take place in both regions,” he said. “And we shouldn’t be as firm as some have been that we know the answers now.”

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