Jupiter's unusual X-ray auroras - Axios
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Jupiter's unusual X-ray auroras

An infrared image of Jupiter's southern aurora from NASA's Juno spacecraft. Photo: NASA / JPL / Caltech / SwRI / ASI / INAF / JIRAM

Scientists report today they've detected X-ray auroras on Jupiter's southern pole that, unlike Earth's synchronized Northern and Southern Lights, behave independently from their northern counterparts. Exactly how the planet's magnetic field produce its powerful auroras is unknown.

The big picture: Aurora-producing magnetic fields protect life on Earth's surface so scientists want to be able to recognize their various features and processes as they search for places that could harbor life, study co-author William Dunn from University of College London told the Verge.

How they saw it: Using data collected in 2007 and 2016 from two space-based observatories that could see both poles at the same, William Dunn and his colleagues at University College London found Jupiter's southern aurora pulsed every 9-11 minutes whereas the northern one was inconsistent — it flared every 12, 26 or 40-45 minutes — and with varying brightness.

On Earth auroras form when charged particles in the solar wind get pushed to the planet's poles by the magnetic field. There, the particles collide with oxygen and nitrogen in the atmosphere and emit photons that we see as the Northern and Southern Lights. (There are also auroras in infrared light, ultraviolet light and X-ray that we can't see.) Earth's auroras brighten and dim together as the charged particles are pushed to each pole. Unexpectedly, Jupiter's auroras aren't in such unison.

Why it happens: Unclear but one possibility the researchers propose is that when the solar wind hits Jupiter's large and strong magnetic field, the lines vibrate and produce waves. Charged particles — some of which come from volcanic eruptions on Jupiter's moon Io and others from the solar wind — may ride those waves to the poles and collide with the atmosphere in X-ray producing pulses.

What's next: NASA's Juno spacecraft is orbiting Jupiter and sending data about the planet's magnetosphere. Researchers plan to combine that with X-ray observations to see how the aurora are connected to what is happening on the planet and whether the behavior they saw is common or an exception.

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Lightning can start nuclear reactions in the sky

Lightning. Photo: 4FR / iStock

Lightning can create fusion reactions in the air around it, according to research published today in the journal Nature. Nuclear reactions were thought to occur in some thunderstorms but the study provides the first conclusive evidence they are happening.

Why it matters: It's unclear how thunderstorms and lightning work. "How lightning initiates inside thunderstorms is a complete mystery, and how lightning initially moves inside the storms is not at all clear," lightning expert Joseph Dwyer from the University of New Hampshire tells Axios in an email. He says figuring out how some thunderstorms emit huge gamma-ray flashes thought to trigger the reactions "might tell us something interesting about what's going on inside the storms."

The question: It seems theoretically impossible for lightning to produce nuclear fusion reactions because the fuel for the reactions — a form of hydrogen called deuterium — isn't available in large enough amounts in the atmosphere. The 50,000°F temperature of lightning is also a lot cooler than the 30,000,000°F near the center of the Sun where nuclear fusion occurs. Yet scientists have observed by-products of these reactions being produced from lightning.

How it works: Lightning can emit high-energy bursts known as gamma-ray flashes. (How and when they occur — they are associated with a small fraction of lightning seen around the world each day — is a mystery itself.) The flashes are energetic enough to knock neutrons out of the nuclei of nitrogen and oxygen in the air, creating radioactive versions of them for a short time.

Researchers have seen signatures of neutrons being formed just after a lightning flash before. The new paper reports a second such observation on February 6, 2017 Japan along with detection of the radioactive nitrogen and oxygen produced when neutrons are removed from their nuclei.

"It leaves no possible doubt as to what's going on, and it's a beautiful and thorough analysis," says David Smith, a physicist at the University of California Santa Cruz who studies gamma-rays produced by lightning and wasn't involved in the research.

What's next: The gamma-ray flashes themselves were too bright for the researchers' instruments to record. Dwyer says having better instrumentation in places where there are lots of thunderstorms and on aircraft flying near storms would be a very important next step to confirm the bursts start the reactions.

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Vaccine researcher dodged medical regulations, conducted trials in hotels

Photo: AlexKich / iStock

Unlicensed and unregulated experimental vaccines were administered to at least eight herpes patients in the United States, in direct violation of US law, according to an investigation by Marisa Taylor at Kaiser Health News. The experiments were conducted secretly for several years in a Holiday Inn Express and Crown Plaza Hotel near Carbondale, Illinois.

