Science & TechnologyS


Info

Ancient Egyptians knew Algol was a variable star

Sergio Prostak
Sci-News
Wed, 23 Dec 2015 21:55 UTC
Egyptian Papyrus
© Jetsu L. / Porceddu S., doi: 10.1371/journal.pone.0144140.s001Text of Cairo Calendar page rto VIII; inside the superimposed rectangle is the hieratic writing for the word Horus. A passage in this document dates it to the reign of Ramses II in the Nineteenth Dynasty.
Ancient Egyptians wrote Calendars of Lucky and Unlucky Days that assigned astronomically influenced prognoses for each day of the year. The best preserved of these calendars is the Cairo Calendar dated to 1244 - 1163 BC (Ramesside Period). According to scientists at the University of Helsinki, this papyrus is the oldest preserved historical document of naked eye observations of a variable star, the eclipsing binary star Algol.

The Egyptian Museum of Cairo purchased this unique hieratic papyrus from an antiquities dealer in 1943. Twenty three years later, Egyptian scientist Abd el-Mohsen Bakir published it as the Cairo Calendar No. 86637.

The document is divided into three sections (Books I, II and III). Its largest part, Book II, consists of 365 passages, one for each day of the 360-day Egyptian year plus five epagomenal days. The passages seem to concern religious feasts, mythological incidents, favorable or adverse days, forecasts, and warnings.

University of Helsinki researchers Lauri Jetsu and Sebastian Porceddu have now performed a statistical analysis of the texts of this document.

"Our statistical analysis leads us to argue that the mythological texts of the Cairo Calendar contain astrophysical information about Algol," the scientists said.

The analysis revealed that the periods of the variable star Algol (2.85 days) and the Moon (29.6 days) strongly regulate the actions of deities in this calendar.
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Question

Do dogs recognize other dogs as dogs?

Julie Hecht
Scientific America
Tue, 29 Dec 2015 16:52 UTC
dogs
Pug meets Afghan
Do you see dogs everywhere?

My ears perk up to the jingle jangle of metal-on-metal, hopeful that it predicts a dog and his collar, disappointed when it turns out to be keys on a belt (boring).

A person walking down the street with their arm outstretched holds the promise of a leash with a dog on the other end (sometimes it's a stroller holding a kid. Oh well).

From a distance, my eyes play a cruel trick on me, where shopping bags are dogs and dogs are shopping bags until I get close enough and one wins out (obviously I'm rooting for the dog).
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Robot

Humanity's planned obsolescence? The robot revolution got real in 2015

Lauren O'Neil
CBC
Tue, 29 Dec 2015 12:02 UTC
Robots to serve or replace?
© Unknown
Evidence of humans fearing technology dates back to the Industrial Revolution, when what came to be known as "technophobia" was first observed.

As it turns out, some of those fears were justified.

Violent man-versus-machine conflicts saw members of the British working class destroying the devices that had replaced their jobs well into the 1800s, setting the stage for centuries of anti-robot rhetoric played out in books, movies and ideological movements

Today, serious fears of a "robot revolution" are only just starting to crystallize for the average person - but it's happening quickly, and spreading far beyond the confines of science fiction.
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Mars

Boulders on a Martian landslide


Phys.org
Tue, 29 Dec 2015 00:00 UTC
Mars land
© NASA/JPL/University of Arizona
The striking feature in this image, acquired by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter on March 19, 2014, is a boulder-covered landslide along a canyon wall. Landslides occur when steep slopes fail, sending a mass of soil and rock to flow downhill, leaving behind a scarp at the top of the slope. The mass of material comes to rest when it reaches shallower slopes, forming a lobe of material that ends in a well-defined edge called a toe.

This landslide is relatively fresh, as many individual boulders still stand out above the main deposit. Additionally, while several small impact craters are visible in the landslide lobe, they are smaller in size and fewer in number than those on the surrounding valley floor. The scarp itself also looks fresh compared to the rest of the cliff: it, too, has boulders, and more varied topography than the adjacent dusty terrain.

Just to the north of the landslide scarp is a similarly-shaped scar on the cliffside. However, there is no landslide material on the valley floor below it. The older landslide deposit has either been removed or buried, a further indicator of the relative youth of the bouldery landslide.
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Magnify

Success in observing a two-phonon quantum interference: A world first


ScienceDaily
Mon, 28 Dec 2015 00:00 UTC
ion trap
© Osaka UniversityThis is a photograph of ion trap and 2 ions (top right).
Key to further study on quantum information processing

A research group at Osaka University has succeeded in observing at the intended timing two-phonon quantum interference by using two cold calcium ions in ion traps, which spatially confine charged particles.

A phonon is a unit of vibrational energy that arises from oscillating particles within crystals. Two-particle quantum interference experiments using two photons or atoms have been previously reported, but this group's achievement is the world's first observation using two phonons.

This group demonstrated that the phonon, a quantum mechanical description of an elementary vibrational motion in matter, and the photon, an elementary particle of light, share common properties. This group's research results will contribute to quantum information processing research, including quantum simulation using phonons and quantum interface research.
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Magnify

Bionic eye might help restore vision


New Scientist
Tue, 15 Dec 2015 00:00 UTC
eye closeup
In future you may not even need eyes to see. Next year, a blind person in Australia will be the first to receive "bionic eyes" that bypass most of the visual system entirely. Instead, a camera mounted on a pair of glasses will feed information about the world directly to the brain.

The breakthrough should help restore vision in people without a working retina. "You don't need an eyeball at all," says Arthur Lowery at Monash University in Clayton, Victoria, who is developing the bionic eye.

