Author: Internship

by Alex Carter

You know what it’s like: You live somewhere all your life but never realize just how great it is until someone comes to visit. While it’s just a shame we don’t get any visitors to marvel at all the peculiarities of our home planet, here are five facts you might still appreciate.

1. EARTH’S A GIANT DYNAMO.

The core of the Earth is a solid lump of nickel and iron, rotating in a sea of molten iron and nickel. This rotation functions the same way winding up a hand-held generator does, giving Earth an enormous magnetic field that extends up to 50,000 kilometers out into space. This magnetic field is crucial for life on Earth, as without it we would be exposed to the full force of the Sun’s radiation. As well as causing cancers and other radiation-aggravated conditions, the radiation’s sheer force would blow our atmosphere into space, as happened with Mercury, and to a lesser extent, Mars. Instead, charged particles are (mostly) harmlessly deflected away, giving rise to the auroras.

It’s not all good though: Any particles that hit the Earth head-on tend to get trapped in the field and can’t get out. These so-called Van Allen Radiation Belts can pose a hazard for astronauts who leave low Earth orbit.

2. IT’S THE DENSEST PLANET IN THE SOLAR SYSTEM.

While Earth may not be the biggest planet in the system, it is the biggest rocky planet in the solar system, and also the densest. Therefore, Earth has by far the highest surface gravity of any terrestrial object in the solar system. This is both a blessing and a curse.

The reason for the high density is the large deposits of heavy elements in the Earth’s makeup. Elements such as lead and uranium are much rarer on other worlds, which gives us a huge advantage in the amount and variety of construction materials available here on Earth. The high gravity has also demanded that humans develop the reflexes and endurance necessary to cope with such gravity, meaning we are far more durable than the potential delicately boned, sloth-like creature we could be had we evolved in low gravity.

Unfortunately, that high gravity makes Earth the worst place in the solar system for space exploration. The sheer cost of overcoming Earth’s gravity during every launch has been the single biggest barrier to space travel. To put it into perspective, if the Earth only had the same gravity as the Moon, a typical airplane would be fast enough to get into orbit. The human race might have explored much more of the solar system using present day technology if we had lower gravity—although, of course, the weakness of low-gravity humans might have proven to be an equal barrier.

3. THE MOON IS DISPROPORTIONATELY HUGE.

Most planets in the solar system have moons, and our moon may not be the biggest of them, but in comparison to Earth’s size, it’s enormous. Most scientists think that rather than coalescing on its own like the other large moons, it was violently shorn off Earth billions of years ago by a collision between Earth and another planet. The impact—with a planet about the size of Mars—liquified Earth in the heat, and the Moon broke off, gradually cooling into a ball of rock. New research suggests that not just one but multiple collisions may be responsible for its formation.

The Moon’s size and distance are a giant cosmic coincidence, allowing us on Earth’s surface to experience total eclipses, annular eclipses, and partial eclipses, all from the comfort of our own planet. If the Moon were smaller or farther away, we wouldn’t see any sort of eclipse at all.

The Moon is also an important tool for scientists trying to better understand Earth’s composition. Starting with all the same raw materials, except for the magnetic field, the Moon cooled, geological activity stopped, and the solar wind blew away what atmosphere there was. Now, the surface is littered with craters which could not be healed, like scars. And the razor sharp soil sticks to everything, even the radiation coming in from the Sun. (Seems like we got the better end of that deal.)

4. WE LIVE ON A GIANT NUCLEAR FURNACE.

Take a spade to many points on the Earth’s crust and you might dig up a selection of radioactive elements. While we might think of the Earth’s magnetic field as protecting us from radiation, it does little to protect us from what’s right under our feet.

Most of the radioisotopes on Earth reside in the core, where the heat from their decay keeps the core molten, the tectonic plates moving, and the dynamo deep in the Earth rotating. If it weren’t for radioisotopes, the core would cool, the magnetic field would disappear, and the Earth would slowly become uninhabitable. There is another consequence of all these radioactive elements, though. In Oklo, Gabon, it was discovered that the uranium mines contained significantly less uranium-235 (the kind used in nuclear reactors and weapons) than the other isotopes. The startling conclusion was that the reserves had been used over millions of years in a naturally occurring nuclear reactor.

5. IT IS THE ONLY PLANET KNOWN TO HAVE LIFE.

Despite current attempts to find other habitable planets, Earth is the only place in the universe we can be sure that there is life. With liquid water, oxygen, and plenty of sunlight, we really lucked out. But with recent findings of water on Europa and Callisto, Jupiter’s moons, we have new hope that someday we’ll find another planet capable of supporting life.

by Aliya Whiteley

Just when you think there’s nothing new to be seen, done, or explored upon this Earth, you get reminded how vast and unconquerable the planet actually is. For instance, no matter what the Mother Superior sings in The Sound Of Music, we are far from climbing every mountain. There are plenty of unclimbed mountains in the world for a number of reasons; we don’t even know for sure how many, since the historical record is vague.

But there’s general agreement that Gangkhar Puensum, the highest mountain in Bhutan at 24,836 feet and the 40th highest mountain in the world, can probably be described as the highest unclimbed mountain. Why hasn’t it been climbed? That’s partly due to its incredibly remote nature, and the fact that despite its size, it was, for quite some time, difficult to find. It was first mapped in 1922, but later maps marked it in different positions, and at various heights. Bhutan has never conducted its own official survey.