What we already knew: William Halford, the associate professor at Southern Illinois University who conducted the experiments, died of cancer this summer. Halford had previously been accused of dodging US oversight laws by running trials out of a house on the island of St. Kitts in 2016. The St. Kitts and Nevis government says they were not notified of the research.

Why it matters: "We're not allowed to do this in guinea pigs in this country let alone human subjects," herpes expert Anne Wald told Kaiser Health News.

Money: Despite the controversy, a number of investors, including Peter Thiel, have invested several million dollars in Rational Vaccines, the company founded by Halford and Hollywood filmmaker Agustín Fernández III.

Deception: Halford, who was not a physician, took clear steps to cover his tracks, telling participants to keep the experiment a secret and "writing that it would be 'suicide' if he became to public about how he was conducting his research," writes Taylor.

Complications: Patients have reported side effects from the vaccine. Kaiser Health News reports that one participants fear that the vaccine gave him a new, different type of herpes is "possible."

Contamination: Not only were the trials conducted in violation of US law, they were conducted using live viruses. Live virus vaccines are traditionally handled in extremely sterile areas - which Holiday Inns are not - to prevent contamination.

Manipulation: Halford used patient's desire for a cure to manipulate them into joining the unauthorized trial: "People underestimate how desperate people with genital HSV are," Wald told Kaiser Health News.

Denial: Southern Illinois University, which previously denied it had any knowledge of Halford's action, refused to comment to Taylor.

Read the full Kaiser Health News report here.


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Why lefties have a competitive edge in certain sports

Pro-tennis player Martina Navratilova is left-handed. Photo: Jeff Daly / Invision via AP

A new study that analyzed whether left-handed people have a competitive advantage in sports over right-handed people found the distinction is more pronounced for sports in which a player has less time to react to an opponent, per the New York Times.

The score: Most players are trained to strategize based on righties' weaknesses (throwing a ball to their opponent's less dominant side, the left) which in turn may be an advantage for lefties because their opponents have a harder time anticipating their next move.

Details from the study:

  • Loffing studied six different sports: baseball, cricket, table tennis, badminton, tennis and squash — all of which incorporate a "standardized measure of time pressure," as Loffing described it.
  • Findings: Comparing all six sports, he found left-handed dominance was 2.6 times more likely in sports with higher time constraints like baseball, cricket and table tennis, than in those with lower time pressure (badminton, tennis and squash). "Nine percent of the top players were left-dominant in the slowest contest, squash, while 30 percent of the best pitchers were lefties in the fastest, baseball," reports NYT.
  • Loffing's bottom line: "We know that things like anticipation and decision-making are more difficult under time pressure," he said.
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Albatross are in decline, mirroring drops in shorebirds around the world

Wandering albatross nest on Prion Island in South Georgia. Photo iStock / Burroblando

Populations of wandering albatross are half as large as they were in the 1980s, according to a paper published Monday in the journal Proceedings of the National Academy of Sciences.

What's happening: According to the BBC, there are two main reasons for the bird's decline:

  • Fishing: The birds "often try to take the bait on longline fishing gear. They get snagged on hooks, are pulled under the water and are drowned."
  • The climate: The birds are vulnerable to shifts in feeding grounds caused by events like El Nino and climate change.

Why it matters: It's not just wandering albatross. A study published last year in Nature found seabird populations are crashing around the globe, and another published in PLOS One in 2015 found that seabird numbers have dropped 70 percent in 60 years.

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6-month-old infants may understand related words

Thomas Brunson-Pitts, 6 months, plays inside his home in Washington. Photo: Jacquelyn Martin / AP

New research suggests babies as young as six months old understand more about language than was previously believed, per the Atlantic.

In the study, babies were first shown two different pictures at a time, of things like a blanket and a dog. Researchers observed what image the babies looked at after their parents named an image. The babies had a harder time distinguishing the difference between pictures of related things, like nose and mouth, than they did of the unrelated pictures. Per the Atlantic, this difficulty of distinguishing related images shows "that they somehow understand that the concepts are related."

Why it matters: Further developing the findings could help doctors flag when a child has a language delay, which is sometimes an indicator of autism.

A different part of the study included the parents showing an object to the baby while they discussed it. Following this, the babies were able to "look more at the correct objects during the in-lab task," the Atlantic reports. Elika Bergelson, lead author of the study, said this shows that "babies are listening, and you should treat them as conversational partners."

What's next: Bergelson acknowledged that more work needs to be done, considering this study only used 51 children, and they were primarily from "white, middle-class, well-educated families."

