Astrophile: A scorched world with snow black and smoky

Astrophile is our weekly column on curious cosmic objects, from the solar system to the far reaches of the multiverse

Object: Titanium oxide snow
Location: The hot-Jupiter planet HD 209458b

There is something magical about waking up to discover it has snowed during the night. But there's no powdery white blanket when it snows on exoplanet HD 209458b. Snow there is black, smoky and hot as hell – resembling a forest fire more than a winter wonderland. Put it this way: you won't be needing mittens.

HD 209458b belongs to a family called hot Jupiters, gas-giant planets that are constantly being roasted due to their closeness to their sun. By contrast, the gas giants in our immediate neighbourhood, including Jupiter, are frigid, lying at the solar system's far reaches.

HD 209458b is also noteworthy because it is tidally locked, so one side is permanently facing towards its star while the other is in perpetual night. On the face of it, these conditions wouldn't seem to invite snow: temperatures on the day side come close to 2000° C, while the night side is comparatively chilly at around 500° C.

Snow made of water is, of course, impossible on this scorched world, but the drastic temperature differential sets up atmospheric currents that swirl material from the day side to night and vice versa. That means that any substances with the right combination of properties might be gaseous on the day side and then condense into a solid on the night side, and fall as precipitation. Say hello to titanium oxide snow.

Stuck on the surface

Although oxides of titanium make up only a small component of a hot Jupiter's atmosphere, these compounds have the right properties to fall as snow. But there was a snag that could have put a stop to any blizzards. Older computer models of hot Jupiters suggested that titanium oxides condensing in the air on the night side would snow – and remain on the relatively cool surface forever. "Imagine on Earth if you had no mechanism to evaporate water, it would never rain," says Vivien Parmentier of the Côte d'Azur Observatory in Nice, France.

Now he and colleagues have created a more detailed 3D computer model that shows that the snow can become a gas again as it falls and the temperature and pressure increase. Strong updraughts can then blow the titanium oxides back to the upper atmosphere. "The gas can come back on the top layers and snow again and again," says Parmentier.

Snowfall on HD 209458b would be like none you've ever seen. Though titanium dioxide is white and shiny, for example, the snowflakes would also contain silica oxides from the atmosphere, making them black. Since the atmosphere is also dark, snowstorms on the planet would be a smoky affair, the opposite of the white-outs we get on Earth. "It would be like being in the middle of a forest fire," says Parmentier.

Although the team studied a particular hot Jupiter, their model should apply equally to other planets of this type, suggesting hot snow is a common occurrence. Parmentier says we may have already spotted snow clouds on another hot Jupiter, HD 189733b, as spectral analysis of the planet suggests the presence of microscopic particles in its atmosphere.

David Sing of the University of Exeter, UK, who helped identify such particles on HD 189733b, says the team's new model goes a long way to explaining how titanium oxides behave on hot Jupiters. "We're pretty used to water condensing on Earth; there it is titanium because the temperatures are so much hotter."

Hot, black snow – now that would be something to wake up to.

Reference: http://arxiv.org/abs/1301.4522

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Cambodians bid farewell to ex-king ahead of cremation

PHNOM PENH: Thousands of Cambodians paid their last respects to their beloved former king Norodom Sihanouk as his body lay in state Saturday ahead of his cremation next week.

The mourners were able to glimpse the late monarch's gilded casket through doorways to the purpose-built crematorium where it was carried Friday in a lavish procession that brought Phnom Penh to a standstill.

His body will be kept at the crematorium until Monday when his wife and his son, current King Norodom Sihamoni, will start the cremation ceremony.

"I had the chance to pay my last respects to the King-Father," 65-year-old Sun Sopho, told AFP, with tears in her eyes, reflecting the sorrow of many who see Sihanouk as a force of stability over six turbulent decades.

"I asked his soul to bless us and to keep peace for the country forever."

The mercurial ex-monarch died of a heart attack aged 89 in Beijing on October 15 last year.

Sihanouk was just 18 when placed on the throne in 1941 by French colonial authorities, but quickly defied his patron's expectations of a pliant king.

A father of 14 children over six marriages, Sihanouk abdicated in 2004 after steering Cambodia through six decades marked by independence from France, civil war, the murderous Khmer Rouge regime, his own exile and finally peace.

Sihanouk -- a self-confessed "naughty boy" who loved to direct films, write poetry and compose songs -- remained hugely popular among Cambodians. But his record is not without controversy.

After being ousted by the US-backed General Lon Nol in 1970, he aligned himself with the Khmer Rouge, only to be placed under house arrest as the communist regime terrorised the nation.

