Gut Feelings

By Bob Holmes | November 21, 2018 1:49 pm
gut-chemosensation-1600x600

Peasants revel at a wedding feast in this classic 1567 work by Dutch Renaissance painter Pieter Bruegel the Elder. Food has long been linked to celebration across many cultures. This holiday season, you’ll be tasting a lot more than you think thanks to the complex role of taste receptors in the digestive process. (Credit: Peter Brugel/Wikimedia Commons)

Every November, millions of Americans tuck into a tasty Thanksgiving dinner, most often a traditional roast turkey with all the trimmings. Come December, they feast all over again. Few of the holiday diners realize, however, that their bodies will continue tasting that meal long after they’ve swallowed it.

Scientists are finding that the same taste receptors lining the tongue and palate also occur in the stomach, intestines and other internal organs. They’re finding new receptors that also sense nutrients in our foods. And the more they investigate, the more they learn that these receptors play a crucial role in coordinating our digestion, regulating what we eat and how much — even orchestrating our immune system to defend against pathogens and parasites. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: nutrition

Meet the Roboticist Making Machines Act Like Animals

By Nathaniel Scharping | November 21, 2018 10:09 am
Manus robots

Participants at the World Economic Forum’s 2018 Annual Meeting of New Champions wave hello to the Manus robots. (Credit: ATONATON)

When I pick up my iPhone and tell it do something, it feels natural. That’s much of the appeal behind Apple devices — the intuitiveness of their interfaces makes it easy for us to translate human thoughts into the language of a machine.

The machines in Madeline Gannon’s latest project sit at the other extreme of this spectrum. The industrial robotic arms are hulking, blocky beasts that gleam in a most un-lifelike way. Their bodies are essentially one long arm, articulated to give the robots a range of motion no living creature could achieve.
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CATEGORIZED UNDER: Technology
MORE ABOUT: robots

A History of All the Times We’ve Sent Missions to Mars and Failed

By Korey Haynes | November 20, 2018 1:04 pm
a lander hovering above the surface of Mars

Mars Insight will touch down on November 26. (Credit: NASA/JPL-Caltech)

On November 26th, NASA’s Insight mission will land on Mars. That’s the plan anyway. Something like half of all Mars missions have failed, usually well before they approached the Red Planet, either because of launch failure or some error on its outward trip. While space agencies’ records have improved, especially over the last decade, Mars is littered with spacecraft that didn’t quite stick the landing — or, in some cases, orbital insertion. Here are some of the highlights.

white static on black background

Mars 3 sent back this first — and its only — image of Mars’ surface. What it saw is anyone’s guess. (Credit: Soviet Academy of Sciences)

First to Fail

The Soviet Mars 2 holds the dubious honor of being the first manmade object to touch Mars. But it did so more roughly than intended. Mars 2 entered the Red Planet’s atmosphere a bit too steeply, likely causing a cascade of bad signals that meant it never released its parachute. The craft plummeted to the ground, and was presumed destroyed. It never made contact with its engineers.

Its sister lander, Mars 3, did make it to the surface in a controlled landing, even navigating through an intense dust storm on its way down. However, the craft only operated for 20 seconds before falling silent, sending back just one uninterpretable image. Still, a win is a win.

Math Error

Perhaps the most infamous failure is the Mars Climate Orbiter’s destruction in 1999. The issue wasn’t even all that technical: One team used English units such as pounds and feet while the rest of the engineers used metric. The real problem is that no one noticed until the spacecraft shot far too close to the planet, burning up in an atmosphere it was never supposed to enter. It remains one of NASA’s more embarrassing mistakes — not least because at least two engineers did notice the discrepancy, and the problem still didn’t get fixed. It was an error that cost a cool $193 million.

Half Successes

Beagle 2 (left) should have unfolded as seen above. Images from NASA's Mars Reconnaissance Orbiter (right) show that instead only a few of its solar panels unfolded as planned. Image Credit: NASA-JPL

Beagle 2 (left) should have unfolded as seen above. Images from NASA’s Mars Reconnaissance Orbiter (right) show that instead only a few of its solar panels unfolded as planned. (Credit: NASA-JPL)

In 2003, the European Space Agency successfully piloted Mars Express into orbit around the Red Planet. In December of that year, the orbiter released its lander component, Beagle 2, for a Christmas Day touchdown. The lander went out of radio contact, and was never heard from again. Scientists assumed the lander had crashed, though they hadn’t received any sign of malfunction.

Then, in 2016, researchers looking over martian satellite photography found the crash site — which wasn’t a crash at all. It turned out the lander had settled, to all appearances, quite gently onto the martian terrain. Its deployed parachute is even visible in some imagery. The problem was its solar arrays, one of which didn’t unfold correctly, leaving the lander unable to send signals back to Earth. Beagle 2 was ultimately tantalizingly close to success, while still completely failing its mission objective.

ESA’s bad luck continued. In 2016, they again succeeded in getting a spacecraft into orbit — this time the Trace Gas Orbiter. Again it released a lander, Schiaparelli. This time, the landing module kept in constant contact with its orbiting partner so that scientists would have a better record of the craft’s descent. This meant they were fully informed when the lander slammed into the Red Planet at 340 mph.

