The Most-Distant Solar System Object Discovered

science - Posted On:2018-12-18 02:14:58 Source: slashdot

Rick Zeman writes: Astronomers in Hawaii have discovered the furthest object in our solar system, a dwarf planet aptly named "Farout." This planet is 100 times farther than Earth is from the sun (120 AU from the sun) and is thought to be composed of ice. The object is so far away that researchers estimate it probably takes more than 1,000 years to make one trip around the sun. For reference, Pluto is 34 AU away and takes about 248 years to orbit the sun. Eris, the next most distance object know, is 96 AU from the sun. Read more of this story at Slashdot.

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Junk Food Cravings Linked To a Lack of Sleep, Study Suggests

science - Posted On:2018-12-17 20:44:58 Source: slashdot

An anonymous reader quotes a report from The Guardian: Writing in the Journal of Neuroscience, Peters and colleagues describe how they recruited 32 healthy men aged between 19 and 33 and gave all of them the same dinner of pasta and veal, an apple and a strawberry yoghurt. Participants were then either sent home to bed wearing a sleep-tracking device, or kept awake in the laboratory all night with activities including parlor games. All returned the next morning to have their hunger and appetite rated, while 29 of the men had their levels of blood sugar measured, as well as levels of certain hormones linked to stress and appetite. Participants also took part in a game in which they were presented with pictures of 24 snack food items, such as chocolate bars, and 24 inedible items, including hats or mugs, and were first asked to rate how much they would be willing to pay for them on a scale. During a functional magnetic resonance imaging (fMRI) scan, they were asked to choose whether or not they would actually buy the object when its price was fixed -- an experiment that allowed researchers to look at participants' brain activity upon seeing pictures of food and other items. A week later, the experiment was repeated, with the participants who had previously stayed up allowed to sleep, and vice versa. The results showed that whether sleep-deprived or not, participants were similarly hungry in the morning, and had similar levels of most hormones and blood sugar. However, when participants were sleep-deprived, they were willing to pay more for a food snack than when rested, and had higher levels in their blood of a substance called des-acyl ghrelin -- which is related to the "hunger hormone" ghrelin, though its function is not clear. The fMRI results showed that when sleep-deprived, participants had greater activity in the brain's amygdala (where food rewards are processed) when food images were shown, and a stronger link between the price participants would pay for food and activity in the hypothalamus (which is involved in regulating consumption). Interactions between these two regions increased compared with when participants had slept. Read more of this story at Slashdot.

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Conservation of energy used to parallelize quantum key distribution

Science - Posted On:2018-12-17 15:00:00 Source: arstechnica

It has been a while since I wrote about quantum key distribution. Once a technology is commercially available, my interest starts to fade. But commercial availability in this case hasn't meant widespread use. Quantum key distribution has ended up a niche market because creating shared keys with it for more than one connection using a single device is so difficult.

That may all change now with a very inventive solution that makes use of all the best things: lasers, nonlinear optics, and conservation of energy.

The goal of quantum key distribution is to generate a random number that is securely shared between two people, always termed Alice and Bob. The shared random number is then used to seed classical encryption algorithms.

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Genetic information as self-fulfilling prophecy

Science - Posted On:2018-12-17 14:15:00 Source: arstechnica

If the TV ads are at all effective, plenty of people will be getting the gift of their genetic tests this Christmas. These tests frequently allow people to explore their inherited tendencies toward health problems and, in some cases, may suggest lifestyle changes to ward off future problems—although studies have indicated that few people do.

However, DNA test results can also cause issues that wouldn't otherwise be there. Genetic information can exert a potent placebo effect—or the opposite, the nocebo effect, wherein if you think that something can harm you, it in fact does. And the potency of this effect has not been studied until now.

Some psychologists at Stanford wondered if the perception of genetic risk could actually increase people’s risk, independent of their actual genetic risk. In other words, could simply learning that you have a genetic propensity for something elicit physiological changes akin to really having that propensity, regardless of whether you have it? The team designed experiments to find out.