Before the Vietnamese toppled the Khmer Rouge in 1979, Sihanouk took exile in China. He regained his throne in 1993, although his influence was greatly diminished and he abdicated in 2004 to be succeeded by Sihamoni.

-AFP/ac

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Powertrekk fuel cell charger to be released in Spring

Along with a fuel cell puck, the PowerTrekk gives your iPhone a bit of juice. Just add water.

(Credit:
Lynn La/CNET)

While it's been circulating around at trade shows for a while, including Mobile World Congress 2011 and CES 2012, the PowerTrekk phone charger is slated to finally come to the U.S. at the end of this quarter.

Although the $229 device is peddled as a charger that can simply juice up your phone on water alone, it's not quite that simple.

To use the PowerTrekk, you also have to purchase a $4 PowerTrekk Pukk. Once you add a small amount of water (about half a shot), and add a one-time-use Pukk, the latter will immediately begin separating the hydrogen from the water, using it as fuel to charge your handset.

Each Pukk will produces 2.5 watts at 5 volts, which is good for about one full iPhone charge. If there is electricity available, however, you can also charge the separate internal battery in the PowerTrekk so it can power your phone later on.

Power your phone in an emergency

When I handled the unit at iWorld in San Francisco, it was indeed very lightweight despite its industrial look, and in a situation where there is no sun, I can see it coming in handy.

However, there is much debate about how useful a product like this can be. Not only is it rather cumbersome in shape, but you'll need to continually buy more Pukks in order to use the device multiple times. Compared to solar chargers and chargers that run on kinetic energy, this can become wasteful and pricey.

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Pictures We Love: Best of January

Photograph by Dieu Nalio Chery, AP

The magnitude 7 earthquake that struck near Port au Prince, Haiti, in January 2010 so devastated the country that recovery efforts are still ongoing.

Professional dancer Georges Exantus, one of the many casualties of that day, was trapped in his flattened apartment for three days, according to news reports. After friends dug him out, doctors amputated his right leg below the knee. With the help of a prosthetic leg, Exantus is able to dance again. (Read about his comeback.)

Why We Love It

"This is an intimate photo, taken in the subject's most personal space as he lies asleep and vulnerable, perhaps unaware of the photographer. The dancer's prosthetic leg lies in the foreground as an unavoidable reminder of the hardships he faced in the 2010 earthquake. This image makes me want to hear more of Georges' story."—Ben Fitch, associate photo editor

"This image uses aesthetics and the beauty of suggestion to tell a story. We are not given all the details in the image, but it is enough to make us question and wonder."—Janna Dotschkal, associate photo editor

Published February 1, 2013

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Gov's Handling of Sandusky Case Under Investigation

The newly-elected attorney general of Pennsylvania is going after the state's governor, Tom Corbett, who was attorney general when child sex allegations against Penn State coach Jerry Sandusky were first brought forward.

Kathleen Kane, a Democrat who was sworn in as attorney general on Jan. 15, said that she will name a special prosecutor in the coming days to investigate Corbett's handling of the Sandusky case. Corbett is a Republican.

The investigation will look specifically at why it took the attorney general's office three years to bring criminal charges against Sandusky while he continued to have access to children.

"Attorney General Kane will appoint a special prosecutor to lead the office's internal investigation into how the Sandusky child abuse investigation was handled by the Office of the Attorney General," Kane's office said in a statement released today.

Corbett's attorney general's office was first notified of the allegations against Sandusky in 2008 when a high school student told his mother and school that Sandusky had molested him. The local district attorney passed the allegation on to the attorney general, then Corbett. Corbett convened a grand jury.

Mario Tama; Patrick Smith/Getty Images

Jerry Sandusky Insists Innocence Before Sentencing Watch Video

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Jerry Sandusky Claims Innocence in Audio Statement Watch Video

It wasn't until 2011 that sex abuse charges were filed against Sandusky while Corbett had since become governor. Sandusky was convicted on 45 counts of sex abuse in June 2012.

The charges sent shockwaves throughout Pennsylvania, as Penn State's president, two top officials, and legendary coach Joe Paterno all lost their jobs over the scandal.

"Why did it take 33 months to get Sandusky off the streets? Was the use of a grand jury the right decision? Why were there so few resources dedicated to the investigation? Were the best practices implemented?" the statement from Kane's office read.

"At the end of this investigation, we will know the answers to these questions and be able to tell the people of Pennsylvania the facts and give them answers that they deserve," the statement said.

Describing an interview Kane gave the New York Times, the Times said Kane suggested that Corbett did not want to upset voters or donors in the Penn State community before his gubernatorial run in 2009.

Corbett has denied those suggestions. His office did not immediately return calls for comment.