Schiaparelli’s sensors overloaded during a turbulent descent, causing the spacecraft to think it was underground when it was actually still a few miles in the air. In sort-of-rational response, the craft ejected its parachute and only fired its landing thrusters for a few seconds, assuming it was at ground level. It was not. The lander plummeted the rest of the way to the ground. But hey, at least this time engineers knew what had happened.

Triple Failure

artist's depiction of the lander on a red planet

The Mars Polar Lander would have gathered climate data from Mars’ South Pole region. Image Credit: NASA-JPL

The Mars Polar Lander combined both of these problems back in 1999. It was not monitored as it descended, meaning engineers had to offer their best guesses later as to what went wrong. A year later, looking over their equipment, they realized that it was almost certainly the false signals the landing gear sent telling the lander it was on the ground and could stop firing its brakes when it very much was not, and should not. The testing prototype was wired differently and hadn’t experienced this problem, but the one they sent to Mars apparently did.

Adding insult to injury, the Deep Space 2 probes that NASA sent along with the lander also failed — and their job was to crash into the surface, and then report back. The lander’s mother craft dropped off the tiny probes before its own troubles started, and the DS2 probes seemed to release without incident. But they never checked in, leaving engineers to assume that they were not, in fact, capable of surviving the impact they had been designed to undergo.

These are the failures, but Mars has plenty of successes too, especially in recent years. It sounds flip, but space engineers are serious when they say that Mars is hard. It has more gravity than the moon, less atmosphere than Earth to fill parachutes, and it’s far enough away that the maneuvers must be done on autopilot.

Luckily, space agencies have been getting better and better, and we’ve come up with some cool tricks: inflatable cushions, braking thrusters, and sky cranes. That’s good, because we’ve still got big plans for our neighboring planet.

CATEGORIZED UNDER: Space & Physics, Top Posts

The Complicated History of Planets Around Barnard’s Star

By John Wenz | November 19, 2018 4:35 pm
Barnard's star b

An artist’s interpretation of what Barnard’s star b, a super-Earth recently discovered just six light-years from Earth, may look like. (Credit: ESO/M. Kornmesser)

Perhaps no other star system has elicited so much wonder, mystery and frustration as Barnard’s Star.

Astronomers announced last Wednesday they’d discovered a planet in its thrall weighing in at around three Earth-masses, with a frigid, 233-day orbit. The find finally answers whether we have any planetary neighbors in the second-closest system to Earth (after Alpha Centauri). Read More

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: exoplanets

How Would We Save the Planet from a Killer Asteroid?

By Korey Haynes | November 19, 2018 12:48 pm
fireballs streak across a night sky

Meteors are both common and beautiful. But larger impactors can cause devastating harm. (Credit: NPS)

We don’t need to be scared of everything that falls from space. In fact, literal tons of space rocks rain down daily, though that’s mostly in the form of minuscule dust grains. But every 100 million years or so, catastrophe strikes in the form of a rock spanning miles.

The last one killed not just the dinosaurs, but three-quarters of all life on Earth. The effects on humans could be equally devastating — bomb shelters wouldn’t cut it in the face of such an event.

Not when the shaken Earth hurls tsunamis onto every shore. Not when volcanoes explode in angry retort. Not when the skies go dark with the asteroid version of a nuclear winter, dust and debris covering the sun. Even people who survive the first wave of destruction would inherit a world utterly destroyed. The world’s stubbornest creatures, the cockroaches and rats and tardigrades, would probably be fine. But the rest of us are doomed.

It’s a cataclysm of almost unthinkable proportions, but history tells us that it is indeed possible. Thankfully humans today have rockets and nuclear bombs and NASA. We can engineer a way out of this. Read More

CATEGORIZED UNDER: Space & Physics, Top Posts

What Studying Primate Communication Tells Us About The Evolution of Human Language

By Bridget Alex | November 17, 2018 10:00 am
chimpanzees

(Credit: LiaoZhuangDjiu/Shutterstock)

Kanzi is a linguistic all-star among apes. From an early age, the captive bonobo learned over 400 symbols representing words, which he points to, in order to communicate with people. He understands even more spoken English and basic grammar, and followed verbal directions as well as a 2-year-old human during a study conducted in the late 80s.

Having watched Kanzi clips more times than I care to admit, I’m ceaselessly amazed by his communication skills. But still, as the most linguistically talented ape, he’s just on par with a run-of-the-mill toddler. Kanzi may comprehend around 1000 words, but there are over 170,000 in the Oxford English Dictionary. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: evolution, language, primate

Skeletal Studies Show Sex, Like Gender, Exists Along a Spectrum

By Alexandra Kralick | November 16, 2018 1:27 pm
Stanislawa Walasiewicz

Stanislawa Walasiewicz won the gold for Poland in the women’s 100-meter dash at the 1932 Olympic Games. Upon her death, an autopsy revealed that she had intersex traits. (Credit: Wikipedia)

She wasn’t especially tall. Her testosterone levels weren’t unusually high for a woman. She was externally entirely female. But in the mid-1980s, when her chromosome results came back as XY instead of the “normal” XX for a woman, the Spanish national team ousted hurdler María José Martínez-Patiño. She was ejected from the Olympic residence and deserted by her teammates, friends, and boyfriend. She lost her records and medals because of a genetic mutation that wasn’t proven to give her any competitive advantage.

