Thursday 10 October 2013

This Is the Average Man's Body

George Maat, a professor emeritus of anthropology at Leiden University Medical Center in the Netherlands, has said that within another 50 years, the Dutch Todd could be six-foot-three. Several years ago the Netherlands was compelled to increase building code standards for door frames to 7-feet, 6.5-inches. If, in the last half-century, the American physical form has been expelled from international imagination as an ideal, we might presently look at the situation not just as failure, but with optimism for what we might become.

URL: http://feedproxy.google.com/~r/TheAtlantic/~3/Bf-Sa6Bmtxg/story01.htm

Um, Where Did This Little Orphan Planet Come From?

How do planets—ours, and the others that stud the universe—actually form?

Our current, best knowledge posits that planets emerge from the formation of stars. Through a process like this:

A star and its planets form out of a collapsing cloud of dust and gas within a larger cloud called a nebula. As gravity pulls material in the collapsing cloud closer together, the center of the cloud gets more and more compressed and, in turn, gets hotter. This dense, hot core becomes the kernel of a new star.

Meanwhile, inherent motions within the collapsing cloud cause it to churn. As the cloud gets exceedingly compressed, much of the cloud begins rotating in the same direction. The rotating cloud eventually flattens into a disk that gets thinner as it spins, kind of like a spinning clump of dough flattening into the shape of a pizza. These "circumstellar" or "protoplanetary" disks, as astronomers call them, are the birthplaces of planets.

As a disk spins, the material within it travels around the star in the same direction. Eventually, the material in the disk will begin to stick together, somewhat like household dust sticking together to form dust bunnies. As these small clumps orbit within the disk, they sweep up surrounding material, growing bigger and bigger. The modest gravity of boulder-sized and larger chunks starts to pull in dust and other clumps. The bigger these conglomerates become, the more material they attract, and the bigger they get. Soon, the beginnings of planets—"planetesimals," as they are called—are taking shape.

Straightforward enough: cosmic pizzas, basically, with little pepperonis gradually taking shape. Here's a potential wrinkle in that process, though—one that takes the form of an adorable little orphan planet that astronomical renderers have decided is a perky shade of purple. That planet, hanging out some 80 light-years away from Earth, seems to have formed 12 million or so years ago—relatively recently in planet-formation terms. The planet, PSO J318.5-22, has six times the mass of Jupiter. It has properties that make it similar to the gas giants that are generally found orbiting young stars.

Except: The planet is free-floating. No host star. No known origin story. The Orphan Annie of the cosmos.

"We have never before seen an object free-floating in space that that looks like this," Michael Liu, of the Institute for Astronomy at the University of Hawaii at Manoa, told PhysOrg of the planet. "It has all the characteristics of young planets found around other stars, but it is drifting out there all alone."

The discovery paper for PSO J318.5-22—the paper terms the planet, delightfully, "The Extremely Red, Young L Dwarf"—is being published in Astrophysical Journal Letters. The paper was authored by Liu, along with 18 other co-authors.

PSO J318.5-22 isn't the first planet to be found without a host star. Astronomers have, in the past 10 years or so, discovered 1,000 or so of such extrasolar planets (or, more precisely, they have inferred their existence through observations of other cosmic bodies). Last year, scientists announced their discovery of CFBDSIR2149, believed to be a similarly rogue (or, less judgmentally, "homeless" or "orphan") planet. Such planets, scientists speculate, can form in one of two ways: They're either formed within solar systems according to the process above and then ejected—or they form independently in interstellar space.

But that ambiguity makes these seemingly homeless planets especially intriguing to astronomers: If it's the latter formation process, how exactly would these planets form? Can you have the chicken of the planet without the egg of a host star?

There have been only a few homeless planets that we've thus far directly imaged in the way the paper's authors have been able to image PSO J318.5-22. And while the planet is similar in mass and color and energy output to those planets, it differs in a significant way: Its mass is much, much lower than those planets'. It may even be, Liu and his colleagues say, one of the lowest-mass free-floating objects we've yet discovered. Perhaps the very lowest.

And that means that PSO J318.5-22, the little orphan planet, could be a great adoptee for scientists. "Planets found by direct imaging are incredibly hard to study," Niall Deacon, the paper's co-author, explained, "since they are right next to their much brighter host stars." A planet that's not orbiting a star, however, doesn't have that drawback. "It is going to provide a wonderful view into the inner workings of gas-giant planets like Jupiter shortly after their birth."