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Ancient fortress found at bottom of lake in Turkey

The Akdamar church stands on the Akdamar Island on Lake Van, Turkey. Photo: Burhan Ozbilici / AP

Archaeologists have discovered the ruins of an ancient fortress believed to be about 3,000 years old at the bottom of Lake Van, located in eastern Turkey near Iran, per National Geographic.

How it remained hidden: Lake Van isn't connected to the ocean so it is highly susceptible to dramatic changes in water levels. Archaeologists believe the lake's water level was lower when the Uratu kingdom reigned from 860-590 BC. Locally, people talked about ruins from the Uratu kingdom at the bottom of the lake.

One fun thing: Tahsin Ceylan, the head of the diving team from Van Yuzuncu Yil University who led the expedition, told local press that most archaeologists and museum officials told them not to search the lake because they'd never find anything. The diving team proceeded with their search anyway, based on the local rumors. They then discovered the fortress.

Details of the ruins: Ceylan said the archaeological site is about a kilometer long, and roughly 10 to 13 feet of castle walls are visible beneath the water.

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Elon Musk's new truck said to have a revolutionary new battery

Musk with the Tesla semi truck. Photo: Tesla

When Elon Musk guaranteed that the new Tesla semi-truck would last 1 million miles without breaking down, experts assumed he was talking about the drive train, not the ultra-sensitive battery. But a person familiar with the truck tells Axios that he meant the battery, too.

Why it matters: A battery going that far would have multiple times the longevity of any commercial vehicle battery in use now or announced for release, and would help make Tesla's Semi competitive with diesel-burning competitors (since the battery is estimated to cost $170,000 on top of the $100,000-plus cost of the truck itself).

Musk announced his truck with typical showmanship (see photo above), but fleet owners who buy cargo trucks are not typically given to whims of cool and style. "They decide on the total cost of ownership," John Rapaport, a co-founder of Repower, a consultant to truck fleet owners, tells Axios. "They are very sophisticated buyers. They understand how to model out all of the variables."

By the numbers: In his Nov. 16 unveiling of the Semi, Musk said the truck will travel 500 miles on a charge when it goes on sale starting in 2019, which is a lot; Mitsubishi's new eCanter has 62.5 miles of range on a charge. Given that the standard lithium-ion battery lasts 1,000 charge-discharge cycles before replacement is recommended, that would add up to about 500,000 miles.

  • But a typical tractor-trailer in the U.S. will travel 100,000 miles a year or more, according to industry data. Meaning that, if Musk's truck operates like most electrics including Tesla's own passenger vehicles, it would deliver only about five years of use before the battery needs replacing.
  • Truck drivers are also likely to use Tesla's 30-minute fast-charging technology almost every time their battery runs out, and not the slower recharging system, thus subjecting the pack's physics to regular, enormous stress, said Venkat Viswanathan, a professor at Carnegie Mellon University.
  • Musk has not disclosed his planned sticker price, but experts estimate that the Semi could be $300,000, about twice the cost of new diesel trucks. Very few fleet owners would spend that kind of money if the battery needs replacing so soon, even if they do save about $100,000 in diesel over the five years of ownership, as Tesla estimates.

That Musk instead plans to guarantee 1 million miles of travel, as we have been told, suggests his team has tinkered with the truck in unprecedented ways so that the battery can undergo 2,000 charge-recharge cycles, twice the usual number, Viswanathan said.

In a series of tweets, Nikola Motor Company, a rival truckmaker, yesterday speculated that Musk is modeling his battery pack not on his passenger vehicles, but on his stationary batteries — the Powerwall that he markets for use in buildings and homes. Such a configuration — installing many more battery cells than actually required, and running them at relatively low charging voltage — would make the system much more durable, Viswanathan said.

In an email exchange, Tony Seba, who teaches at Stanford University, adds that self-driving technology will make the Semi more efficient, and suggests that drivers may not be permitted to fully discharge the batteries. "If you don't fully charge and discharge a battery, it's going to last far longer than if you do," Seba said.

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There might not be flowing water on Mars

Mars' recurrent slope linnea, or RSL, may have been caused by flowing sand and not water.

Photo: NASA / JPL-Caltech / UA / USGS

Hopes of flowing water on Mars are evaporating. In 2015, scientists announced they had found dark streaks on mountains on Mars. At the time, they believed the streaks were formed by running water. However, a paper published Thursday in Nature Geosciences suggests the streaks were instead shaped by falling sand.