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Archaeologists reconstruct pre-Columbian temple with 3D-printed blocks

Science - Posted On:2018-12-17 13:00:01 Source: arstechnica

The unfinished temple in a southern valley of the Lake Titicaca Basin in modern-day Bolivia has been a mystery for at least 500 years. Now known as the Pumapunku—"Door of the Jaguar" in the Quechua language—the complex stone structure is part of a sprawling complex of pyramids, plazas, and platforms built by a pre-Columbian culture we now call the Tiwanaku. Construction began around 500 CE and proceeded off and on, in phases, over the next few centuries until the Tiwanaku left the site around 900 or 1000 CE.

When the Inca Empire rose around 1200 CE, they claimed the sprawling ceremonial complex as the site of the world's creation, although they didn't finish the Tiwanaku's temple.

Spanish visitors in the 1500s and 1600s describe “a wondrous, though unfinished, building” with walls of H-shaped andesite pieces and massive gateways and windows carved from single blocks. These were set on remarkably smooth sandstone slabs, some of which weighed over 80 tons. But after centuries of looting, the stones of the Pumapunku are so scattered that not one lies in its original place. The Tiwanaku left behind no written documents or plans to help modern researchers understand what their buildings looked like or what purpose they served.

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Tuesday may deliver a triple-header of big launches to cap 2018

Science - Posted On:2018-12-17 10:14:56 Source: arstechnica

So far this year there have been 106 orbital launches around the world, the most in a calendar year since 1990. That works out to roughly one launch every three days. Now, as we approach the end of this year, the launch industry has a treat for us—potentially three launches in a single day on Tuesday.

For rocket fanatics, this should make for a fun day, especially with some bigger rockets on the launch pad. Here's a rundown on what to expect and the significance of each launch.

SpaceX's final launch of the year, its 21st overall, will be an important one for the company. It is scheduled for 9:11am ET (14:11 UTC) from Cape Canaveral Air Force Station in Florida.

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An early Christmas for rocket fanatics: Three big launches on Tuesday

Science - Posted On:2018-12-17 09:59:57 Source: arstechnica

So far this year there have been 106 orbital launches around the world, the most in a calendar year since 1990. That works out to roughly one launch every three days. Now, as we approach the end of this year, the launch industry has a treat for us—potentially three launches in a single day on Tuesday.

For rocket fanatics, this should make for a fun day, especially with some bigger rockets on the launch pad. Here's a rundown on what to expect and the significance of each launch.

SpaceX's final launch of the year, its 21st overall, will be an important one for the company. It is scheduled for 9:11am ET (14:11 UTC) from Cape Canaveral Air Force Station in Florida.

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Emergence of Lab-Grown Meat Poses New Questions for Religious Leaders

science - Posted On:2018-12-17 09:44:57 Source: slashdot

Lab-grown meat is becoming closer to a reality. But this new technology poses new questions for people who typically avoid meat for religious or ethical reasons. An anonymous reader shares a report: Lab-grown meat has sparked a debate among rabbis in Israel about whether cell-cultured is the same as conventional meat and should fall under the same guidelines for keeping kosher. "There is a disagreement about it and there is a conversation. Also, definitely, there are new questions about lab-meat," says Rabbi Yuval Cherlow, an expert on kosher tradition and bioethics. WSJ has posted a video in which you can hear more from Rabbi Cherlow. Read more of this story at Slashdot.

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The Decline of American Peyote

science - Posted On:2018-12-17 05:14:57 Source: slashdot

dmoberhaus writes: An investigation into the decline of America's peyote, a hallucinogenic cactus that is critically important to the rituals of the Native American Church, the largest pan-tribal religious organization in the U.S. Motherboard spoke with Dawn Davis, a researcher using satellite data to track the destruction of peyote's habitat, as well as Salvador Johnson, one of only four people who is licensed to harvest and sell peyote in the U.S. by the DEA. "In 2011, Davis traveled to the peyote gardens for the first time and met with Johnson," reports Motherboard. "Davis said that Johnson was following many conservation best practices, such as cycling through the areas where peyote is harvested, but this hadn't slowed the steady decrease in the size and quantity of peyote buttons in his harvests. Today, the biggest threats to peyote continue to be rapid land development, poaching, and rooting by feral pigs -- problems that responsible harvesting by peyoteros can't solve." While there has been an increase in the number of indigenous people growing peyote in greenhouses, this is only a temporary solution to the conservation crisis. Davis is advocating for conservation easements or tax breaks for landowners to encourage the protection of peyote. She also said it will be necessary to push for the DEA to reschedule peyote, which is still considered a Schedule I substance that has "no currently accepted medical use." This makes it exceedingly hard for individuals to become licensed peyoteros. Read more of this story at Slashdot.