But now we have satellites and GPS—so surely it should be easy to track down and climb, right? Well, Gangkhar Puensum also lies in disputed political territory, on the border between Bhutan and Tibet. Bhutan says the mountain is entirely within its territory, but China claims that half of it lies in Tibet, and is therefore Chinese.

Add to this disagreement the fact that in 1994 Bhutan banned the climbing of all mountains higher than 19,800 feet out of respect for local religious beliefs—and in 2003 prohibited mountaineering entirely—and you have a lot of reasons why Gangkhar Puensum remains unclimbed. It’s not that people haven’t tried; for instance, there were four expeditions in the 1980s that were all unsuccessful.

The last attempt made on the mountain didn’t even reach it; China gave permission for a Japanese expedition to attempt Gangkhar Puensum in 1998, and Bhutan then revoked the permit. Eventually the expedition went off and climbed a nearby mountain instead. It’s called Liankang Kangri, lies in Tibetan territory, and is a subsidiary peak of Gangkhar Puensum that is only a few hundred feet smaller. Guess what? Before the Japanese expedition was successful in its climb, that mountain was unclimbed too.

by Kenny Hemphill

You might already know that in 1947, U.S. test pilot Chuck Yeager was the first person to break the sound barrier in a Bell X-1 named the Glamorous Glennis. But aircraft aren’t the only things that break the sound barrier. Here are a few other items that may surprise you.

1. PEOPLE

When Felix Baumgartner jumped out of a balloon 24 miles above New Mexico in 2012, he broke more than the world record for the highest-ever freefall. About a third of the way down, Baumgartner reached Mach 1.25 or 843.6 mph, and in doing so became the first person to break the sound barrier while in freefall.

Having beaten a freefall record that had existed for 52 years, however, Baumgartner only held it for two years, when it was beaten again by Google exec Alan Eustace. He also broke the sound barrier, though he didn’t hit as impressive a maximum speed as Baumgartner, reaching a measly 822 miles per hour, or Mach 1.23.

2. PING PONG BALLS

Anyone who’s watched the top table tennis players in action knows they hit the ball hard and that it travels almost too quickly for the eye to see. But even that pales in comparison to the air-powered cannon built in 2013 by students at Indiana’s Purdue University, which fired ping pong balls at more than 900 mph. “You can get really, really high accelerations, the ball comes out of the barrel intact and doesn’t break until it actually hits something,” mechanical engineer Mark French Inside Science. The cannon used a vacuum pump to suck the air from a sealed tube, the air rushed to a nozzle shaped like an hour glass, and the nozzle propelled the ping pong balls at supersonic speed—about 919 mph. Remarkably, given their light weight and poor aerodynamics, the ping pong balls delivered as much energy to their target as a brick falling several stories.

3. WHIPS

You know that crack a bullwhip makes when it’s wielded in anger by an expert? That’s a sonic boom, the shockwave created when the tip of the whip breaks the sound barrier. Or at least, that had been the presumption until researchers at the University of Arizona spoiled it for everyone.

They were puzzled as to why, if the crack is a sonic boom, it doesn’t occur until the whip’s tip is traveling at almost twice the speed of sound. It turns out that the cracking noise is actually created by a loop traveling along the whip, picking up speed. And when it reaches the speed of sound, it creates a sonic boom.

4. A TOWEL

Snapping a towel in the changing room is dangerous—you could, in all seriousness, take someone’s eye out. The reason it’s so dangerous has partly to do with the speed the end of the towel is traveling. Like a bullwhip, it goes very fast indeed.

In 1993, a group of students at North Carolina School of Science and Mathematics set out to prove that a properly whipped towel could break the sound barrier. They rigged up a high-speed photography kit that would allow them to measure the distance the tip of the towel was traveling at the moment they thought the barrier would be broken. After the experiment, it seemed like they had managed to break the barrier—but the students felt their results were inconclusive.

So they tweaked the experimental setup (and, according to some sources, swapped the towel for a cut down bedsheet) which eventually allowed them to break the sound barrier. But there was another caveat: The team cautioned that they still got snaps when it didn’t appear that they had broken the barrier. The theory was that their camera wasn’t fast enough to catch subsequent supersonic moments, but it remains a mystery.

5. AIR

Here’s an odd one to finish with. According to one study, when a rock or other such object is dropped into water, an hourglass-shaped cavity of air is created, which then ejects the air at speeds faster than the speed of sound.

There’s a lot of life under our feet—and now we can appreciate that more than ever. After three years, a multi-disciplinary team of 121 scientists put together the new Global Soil Biodiversity Atlas. It showcases the bacterial, fungal, and animal life that together comprise an estimated quarter of all global biodiversity.

Photographer Seph Lawless snapped these pictures inside two abandoned Ohio shopping malls. His work captured both the beauty and the melancholy of these modern ruins before they were demolished.

Ancient Greek and Roman soldiers used football-shaped lead bullets as ammunition for their slingshots. These projectiles could wreak havoc on their targets, but the soldiers weren’t content to merely wound their enemies. They also taunted them by inscribing insults and sarcastic jokes on their bullets.