Kane's office preemptively fought back against the idea that the investigation is politically motivated. Kane, a Democrat, defeated the incumbent attorney general, Linda Kelly, a Republican in November 2011. Corbett is a Republican.

"The speculation that this is about politics is insane," a staff member in Kane's office told ABC News today. "You go anywhere in Pennsylvania and anywhere across the country and you'll find individuals asking, 'why did it take three years? Why was there a grand jury? Why make these kids talk to 30 different people about what happened?"

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Swarm-mongering: Brainless blobs flock together

Birds of a feather flock together and now so do brainless, inanimate blobs. Made of microscopic particles, the artificial swarms could shed light on the mysterious mechanisms behind the natural swarming seen in fish and birds. They might also lead to materials with novel properties like self-healing.

Animals such as birds, fish and even humans that move together in swarms have individual intelligence, but Jérémie Palacci of New York University and colleagues wondered whether inanimate objects could also swarm. "From a physicist's point of view, if many different systems behave in the same way there must be an underlying physical rule," he says.

To explore this idea, the team created microscopic plastic spheres, each one with a cubic patch of haematite, an iron oxide, on its surface. When submerged in hydrogen peroxide, the spheres spread out in a disordered fashion. The team then shone blue light on the particles, causing the haematite cubes to catalyse the breakdown of any nearby hydrogen peroxide into water and oxygen. As hydrogen peroxide concentration dropped temporarily in these regions due to the reaction, osmotic forces cause more hydrogen peroxide to flow into them, and that in turn buffets the spheres. The whole process then repeats.

Self-healing swarm

When two spheres come close enough to each other, the balance of chemical forces shifts so that the two spheres are attracted. If there are enough spheres in the same place they will cluster together to form shapes of symmetrically arranged particles, which the team call crystals (see video, above). These crystals continue to be buffeted by the movement caused by the breakdown of hydrogen peroxide – but now they move together as one object, replicating a life-like swarm. Switch off the light, however, and the reaction stops, causing the crystal to lose the forces that hold it together, and the particle distribution becomes disordered once again.

"This system shows that even though the particles have no social interaction or intelligence, you can exhibit collective behaviour with no biology involved," says Palacci. Since the haematite is magnetic, it is even possible to steer the crystals in one direction by applying a magnetic field. Such control might be useful if the artificial swarms are to be harnessed for applications.

As the particles automatically fill any gaps that form in the crystal, again thanks to the chemical dynamics of the system, they could be used to create a self-assembling, self-healing material. The work is published in the journal Science today.

Schooled by fish

Iain Couzin of Princeton University says these kinds of systems are very useful for studying biological collective behaviour because researchers have complete control over their interactions – unlike natural systems.

His team has its own swarming experiment published in the same issue of Science, based on schools of fish that prefer to stay in shade. Their paper shows that shining a light on some of the fish in the school causes them to speed up, to get away from the light. But as a result, non-illuminated fish also speed up, even though, if acting purely as individuals, they would have had no reason to do so. "We show just by using simple interactions that schools can have a sense of responsiveness to the environment that individuals do not have," he says.

Couzin sees no reason why such behaviour should be limited to natural systems. "In future it may be possible to create systems of particles that can make collective decisions – something we often think of as only possible in biological systems," he says.

Journal references: Living crystals: Science, DOI: 10.1126/science.1230020; Fish: Science, DOI: 10.1126/science.1225883

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

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"The sooner, the better" for COC on South China Sea: Shanmugam

SINGAPORE: Foreign Affairs Minister K Shanmugam has reiterated the need for a Code of Conduct (COC) on the South China Sea, saying the sooner it is started the better.

He said this in a live interview with the BBC on Friday morning, covering issues such as the South China Sea claims, US-China relations and ASEAN.

He was asked whether it is possible to have some kind of resolution via ASEAN.

Mr Shanmugam replied that ASEAN has been trying to make it clear that territorial disputes can only be solved by the claimant states themselves.

But the regional grouping can put in place a structure that shows and tells people how they have to structure their conduct with each other. And this is why ASEAN has been pushing for the COC.

Mr Shanmugam said the COC should apply to all countries in the way they interact with each other in the region.

Asked how concerned Asia should be over what's perceived as an increasingly assertive China, Mr Shanmugam said this has to be looked at in context.

He said no leader of China, as well as leaders of many countries, can afford to be seen to be soft on sovereignty.

The real issue is whether they can put in place a modus vivendi to deal with territorial and sovereignty issues.

Mr Shanmugam pointed out that the actual disputes will take a very long time to settle and stressed that the issue is how countries behave so that the disputes do not escalate into clashes, which could be terrible for the region.