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A Bright Green 'Christmas Comet' Will Fly the Closest To Earth In Centuries

science - Posted On:2018-12-17 00:14:58 Source: slashdot

On Sunday night, a comet that orbits between Jupiter and the sun will make its closest approach to Earth in centuries. According to Tony Farnham, a research scientist in the astronomy department at the University of Maryland, the comet will appear as a bright, fuzzy ball with a greenish-gray tint. "You've got a one-kilometer solid nuclear in the middle, and gas is going out hundreds of thousands of miles," says Tony. The comet glows green because the gases emit light in green wavelengths. The New York Times reports: The ball of gas and dust, sometimes referred to as the "Christmas comet," was named 46P/Wirtanen, after the astronomer Carl Wirtanen, who discovered it in 1948. It orbits the sun once every 5.4 years, passing by Earth approximately every 11 years, but its distance varies and it is rarely this close. As the comet passes by, it will be 30 times farther from Earth than the moon, NASA said. The proximity of 46P/Wirtanen provides an opportunity to research the tail of the comet and see farther into the nucleus. The comet is visible now but it will shine even brighter on Sunday as it reaches its closest approach, 7.1 million miles from Earth. That may sound really far, but it is among the 10 closest approaches by a comet in 70 years, NASA said. Only a few of those could be seen with the naked eye. Don't worry if you miss the comet on Sunday. It should be just as visible for a week or two because its appearance will change gradually. After it moves on, it won't be this close to Earth again for hundreds, if not thousands, of years. Online charts can help pinpoint its location. Read more of this story at Slashdot.

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No more doubts: Two independent studies confirm LIGO’s Nobel discovery

Science - Posted On:2018-12-16 13:30:00 Source: arstechnica

Just last month, we told you about a small group of Danish physicists who were casting doubt on the original gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO), saying it was an "illusion." The researchers alleged that the collaboration mistook patterns in the noise for a signal. Now Quanta is reporting that two independent analyses have been completed that confirm that detection. This should lay any doubts about the momentous discovery to rest.

“We see no justification for lingering doubts about the discovery of gravitational waves,” the authors of one of the papers, Martin Green and John Moffat of the Perimeter Institute for Theoretical Physics, told Quanta. That paper appeared Physics Letters B in September. A second paper by Alex Nielsen of the Max Planck Institute for Gravitational Physics in Hannover, Germany, and three coauthors, was posted to the physics preprint site last month and is under review by the Journal of Cosmology and Astroparticle Physics.

But some drama still remains. Andrew Jackson, group spokesman for the skeptical physicists at the Niels Bohr Institute in Copenhagen, Denmark, is refusing to accept the results of the two independent groups' analyses. Quanta's Natalie Wolchover writes:

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NASA's Hubble Telescope Discovers An 'Evaporating' Planet

science - Posted On:2018-12-15 02:15:00 Source: slashdot

Researchers at the University of Geneva Switzerland have used NASA's Hubble telescope to find an exoplanet that's evaporating. The exoplanet, GJ 3470b, shows signs of losing hydrogen in its atmosphere, causing it to shrink. USA Today reports: The study is part of exploration into "hot Neptunes," planets that are the size of Neptune, sit very close to their star, and have atmospheres as hot at 1,700 degrees Fahrenheit, says NASA. Finding a "hot Neptune" is rare because they sit so close to their star and tend to evaporate more quickly. In the case of GJ 3470b, scientists classify it as a "warmer" Neptune because it sits farther away from its star. The exoplanet discovered by astronauts is losing its atmosphere at a rate 100 times faster than a previous "warmer" Neptune planet discovered a few years before, according to a study published Thursday in the journal "Astronomy & Astrophysics." The planet sits 3.7 million miles from its star. For comparison, Earth is 92.9 million miles from the sun. Researchers say these "hot Neptune" planets shrink in size and morph into "Super Earths," versions of our planet that are massive and more rocky. Read more of this story at Slashdot.