It also, in the meantime, serves as a reminder of how lonely and cold the cosmos can be. Here is a planet of unknown origin, of unknown lineage, in utter solitude. As Dr. Liu put it: "I had often wondered if such solitary objects exist, and now we know they do."

Via arxiv.org and Phys.org

URL: http://feedproxy.google.com/~r/TheAtlantic/~3/_0Ywa2YLRlY/story01.htm

To Fix Wikipedia’s Gender Imbalance: A Big Editing Party?

To Fix Wikipedia's Gender Imbalance: A Big Editing Party?

Next week, students, faculty and members of the public will gather in a room at Brown University. They will sit down, open their laptops—enjoy some light snacks and drinks—and then, for five and a half hours, edit Wikipedia.

Specifically, they'll be editing Wikipedia to add and improve entries about women in science, technology, and math. Their "Edit-a-Thon," reported today by the Chronicle of Higher Education, will fall on the fifth annual Ada Lovelace Day, an international celebration of women's contribution to technology. Lovelace worked on and wrote algorithms for Charles Babbage's Analytical Engine in the early 19th century, a mechanical predecessor to the computer, making her the world's first computer programmer.

The Lovelace-themed Edit-a-Thon will help those unused to editing the encyclopedia: Its first hour will focus on the basics of Wikipedia writing. And the event's homepage already has a long list of articles which need improvement or don't exist yet. No Wikipedia entry exists, for instance, for Ingeborg Homchair, who won the 2013 Lasker Award for co-inventing the modern cochlear implant, the first device to "substantially [restore] a human sense with a medical intervention."

Wikipedia has historically struggled with a gender imbalance that mars both its content and its editors. A 2011 New York Times story suggested only 15 percent of its editors might be women. When data researcher Santiago Ortiz scoured Wikipedia to find articles edited by more women than men, he could only locate "Cloth menstrual pad." (His research made for a great if unfortunate visualization, though.)

Since then, Wikipedians have tried to close the gender gap more directly. A meet-up and edit-a-thon earlier this year in Washington, D.C., for instance, sought to add and improve the entries of women in the arts en masse. Next week's Edit-a-Thon will again chip away at the imbalance, albeit slowly. But Wikipedia, unlike other knowledge sources, can be edited by the public, and its errors and shortcomings can be ameliorated—incrementally, but surely—by the same public.

URL: http://feedproxy.google.com/~r/TheAtlantic/~3/aSFXy4T_3Vg/story01.htm

According to Ted Cruz's 'Unskewed' Poll, Republicans Are Winning

Don't worry, Ted Cruz is telling his fellow Republicans, about that new Gallup Poll showing that the GOP's favorability rating has sunk to an all-time low. And ignore the National Journal, Washington Post, CBS News, AP, CNN, and Pew surveys showing that Americans are mostly blaming Republicans for the government shutdown.

Those are all wrong, the Texas senator is telling his GOP colleagues, because he has his own poll, and it shows the GOP is winning.

As David Drucker reports at The Washington Examiner, Cruz argued to Republicans at a closed-door lunch on Wednesday that the campaign he led to shutdown the government over Obamacare has bolstered the GOP's political position, rather than hurt it. Cruz says he knows this because he paid for his own poll, conducted by his own partisan pollster, who was on hand to explain the results to his skeptical colleagues.

Despite all that, the poll was not much rosier than all public polls, showing that the public blames Republicans for the shutdown by a 7-point margin.

To Cruz, as Drucker writes, this shows that "Republicans are in a much better position than they were during the 1995 shutdown because this impasse is defined by a disagreement over funding for the Affordable Care Act as opposed to a general disagreement over government spending."

Maybe Cruz is right, and maybe Republicans are "winning," and maybe his pollster is better than everyone else's. Maybe.

But if not, then he's falling victim to same fallacy Republicans ran into leading up the 2012 election, when Mitt Romney was reportedly so convinced that he was going to win that he didn't even bother writing a concession speech. The national public opinion data was pretty clearly showing the opposite, but some on the right stuck to the echo chamber, where the polls were unskewed and the vibes were good, leading to Dick Morris predicting as late as 8 p.m. on election night that Romney would still win big, and later to an on-screen meltdown from Karl Rove when Romney lost Ohio.

The fancy term for this is "epistemic closure," but basically it means only believing what you want to believe and ignoring the rest. That may be why Cruz thought that Barack Obama would ever agree to defund his signature legislative accomplishment. Or thinking, as a large number of Republican lawmakers seem to, that failing to raise the debt ceiling would be no big deal.

But unlike the election, if Cruz is wrong and breaching the debt ceiling is as catastrophic as most economists are predicting, this time the whole country loses.