- CNA/ir

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DotCom's Mega removing legitimate files

Thousands of legitimate files are being blocked and removed from users' Mega accounts, even when the file is legal for sharing, according to a report.

TorrentFreak tested the situation, uploading a number of files free for sharing, including, amusingly, a video explaining fair use and a copy of Mega founder Kim DotCom's own music single. All were removed within minutes, with TorrentFreak receiving e-mails from Mega explaining that a take-down notice had been issued on the files.

The problem is that Kim DotCom recently took to Twitter to claim that Mega was receiving only 50 copyright take-down notices a day, which doesn't explain the number of files being removed.

Read more of "Kim Dotcom's Mega removing legitimate files" at CNET Australia.

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Sinkhole Swallows Buildings in China

Photograph from AFP/Getty Images

The sinkhole that formed in the southern Chinese city of Guangzhou (pictured) is, unfortunately, not a new occurrence for the country.

Many areas of the world are susceptible to these sudden formations, including the U.S. Florida is especially prone, but Guatemala, Mexico, and the area surrounding the Dead Sea in the Middle East are also known for their impressive sinkholes. (See pictures of a sinkhole in Beijing that swallowed a truck.)

Published January 31, 2013

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Arias' Lawyer Shows Ex-Boyfriend's Lewd Photos

Accused murderer Jodi Arias was kept away from the Mormon friends of her lover Travis Alexander and their torrid sex affair was kept secret by Alexander, even as he sent lewd photos of himself to her online, according to court testimony today.

The testimony in Arias' trial for killing Alexander in 2008 was intended to bolster the defense's argument that she killed him in self defense, that Alexander was a sexual deviant who treated Arias as his "dirty little secret."

Arias' attorneys introduced as evidence photos that Alexander took of his penis and sent to Arias, part of a string of graphic messages and sexual phone calls the two engaged in while Alexander, an elder in the Mormon church, was supposed to be chaste.

Today's witness was the latest in a string called by the defense, including Alexander's former girlfriend Lisa Daidone, who told the court that Alexander had professed to be a virgin.

Daniel Freeman continued his testimony today, describing how he was a friend of both Arias and Alexander but that Alexander kept Arias distanced from his Mormon pals.

"Travis had made more friends at (the Mormon) ward, and had (Ultimate Fighting Championship) fight nights at his house many times, and Jodi was in town, but she wasn't there," Freeman said.

"There was that group of friends, them and Jodi, two different groups, and so Lisa [Daidone] and friends from church were there, but Jodi wasn't there," Freeman said.

Jodi Arias Murder Trial: Former Boyfriend Takes Stand Watch Video

Jodi Arias Murder Trial: Defense's First Day of Witnesses Watch Video

Alexander's behavior, the defense hopes to prove, shows that he mistreated Arias.

Arias, 32, is on trial for murdering Alexander, whom she dated for a year and continued to have a sexual relationship for a year after that. Her attorneys claim that Alexander was abusive and controlling toward Arias, and that she was forced to kill him.

Freeman described how he took a trip with his sister, Alexander, and Arias, and how Alexander had asked him to come along so that he and Arias "would not get physical."

"I don't know that I can say he didn't want to be alone with her, but he liked that when I was there, and my sister was there. They weren't as physical," Freeman said.

Freeman admitted that he had no idea Alexander and Arias had been having a sexual relationship the entire time they were together. He said Alexander never mentioned that to his friends.

In fact, Freeman noted that Alexander was considered to be a church elder when he baptized Arias into the Church of Latter-Day Saints. Both a church elder and a convert were expected to abide by the church's strict law of chastity, which banned any sexual relations outside of marriage.

"One thing people give up in this baptism process was sex," prosecutor Juan Martinez said. "Did you know she was having oral sex with Mr. Alexander at the time of her baptism? Would that be an insincere baptism?"

"She would not be ready to be baptized in that case," Freeman said.

"You were asked about Miss Arias, whether she was worthy of baptism if she was performing oral sex, but what about the elder receiving oral sex?" defense attorney Kirk Nurmi said.

"They would not be worthy of performing that ordinance at that time until they had gone through repentance," Freeman said. "They would go to a discipline council and could face excommunication or a probation period or have their priesthood removed."

Freeman said that Alexander never confessed to having a sexual relationship with Arias.

Freeman's testimony came on the third day of the defense's attempt to paint Alexander as a controlling, sex-obsessed liar who was cruel to Arias. Other witnesses have said that Alexander cheated on other women he dated with Arias, and lied to his friends and family about their relationship.

The defense also had Freeman point out that Alexander was strong and fit. They are expected to conclude that Alexander was physically threatening Arias when she killed him.

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