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Ebola outbreak reaches city of 1 million residents

Science - Posted On:2018-12-14 15:00:00 Source: arstechnica

The Ebola outbreak in the Democratic Republic of the Congo has spread to a city of nearly 1 million residents. There are now 30 confirmed cases and 15 deaths in the city of Butembo reported in the latest update provided by the World Health Organization (WHO). The number of cases in the city center is still low, according to Doctors Without Borders, but that number is rising quickly in more outlying districts and suburbs.

The outbreak, which has been going on since August, has so far resulted in 467 confirmed cases and a further 48 probable cases. More than half of the cases have resulted in death (including those of 17 health workers), while 177 patients have recovered, including a newborn baby.

The rate of transmission is beginning to slow down in Beni, a smaller city approximately 36 miles north of Butembo that has the highest number of reported cases so far. But “the outbreak is intensifying in Butembo and Katwa,” writes the WHO, “and new clusters are emerging elsewhere.”

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Rocket Report: Virgin soars, Falcon Heavy cores on the go, Astra failure

Science - Posted On:2018-12-14 07:29:57 Source: arstechnica

Welcome to Edition 1.29 of the Rocket Report! This week, we send our hearty congratulations to Virgin Galactic, which reached an important milestone Thursday with its first flight above 80km. We also have some good news on the commercial crew front, with multiple flights looking promising for 2019.

As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.

Virgin flies into space (probably). With Mark "Forger" Stucky and C.J Sturckow piloting the vehicle, the VSS Unity vehicle was dropped from its White Knight Two carrier aircraft on Thursday before burning its rocket motor. During that 60-second burn, it reached a velocity of Mach 2.9 and soared to an altitude of 82.68km. These were records for the company, which may begin flying space tourists in 2019.

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When will electric airliners make sense?

Science - Posted On:2018-12-14 06:59:57 Source: arstechnica

Currently, the world is struggling to keep its carbon emissions from rising. But to reach the longer-term goals we have for stabilizing the climate, we're going to have to do far more than roll out some renewable energy. Keeping the earth from warming by 2°C above preindustrial temperatures means a deep decarbonization of our energy use. Which means that we not only have to go fully carbon neutral in generating electricity, but we have to start using those emissions-free electrons to handle our heating and transportation needs.

For things like cars and busses, that process has already started. But there's one weight-sensitive mode of transportation where batteries may not be able to bail us out: air travel. The relatively low energy density of batteries means that you need a lot of them—plus the weight and space they take up—to power an aircraft. For this reason, many people have decided that we'll need biofuels to power air travel. Yet there are companies that are planning on developing electric passenger aircraft.

So who's being realistic? To find out, an international team has done an evaluation of whether battery-powered electric aircraft can become viable and when it's possible they'll reach the market.

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NASA's Jupiter Mission Juno Reveals Giant Polar Storms

science - Posted On:2018-12-14 05:14:57 Source: slashdot

NASA's Juno mission to the gas giant Jupiter has reached its halfway mark and has revealed new views of cyclones at the poles. The BBC reports: As it orbits the planet every 53 days - Juno performs a science-gathering dive, speeding from pole to pole. Its sensors take measurements of the composition of the planet, in an effort to decipher how the largest world in our Solar System formed. Mapping the magnetic and gravity fields should also expose Jupiter's structure. But images from JunoCam -- a camera that was intended to capture images that could be shared with the public -- has already given us some surprising insights. "When we made our first pass over the poles, we knew we were seeing a territory on Jupiter we had never seen before," said Dr Candice Hansen, from the Planetary Science Institute in Arizona. "What we did not expect was that we would see these orderly polygons of cyclones; huge storms - twice the size of Texas." Read more of this story at Slashdot.

