David Freeman
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David Freeman is the senior science editor of The Huffington Post in New York City and the host of Science Insider, a weekly radio program on an NPR station in Sharon, CT.

Entries by David Freeman

La découverte d'une "tuile" historique secoue le monde des mathématiques

(0) Comments | Posted August 21, 2015 | 12:14 PM

Une équipe de mathématiciens a bouleversé le monde des maths en découvrant un nouveau type de pentagone capable de "paver un plan", c'est-à-dire que les tuiles peuvent s'assembler sur une surface plane sans qu'elles ne se chevauchent ni ne laissent de trous.

Seuls quinze pentagones de ce type...

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La découverte d'une «tuile» historique secoue le monde des mathématiques

(0) Comments | Posted August 21, 2015 | 10:14 AM

Une équipe de mathématiciens a bouleversé le monde des maths en découvrant un nouveau type de pentagone capable de « paver un plan », c'est-à-dire que les tuiles peuvent s'assembler sur une surface plane sans qu'elles ne se chevauchent ni ne laissent de trous.

Seuls quinze pentagones de ce type...

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Historic 'Tile' Discovery Gives Math World A Big Jolt

(1) Comments | Posted August 18, 2015 | 10:02 PM


A team of mathematicians has wowed the math world with their discovery of a new kind of pentagon capable of "tiling a plane"--that is, fitting together on a flat surface without overlapping or leaving any gaps.


It's said to be only the fifteenth such pentagon ever...

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These Macro Photos Reveal The Awesome Diversity Of Human Eyes

(0) Comments | Posted August 18, 2015 | 2:57 PM


It sees. It cries. It helps us communicate. Yes, the human eye is one outstanding organ. But what do you see when you look into someone’s eyes?


Most of us focus on their color. But give a really close look and you’ll see at once that our...

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Freaky 'Sea Monster' Recovered From Centuries-Old Shipwreck

(0) Comments | Posted August 13, 2015 | 12:52 PM

The fearsome-looking figurehead of a warship that went down in the Baltic Sea more than 500 years...

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21명의 남자들이 과학을 위해 자위를 한 결과는?(연구)

(0) Comments | Posted August 10, 2015 | 6:13 PM

다양함은 삶의 즐거움이라고들 한다. 오하이오의 과학자들이 진행한 도발적인 새 연구에 의하면 인간의 섹스와 번식의 세계에서도 그 말은 진리다.

21명의 남성과 포르노의 도움을 받아, 우스터 대학의 연구자들은 남자들은 ‘새로운 여성 자극’을 보며 자위할 때 더 빨리 사정하고 품질이 우수한 정자를 더 많이 생산한다는 것을 밝혔다.

쉽게 말해, 전에 마주친...

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Mysterious 'Stonehenge' Monolith Found Off Sicily's Coast

(1) Comments | Posted August 10, 2015 | 2:50 PM


In deep water off the coast of Sicily, scientists have found a large and very mysterious monolith that is believed to have been hewn from rock some 10,000 years ago.


"Considering its shape and length, it can be called a Stonehenge-type monolith, but its age is remarkably...

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Άνδρες αυνανίστηκαν για χάρη της επιστήμης. Δείτε τι έδειξε η έρευνα

(9) Comments | Posted August 8, 2015 | 1:52 PM

Έρευνα την οποία πραγματοποίησαν επιστήμονες του The College of Wooster έδειξε ότι οι άνδρες εκσπερματώνουν γρηγορότερα και παράγουν περισσότερο και υψηλότερης ποιότητας σπέρμα όταν...αυνανίζονται με «πρωτότυπο θηλυκό ερέθισμα»!

Εν ολίγοις, ερεθίζονται όταν βλέπουν σέξι γυναίκες τις οποίες δεν έχουν ξαναδεί στο παρελθόν. Ωστόσο, όπως σημειώνεται σε σχετικό...

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Men Masturbated For Science, And Here's What Came Of It

(0) Comments | Posted August 4, 2015 | 2:35 PM

 They say variety is the spice of life, and provocative new research by scientists in Ohio suggests that that holds true in the world of human sex and reproduction.

With the help of 21 men and some porn videos, The College of...

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Eerie New Asteroid Video Reveals Giant 'Space Peanut'

(0) Comments | Posted August 3, 2015 | 12:44 PM

With the help of a pair of giant radio telescopes, scientists have captured eerie new video of an asteroid as it whizzed by Earth last month.