The plan is to implant up to 11 small tiles, each loaded with 43 electrodes, into areas of the brain that deal with vision. When these areas are stimulated, people report seeing flashes of light. Lowery believes that each electrode could create a dot of light that is similar to seeing one pixel. In total, the tiles will provide around 500 pixels - enough to create a simple image. Although this resolution is far cruder than the 1 to 2 million pixel image a normal eye can produce, it should restore the basic elements of sight.

Comment: Also see:
  • Hope of restored vision with bionic eye [link]
  • Dragonflys and artificial sight [link]
  • Seeing again after 33 years [link]


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Info

Meteor dust sucking up electrons in atmosphere

Tia Ghose
Live Science
Tue, 29 Dec 2015 14:19 UTC
Earth's atmosphere
© NASA/GoddardThe layers of Earth's atmosphere. A mysterious decline in the concentration of free electrons occurs in the D-region of the ionosphere, a phenomenon known as the D-region ledge. Now, researchers suggest the ledge can be explained by the burn up of tiny meteors in the atmosphere.
Scientists may have finally found the cause of a mysterious disappearance of electrons dozens of miles above Earth.

It turns out that a layer of invisible meteor dust falling to Earth every day may be sucking up electrons coming from higher in the atmosphere, creating the so-called "D-region ledge," where the concentration of electrons suddenly plunges, Earle Williams, an atmospheric electrician at the Massachusetts Institute of Technology, said earlier this month at the annual meeting of the American Geophysical Union.

Physicists have long been hunting for the disappearing electrons, and had turned to everything from high-flying ice clouds to electrically charged water clusters in the atmosphere to explain the sudden drop-off in this region, he said.

"It's the most dramatic gradient anywhere in the ionosphere," Williams said, referring to the part of Earth's upper atmosphere where the D-region ledge is found. "It really is very conspicuous, so it's begging for an explanation."
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Bulb

Sixth-grader creates method for deriving highly secure, yet easily remembered passwords

David Funkhouser
Phys.org
Tue, 29 Dec 2015 00:00 UTC
password manager, mira modi
It's cheaper than a couple of subway rides, more powerful than almost any hacker (except maybe the NSA). And, if you think about it, not so hard to remember.

For $4, Mira Modi, 11, daughter of the Earth Institute's Vijay Modi and journalist Julia Angwin, will fix you up with a very secure password—actually a pass phrase of six words. She uses a well-known technique called Diceware that uses rolls of dice to select words at random from an encoded list.

The sixth-grader already has gotten a fair amount of attention for her enterprise, with an interview on NPR and stories in the New York Times, the ArsTechnica website and other media.

"Her business is doing fabulous," says her dad, who's a professor of mechanical engineering at Columbia University and a member of the Earth Institute faculty. "Her main issue right now is how to juggle the surge in demand with her schoolwork."

"All passwords are Diceware generated and contain six words," Mira says on her website. "I write the passwords by hand and do not keep a copy of what I have sent to you. The passwords are sent by U.S. Postal Mail, which cannot be opened by the government without a search warrant." She also recommends you alter the pass phrase slightly after she sends it to you.
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Butterfly

Research finds why old birds never go grey with age

Steve Connor
The Independent
Mon, 21 Dec 2015 01:26 UTC
structural feather color
© Andrew LeachFeather color produced by the refraction of light by an organized structure of keratin proteins in the feather. Here, blue is refracted and the remaining colors are absorbed by a layer of melanin.
Birds are able to produce intensely-coloured plumage by manipulating the way light is reflected from their feathers

Scientists have discovered why old birds never go grey with age, why green tree frogs turn blue when dead and why a red sweater might in future be washed with white shirts without turning them pink.

It all comes down to the novel way that many birds are able to produce intensely-coloured plumage by manipulating the way light is reflected from their feathers.

A study of a single barb in a jay's wing feather has revealed that it contains a network of sub-microscopic holes within a spongy matrix that accounts for the overall hue of the bird's plumage, scientists said.

The research has shown that the colour of a feather barb can turn from white to blue purely as a result of the change in the size of the holes within the spongy filling - the first time that bird colouration has been explained in such minute detail.

The study can explain why the brightly coloured feathers of many birds do not fade in sunlight or go grey with age, unlike human hair which relies on the continuous production of the dark pigment melanin as each hair grows from its follicle.

The results of the study might also lead to the invention of new types of "structural" colours, which are not based on pigments, for commercial paints and dyes that never fade in sunlight or run in the wash, the researchers said.

"This discovery means that in the future we could create long-lasting coloured coatings and materials synthetically," said Andrew Parnell of the University of Sheffield, the lead author of the study published in the journal Scientific Reports.
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Bizarro Earth

The world sees Americans as disorder-level narcissists

Eric Jaffe
City Lab
Fri, 11 Dec 2015 13:33 UTC
Actually, many Americans see themselves that way, too.

American flag in from of building
© jordi Borràs i Vivó / Flickr
Americans have a reputation for not exactly caring what the rest of the world thinks about them—a trait many public figures have lately been doing their best to enhance with each hysterical rant against refugees and immigrants. Turns out that message of self-absorption has long been received.

In a series of studies published this month, an international group of behavioral researchers finds a universal perception of Americans as exceptionally—even "problematically"—narcissistic. People living both inside and outside the U.S. rate the typical American much more highly on that measure than they rate themselves, their friends, or (for foreigners) the average citizen of their own country. In many cases those ratings were strong enough to meet clinical medical standards for a diagnosis of Narcissistic Personality Disorder.

Comment: For more on the Dunning-Kruger effect:

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