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Supernovae May Explain Mass Extinctions of Marine Animals During Pliocene Era

science - Posted On:2018-12-14 02:14:58 Source: slashdot

"The Register has an article on the possibility that a supernova or a series of them could explain a mass die-off of marine animals around 2.6 million years ago," writes Slashdot reader KindMind. From the report: A gigantic supernova explosion may have triggered mass extinctions for creatures living in Earth's prehistoric oceans some 2.6 million years ago, according to new research published in Astrobiology. Marine animals like the megalodon [...] suddenly disappeared during the late Pliocene. Around the same time, scientists [...] noticed a peak in the iron-60 isotope in ancient seabeds. "As far back as the mid-1990s, people said, "Hey, look for iron-60. It's a telltale because there's no other way for it to get to Earth but from a supernova.' Because iron-60 is radioactive, if it was formed with the Earth it would be long gone by now. So, it had to have been rained down on us" explained Adrian Melott, lead author of the paper and a physics and astronomy professor at the University of Kansas. The team believes that a supernova located 150 light years away set of a chain of supernovae bursts and covered the Earth in a shroud of deadly cosmic ray radiation. This was amplified, Melott said, because the Solar System is right on the edge of an area of the interstellar medium called the Local Bubble. The Local Bubble extends about 300 light years across and contains the two main clouds of dust and gas: Local Interstellar Cloud and the G-Cloud. As the supernovae ejected cosmic rays, these beams of energetic particles would have repeatedly bounced off the clouds to create a "cosmic-ray bath" that could have lasted 10,000 to 100,000 years. Some of that radiation such as cosmic ray muons would have leaked onto Earth, and over time it could have led to genetic mutations and cancers [that would have caused animals like the megalodon to die off prematurely]. Read more of this story at Slashdot.

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Neurosurgery Could Spread Protein Linked To Alzheimer's, Study Finds

science - Posted On:2018-12-13 22:44:59 Source: slashdot

An anonymous reader quotes a report from The Guardian: Surgical instruments used in brain operations should be treated to ensure they are not contaminated with proteins linked to Alzheimer's disease, according to scientists who found evidence that they may be spread by certain medical procedures. The researchers urged doctors to decontaminate neurosurgical tools more thoroughly as a precautionary measure to reduce the potential risk of spreading abnormal proteins known to build up in the brains of Alzheimer's patients. Prof John Collinge, director of the Medical Research Council prion unit at University College London, said that while Alzheimer's disease was not contagious, there was a slim risk that harmful proteins that drive the disease could spread through brain surgery and other rare procedures. Read more of this story at Slashdot.

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Virgin Galactic Successfully Reaches Space

science - Posted On:2018-12-13 13:30:00 Source: slashdot

The latest test flight by Sir Richard Branson's Virgin Galactic successfully rocketed to space and back. From a report: The firm's SpaceShipTwo passenger rocket ship reached a height of 82.7km, beyond the altitude at which space is said to begin. It marked the plane's fourth test flight and followed earlier setbacks in the firm's space programme. Sir Richard is in a race with Elon Musk and Jeff Bezos to send the first fee-paying passengers into space. He founded the commercial spaceflight company in 2004, shortly after Mr Musk started SpaceX and Jeff Bezos established Blue Origin. In 2008, Virgin Galactic first promised sub-orbital spaceflight trips for tourists would be taking place "within 18 months". It has since regularly made similar promises to have space flights airborne in the near future. Read more of this story at Slashdot.

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Virgin Galactic just flew to 82.68 kilometers—is this space?

Science - Posted On:2018-12-13 12:15:00 Source: arstechnica

On a clear and cold Thursday morning in the Mojave Desert, Virgin Galactic's White Knight Two aircraft took off. It carried the VSS Unity spacecraft, which on its fourth powered flight sought to make the company's highest and fastest flight ever. It succeeded.

With Mark "Forger" Stucky and C.J Sturckow piloting the vehicle, VSS Unity was dropped from White Knight Two before burning its rocket motor for 60 seconds, reaching a velocity of Mach 2.9, and soaring to an altitude of 82.68km. These were records for the company, which may begin flying space tourists in 2019.

On one hand, it's difficult to get any rocket to fly high and true. Consider that Virgin Galactic was founded in 2004. It had a basic architecture at that time—an air-launched, rocket-powered spaceship based upon a proven design—and ample funding from a British billionaire. It still took 14 years for the company to make its first spaceflight.

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