Why it matters: It seems counterintuitive, but this could make plans to travel to Mars a little easier. If there's running, liquid water on Mars, there could also be life. And that means that any missions would have to go to great lengths to avoid contaminating it. The authors note any water that is present would likely be "inhospitable to known terrestrial life, alleviating planetary protection concerns."

  • That doesn't mean there isn't life on Mars, but it's even less likely than before — and it probably won't be contaminated by any bacterial hitchhikers humans might send along.

What they saw: The researchers compared the patterns left by flowing sand on Martian sand dunes to the dark streaks, which are called recurring slope linnea, or RSL. The patterns on the dunes were startlingly similar to the patterns on the RSL. And, although the streaks do look like they contain some salts associated with liquid water, other salts can't be seen. Previous studies had suggested that if there was water in the streaks, there was little of it.

Yes, but the streaks do seem to lengthen during the warm season, suggesting liquid water under the surface could play a role in starting the sand on its journey downhill.

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First asteroid seen from outside our solar system has bizarre shape

An artist's illustration of the first interstellar asteroid, `Oumuamua. Credit: European Southern Observatory.

Astronomers today confirmed that an asteroid first spotted zipping through our solar system last month came from another star system. 'Oumuamua — Hawaiian for "a messenger from afar arriving first" — is one of the most elongated cosmic objects known to date.

Why it matters: 'Oumuamua's bizarre shape is unlike any other asteroid seen yet, and could "provide new clues regarding into how other solar systems formed," according to a NASA press release.

'Oumuamua's distinguishing characteristics, detailed by a team of astronomers led by Karen Meech from the Institute for Astronomy in Hawaii, and published Monday in the journal Nature:

  • 'Oumuamua's orbit isn't possible in our solar system, the researchers concluded, meaning it came from another solar system.
  • The cigar-shaped asteroid is dark and reddish, and is about ten times long as it is wide.
  • Unlike comets, it doesn't have any gas or dust surrounding it. But it is similar to some comets and asteroids. "This is important because it suggests that planetary compositions like ours could be typical across the Galaxy," Stuart Clark writes in the Guardian.
  • According to NASA, these properties "suggest that 'Oumuamua is dense, comprised of rock and possibly metals, has no water or ice, and that its surface was reddened due to the effects of irradiation from cosmic rays over hundreds of millions of years."

Timeline:

  • The object was first discovered Oct. 19 by the University of Hawaii's Pan-STARRS1 telescope. Soon after, telescopes around the globe, including the European Southern Observatory's s Very Large Telescope in Chile, began measuring the asteroid's characteristics.
  • The asteroid can still be seen by large ground-based telescopes, but it is rapidly fading from view as it travels away from Earth. It is expected to no longer be detectable around mid-December.
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Why experts are quietly concerned about bird flu

Chickens on a farm chicken on the outskirts of Shanghai, China, on April 3, 2013. Photo: Gillian Wong / AP

Global health officials are quietly ratcheting up concern about H7N9 bird flu, per the New York Times. "The number of human infections reported in [this epidemic] is almost as many as were reported during the previous four epidemics combined," notes the CDC of this years' flu season, though they believe this is due to increased spread among birds, not improved human transmission.

The bottom line: This particular lineage of H7N9 has long been "ranked as the influenza virus with the highest potential pandemic risk," according to the CDC. But there isn't yet a pandemic, and there might never be one. H7N9 could continue to be a small, regional problem like another influenza virus known as H5N1 has, or it could spread (comparatively) harmlessly, like H1N1/swine flu. Regardless, those who study the disease are watching it closely.

The CDC summarized recent developments in a September update of the Morbidity and Mortality Weekly Report, and in October the World Health Organization noted a seasonal uptick in cases.

Since October 2016:
  • 1600 people have tested positive for the virus.
  • 40% of those who tested positive have died.
  • The virus has become fatal in birds, which means it's potentially more deadly in humans.
  • The virus has split into two strains, which could interfere with vaccine development.
  • Research has shown it can transmit easily in ferrets. Viruses that succeed in ferrets are often successful in humans.

Reality check: Most of the infected humans caught the virus directly from birds. But it's not clear where a small number of people contracted the illness, raising concerns about human-to-human transmission. It's worth noting that bird flu strain H5N1, which first appeared in 2005, still can't successfully pass from person to person, so public health officials are slow to raise alarm.

Also worth watching: Australia just had one of their worst flu seasons on record, and the strains that circulated there are slated to be prevalent in the U.S. this flu season. But the U.S. has much higher vaccination rates than Australia, so the season may not be as bad, notes the NYT's Donald G. McNeil, Jr.