People like Martínez-Patiño have been ill-served by rules that draw a hard line between the sexes. In the U.S., the Trump administration looks set to make things worse. According to a memo leaked to The New York Times in October, the U.S. Department of Health and Human Services is trying to set up a legal binary definition of sex, establishing each person “as male or female based on immutable biological traits identifiable by or before birth.” But our bodies are more complicated than that.

An increasing recognition of this complexity by researchers and the public has affirmed that gender sits on a spectrum: People are more and more willing to acknowledge the reality of nonbinary and transgender identities, and to support those who courageously fight for their rights in everything from all-gender bathrooms to anti-gender-discrimination laws. But underlying all of this is the perception that no matter the gender a person identifies as, they have an underlying sex they were born with. This represents a fundamental misunderstanding about the nature of biological sex. Science keeps showing us that sex also doesn’t fit in a binary, whether it be determined by genitals, chromosomes, hormones, or bones (which are the subject of my research).
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CATEGORIZED UNDER: Health & Medicine, Living World

The U.S. May Ban Kratom. But Are its Effects Deadly or Lifesaving?

By Troy Farah | November 15, 2018 3:00 pm
kratom ground leaves for capsules

Kratom is a drug popular in Southeast Asia that’s derived from the leaves of Mitragyna speciosa, a tree in the coffee family. Kratom’s pain relieving properties allowed it to surge in popularity in the United States in the wake of the opioid crisis. (Rattiya Thongdumhyu/shutterstock)

Across America, thousands of people are throwing away their prescription drugs and picking up kratom, a plant-based drug from Southeast Asia usually brewed as a tea. Within the leaves of this tropical tree are opioid-like compounds that users say provide pain and anxiety relief, and the ability to wean off street drugs like heroin. But some health organizations warn kratom can be addictive itself or even deadly.

An estimated five million people use kratom regularly, according to the American Kratom Association (AKA), a pro-kratom lobbyist group. And the rising popularity of this herb has caught the eyes of federal government regulators, who have made several unsuccessful attempts to ban it. But that may soon change.
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CATEGORIZED UNDER: Health & Medicine, Top Posts

Massive Impact Crater Beneath Greenland Could Explain Ice Age Climate Swing

By Anna Groves | November 14, 2018 1:02 pm
A heatmap shows in green a circular crater depression in a red-and-yellow colored surrounding.

Topography under Hiawatha glacier in Greenland, mapped with airborne radar data (1997 to 2014, NASA; 2016 Alfred Wegener Institute). Black triangles and purple circles are elevated peaks around the rim and center. Dotted red lines and black circles show locations of additional sampling. (Credit: Kjæer et al. / Science Advances)

Most of Earth’s surface has been plotted, mapped and measured. And along the way, scientists have turned up a plethora of craters big and small. But there was always one major crater missing.

12,800 years ago, during the Pleistocene, Earth was warming up from its last Ice Age. Temperatures slowly rose while glaciers retreated, that is, until something major happened that triggered a cold snap big enough to leave its mark on the geologic record. Over the course of just decades – the blink of an eye in geological timescales – the planet cooled somewhere between 3 and 11 degrees Fahrenheit (2 to 6 degrees Celsius). The resulting period is known as the Younger Dryas, a mysterious 1000-year blip in history.

Many scientists have suggested – with evidence – that the Younger Dryas was triggered by a meteorite impact. But others have held out, suggesting that volcanic eruptions or, what seems to be the leading favorite, some sort of massive freshwater flood temporarily disrupted climate cycles based out of the North Atlantic. But the main reason scientists have been slow to accept the impact hypothesis is simple: There’s just no crater.

But research out today in the open-access journal Science Advances suggests that maybe we haven’t looked everywhere.
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The Anthropic Principle: Are the Laws of the Universe Fine-Tuned for Life?

By Korey Haynes | November 12, 2018 1:00 pm
a crescent view of Earth

Our planet teems with life. But are we a fluke, or an inevitability? Credit: ESA

Humans have often looked at the night sky and wondered if there’s anyone else out there. But stare into that darkness long enough, and many wonder instead: how did we get here? What were the odds, in a universe so enormous and chaotic, that humans should have come to exist at all? Is life, let alone intelligent life, such a wildly improbable occurrence that we’re the only ones here? Or are we an inevitable consequence of the laws of physics?

Life exists on Earth (assuming we’re not living in a computer simulation). Therefore, the universe must exist in such a way that we are possible. That’s the essence of the anthropic principle. On the one hand, it sounds tautological. By that, I mean, I’m just saying the same thing twice. But cast another way, it can lead us to important truths about the universe. It means any version of the universe we can fathom has to allow for life to exist at least once. When there are things we don’t understand about the universe — how dark energy works, how the cosmos formed — all our theories have to include the fact that we exist. The universe must allow us.

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MORE ABOUT: cosmology
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