Known formally as 1999 JD6, the space rock is being called a "space peanut" because of its elongated shape and twin lobes.

What explains the lobes?

One possibility is that a couple of "big chunks" came together at some point, asteroid expert Dr. Amy Mainzer, principal investigator for NASA's NEOWISE space telescope program, told The Huffington Post in an email. Another possibility, she said, is that the asteroid--which is about 1.2 miles across at its widest point--is what's left over after a larger asteroid survived some kind of impact.

In any case, the peanut shape isn't particularly unusual. 

"Radar imaging has shown that about 15 percent of near-Earth asteroids larger than 600 feet [about 180 meters], including 1999 JD6, have this sort of lobed, peanut shape," Dr. Lance Benner of NASA's Jet Propulsion Laboratory in Pasadena, Calif. and leader of the space agency's asteroid radar research program, said in a written statement.

(Story continues below image.)

Radar images of asteroid 1999 JD6 as seen on July 25, 2015. 

Technically a "contact binary" asteroid, 1999 JD6 made its closest approach to Earth at 12:55 a.m. EDT on July 25, when it passed by our planet at a distance of about 3.5 million miles. That's about 19 times the distance from the Earth to the moon.

The video is made up of images captured over an eight-hour period. NASA created it via a technique known as bistatic observation: the 70-meter Deep Space Network antenna at Goldstone, Calif. beamed a radar signal at 1999 JD6, and the reflected signal was received by the Green Bank Telescope in West Virginia.

Mainzer said radar imaging is a great tool for observing asteroids--at least when conditions are right.

"Because radar waves have to travel to the object, reflect off of it, then travel back to our receivers, the asteroids have to get pretty close to be able to get this kind of detail," she said in the email. "But when the asteroids do get close enough, radar delivers images that are matched in detail only by spacecraft visits, which are a lot more expensive."

While 1999 JD6 poses no immediate threat to us, watching it tumble noiselessly in the video is a reminder that somewhere out there, a dangerous asteroid may be on a potentially cataclysmic collision course with Earth. It's happened many times before, and there's no doubt it will happen again

Lucky for us, scientists are working hard not only to detect potentially dangerous asteroids but also to eliminate the threat they pose.

One strategy on the drawing board is the so-called "gravity tractor"-- a space probe that would be launched toward an asteroid and use gravity to steer it away from the...

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Hubble Spies Dying Star's Final 'Moments'

(0) Comments | Posted July 31, 2015 | 3:00 PM


In the quarter-century that it's been eyeing the cosmos, the Hubble Space Telescope has taken some pretty spectacular photos. But few are as dramatic as a new image (above) of what the space agency termed "a dying star's final moments."


In more down-to-Earth...

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Super-Intense Auroras Discovered On Strange Alien World

(0) Comments | Posted July 30, 2015 | 11:51 PM


For the first time ever, the celestial light shows known as auroras have been detected outside our solar system.


The auroras were detected not on an exoplanet but on a brown dwarf, one of a class of objects that are too big to...

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Biólogo desmonta - peça por peça - o quebra-cabeça criado pelos racistas

(2) Comments | Posted July 27, 2015 | 11:03 PM

angela davis

Não há dúvidas de que diferentes grupos de pessoas podem parecer muito diferentes uns dos outros. Mas, para antropólogos e sociólogos contemporâneos, a noção de que existem distintas “raças” de seres humanos, cada uma com atributos específicos, não faz muito sentido.

Essa lógica é compartilhada...

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Scientists Figure Out Pendulum Clock Puzzle That Dates Back Centuries

(0) Comments | Posted July 26, 2015 | 7:36 PM

Well, it's about time!

After more than three centuries, scientists say they have figured out why pendulum clocks hung on the same wall tend to sync up--with one clock's pendulum swinging to the left just as the other swings right.

The strange phenomenon was first observed in 1665 by Christiaan Huygens (1629-1695), according to LiveScience. No matter how the clocks started, the Dutch scientist noticed that within about 30 minutes their pendulums wound up swinging in precisely opposite directions.

(Story continues below image.)

Over the years various explanations were offered, including the idea that the pendulums sync up as a result of tiny air currents they create, AFP reported.

But according to a new paper published on July 23 in the journal Scientific Reports--which builds on earlier research, including a study published in 2002--this is the correct explanation: sound waves generated by the movement of one pendulum travel through the wall to perturb the movement of the other until the pendulums are moving in opposition.

