What Are the Northern Lights?

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iStock

Over the centuries, many have gazed up at one of the Earth’s most fascinatingly beautiful natural wonders: the Northern Lights. In the past couple of weeks, some lucky American stargazers have gotten the chance to see them from their very own backyards—and could again this week, according to Thrillist. But what are they?

Before science was able to get a read on what exactly was happening in the night sky, ancient tribes had their own theories for what caused the jaw-dropping light show. Many early beliefs had roots in religion, such as that the light was a pathway souls traveled to reach heaven (Eskimo tribes) or that the light was an eternal battle of dead warriors (Middle-Age Europe). Early researchers were a bit more reasonable in their approximations, and most surrounded the idea of the reflection of sunlight off the ice caps. In 1619, Galileo Galilei named the lights the aurora borealis after Aurora, the Roman goddess of morning, after concluding they were a product of sunlight reflecting from the atmosphere.

Today, scientists have come to the general agreement that the lights are caused by the collision of electrically charged solar particles and atoms from our atmosphere. The energy from the collisions is released as light, and the reason it happens around the poles is because that's where the Earth’s magnetic field is the strongest. In 2008, a team at UCLA concluded that “when two magnetic field lines come close together due to the storage of energy from the sun, a critical limit is reached and the magnetic field lines reconnect, causing magnetic energy to be transformed into kinetic energy and heat. Energy is released, and the plasma is accelerated, producing accelerated electrons.”

"Our data show clearly and for the first time that magnetic reconnection is the trigger," said Vassilis Angelopoulos, a UCLA professor of Earth and Space Sciences. "Reconnection results in a slingshot acceleration of waves and plasma along magnetic field lines, lighting up the aurora underneath even before the near-Earth space has had a chance to respond. We are providing the evidence that this is happening."

The best time to see the Northern Lights is during the winter, due to the Earth’s position in relation to the sun (shorter days means darker night skies). And by the way, it’s not just the North Pole that puts on a show—there are Southern Lights, too. There are also aurora borealis on other planets—including Mars—so rest assured that future generations born “abroad” will not miss out on this spectacular feat of nature.

Haven’t seen them yet? Traditionally, the best places to catch a glimpse of the Northern Lights are in Iceland, Sweden, Norway, Finland, Greenland, northern Canada, and Alaska. Maybe you'll get lucky this week and sneak a peek from your very own window. Check out Aurorasaurus for regular updates on where they are showing.

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This Course Will Teach You How to Play Guitar Like a Pro for $29

BartekSzewczyk/iStock via Getty Images
BartekSzewczyk/iStock via Getty Images

Be honest: You’ve watched a YouTube video or two in an attempt to learn how to play a song on the guitar. Whether it was through tabs or simply copying whatever you saw on the screen, the fun always ends when friends start throwing out requests for songs you have no idea how to play. So how about you actually learn how to play guitar for real this time?

It’s now possible to learn guitar from home with the Ultimate Beginner to Expert Guitar Lessons Bundle, which is currently on sale for $29. Grab that Gibson, Fender, or whatever you have handy, and learn to strum rhythms from scratch.

The strumming course will teach you how to count beats and rests to turn your hands and fingers into the perfect accompaniment for your own voice or other musicians. Then, you can take things a step further and learn advanced jamming and soloing to riff anytime, anywhere. This course will teach you to improvise across various chords and progressions so you can jump into any jam with something original. You’ll also have the chance to dive deep into the major guitar genres of bluegrass, blues, and jazz. Lessons in jam etiquette, genre history, and how to read music will separate you from a novice player.

This bundle also includes courses in ear training so you can properly identify any relative note, interval, or pitch. That way, you can play along with any song when it comes on, or even understand how to modify it into the key you’d prefer. And when the time comes to perform, be prepared with skilled hammer-ons, pull-offs, slides, bends, trills, vibrato, and fret-tapping. Not only will you learn the basic foundations of guitar, you’ll ultimately be able to develop your own style with the help of these lessons.

The Ultimate Beginner to Expert Guitar Lessons Bundle is discounted for a limited time. Act on this $29 offer now to work on those fingertip calluses and play like a pro.

 

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Why Are Common Graves Called Potter’s Fields?

Graves in potter's fields are sometimes marked with blank headstones or crosses.
Graves in potter's fields are sometimes marked with blank headstones or crosses.
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For centuries, regions around the world have maintained common graves called potter’s fields, where they bury unidentified victims and impoverished citizens who couldn’t afford their own cemetery plots. The term potter’s field has been around for just as long.

The earliest known reference to a potter’s field is from the Gospel of Matthew, which historians believe was written sometime during the 1st century. In it, a remorseful Judas gives the 30 silver coins he was paid for betraying Jesus back to the high priests, who use it to purchase a “potter’s field” where they can bury foreigners. It’s been speculated that the priests chose land from a potter either because it had already been stripped of clay and couldn’t be used for farming, or because its existing holes and ditches made it a particularly good place for graves. But Matthew doesn’t go into detail, and as the Grammarphobia Blog points out, there’s no evidence to prove that the original potter’s field was ever actually used for its clay resources—it could’ve just been a parcel of land owned by a potter.

Whatever the case, the term eventually caught on as English-language versions of the Bible made their way across the globe. In 1382, John Wycliffe translated it from Latin to Middle English, using the phrase “a feeld of a potter,” and William Tyndale’s 1526 Greek-to-English translation of the passage featured “a potters felde,” which was altered slightly to “potters field” in King James’s 1611 edition.

Around the same time, a new definition of potter was gaining popularity that had nothing to do with pottery—in the 16th century, people began using the word as a synonym for tramp or vagrant. According to the Oxford English Dictionary, it was first written in a 1525 Robin Hood tale, and William Wordsworth mentioned it in his 1798 poem “The Female Vagrant.” It’s likely that this sense of the word helped reinforce the idea that a potter’s field was intended for the graves of the unknown.

It’s also definitely not the only phrase we’ve borrowed from the Bible. From at your wit’s end to a fly in the ointment, here are 18 everyday expressions with holy origins.

[h/t Grammarphobia Blog]