As Dr. Henrique M. Oliveira, a University of Lisbon mathematician and one of the study's co-authors, told The Huffington Post in an email, "The two clocks interact, giving two 'kicks,' one in one direction and another one in the opposite direction... Only when the clocks are at phase opposition the effects of the perturbation cancel" and the pendulums swing in opposite directions.

(Story continues below image.)

Oliveira said he and study co-author Dr. Luis V. Melo (pictured above), a physicist at the university, reached their conclusion after developing a complex mathematical model and then confirming it experimentally with a pair of clocks hung on an aluminum rail.

The finding shows that "very small interactions can add up and in the end synchronize very large systems," Oliveira said. The same basic principle is seen in other disciplines, he said, including economics, electronics, and biology--for instance, when cells in the heart sync up to create the heartbeat or brain cells sync up to trigger seizures in people with epilepsy.

Huygens is credited with creating the first pendulum clock in 1656, according to AFP. At the time it was the most accurate timepiece ever made, gaining or losing less than one minute a day.

The most accurate clocks today are a bit more accurate. As Vice reported last April, one developed recently by physicists from the National Institute of Standards and Technology and the University of Colorado is accurate to within one second every 15 billion years.

...
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햇빛이 비치는 부분의 지구 사진이 사상 처음으로 공개되다(사진)

(0) Comments | Posted July 20, 2015 | 9:57 PM

earth


우주에서 지구를 찍은 사진은 그리 새로운 건 아니다. 하지만 이 사진은 정말 새로운 것이다.


나사의 심우주기후관측위성(DSCOVR)이 햇빛이 비치는 지구의 절반 사진을 최초로 촬영해 공개했다.


2015년 7월 6일 지구다색이미징카메라(EPIC)으로 지구에서 약 100만 마일((160만km) 거리에서 촬영한...

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Dramatic Photo Of Earth Is Probe's First To Show Entire Sunlit Side Of Planet

(0) Comments | Posted July 20, 2015 | 11:05 AM


Dramatic photos of Earth from space are nothing new, but few are as dramatic as this. NASA's Deep Space Climate Observatory (DSCOVR) satellite has captured its first photo to show the entire sunlit side of the Earth.


The space agency called the eye-popping image "EPIC" -- a...

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New Pluto Photos Show High Mountains, Giant ‘Tail'

(0) Comments | Posted July 17, 2015 | 10:56 AM

Hungry for more about Pluto? No worries. Today NASA scientists served up another helping of photos and scientific findings from the New Horizons spacecraft, which made its historic flyby of the far-flung dwarf planet on July 14.

Previously released images revealed evidence of high peaks on Pluto and a deep canyon and a mysterious mountain on its biggest moon, Charon.

What will we see today? Scroll down to find out.

Pluto'€™s moon Nix. It'€™s about 25 miles across.

Graphic showing concentrated region of carbon monoxide.

Icy, frozen plains on Pluto.

Icy plains of Pluto 

Frozen plains of Pluto--vast and craterless. Similar surfaces can be seen on glaciers here on Earth.

Section of Pluto'€™s surface showing newly named mountains.

“We know the atmosphere is nitrogen,” New Horizons co-investigator Fran Bagenal, said of Pluto. Pluto has a tail of charged...

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Mystery Of Super-Hot 'Blue Hook' Stars Finally Solved

(58) Comments | Posted July 9, 2015 | 8:40 AM

Astronomers may have just solved a mystery 10 billion years in the making.

It has to do with so-called "blue hook" stars, which have less than half the mass of the sun but burn 10 times hotter and are far more luminous. No one was ever able to explain...

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The Science Of Race, Revisited

(318) Comments | Posted July 6, 2015 | 9:03 AM

There's no doubt that different groups of people can look very different from one another. But to contemporary anthropologists and sociologists, the notion that there are distinct "races" of human beings, each with its own specific attributes, doesn't make much sense.

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NASA 로버가 본 화성의 ‘피라미드'는 보기와는 다르다

(0) Comments | Posted June 30, 2015 | 5:21 PM

NASA의 큐리오시티 로버는 화성의 피라미드 사진을 찍었다. 적어도 일부 불가사의 애호가들은 그렇게 생각하는 것 같다.


파라노멀 크루시블이 새로 올린 유튜브 영상은 로버의 마스트캠 카메라가 2015년 5월 6일에 찍은 사진에 ‘거의 완벽한 디자인과 모양’을 갖춘 피라미드가 나오고, 이것은 ‘지적인 디자인의 결과이고 빛과 그림자의 눈속임은 절대...

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