Eneas de Troya, Wikimedia Commons // CC BY-SA 2.0
Eneas de Troya, Wikimedia Commons // CC BY-SA 2.0

The 'North Star' Is Actually Three Stars

Eneas de Troya, Wikimedia Commons // CC BY-SA 2.0
Eneas de Troya, Wikimedia Commons // CC BY-SA 2.0

As savvy travelers have known for millennia, above the equator you don’t need GPS or a compass to figure out which way is north. All you need is a clear night sky.  

From our perspective, the stars appear to slowly move in vast circles  around what seems to be a fixed point of light more or less directly above the North Pole. This beacon happens to line up almost perfectly with the invisible axis on which Earth rotates (though it’s still about .7 degrees off target). This is, of course, the North Star, also known as Polaris (and many other aliases).

But here’s the thing: Polaris isn't one star. It’s three.

Located in the constellation Ursa Minor, Polaris is actually a triple star system. The first indication that the North Star was more than it appeared to be came in 1780, when William Herschel examined it through his telescope. Instead of spotting a single star, Herschel (who a year later discovered Uranus) instead found two close neighbors.

These stars are an odd couple. Polaris A is a supergiant roughly six times more massive and 2000 times brighter than our own Sun that dwarfs its companion, Polaris B. They're 323 light-years away, as scientists calculated in 2012. (Previous estimates had put them 434 light-years from Earth.) The vast distance blurs their boundaries to the naked eye. 

In 2006, astronomers using the Hubble telescope realized this duo was actually a trio when they spotted a third, relatively diminutive star nearby, which they dubbed Polaris Ab. As you might expect, these three exert a huge gravitational force on each other. Due to their fairly close proximities, all three orbit around a common center of mass.

Some experts think two other stars, Polaris C and Polaris D, may be "gravitationally bound" to this trio, though they’re located a bit farther off.

Despite how strongly it shines, Polaris is only the 50th brightest star in the sky. Its luminosity fluctuates; right now, it’s in the midst of a particularly dazzling cycle. Today the star system looks up to 4.6 times brighter than it did in the past.

Polaris won't be the North Star for much longer (at least on the timescale of the universe). Because Earth’s axis wobbles over time, Polaris will lose its North Star status about 12,000 years from now when the more radiant Vega—which thousands of years ago was the North Star—reclaims its place. 

A Florida Brewery Created Edible Six-Pack Rings to Protect Marine Animals

For tiny scraps of plastic, six-pack rings can pose a huge threat to marine life. Small enough and ubiquitous enough that they’re easy to discard and forget about, the little plastic webs all too often make their way to the ocean, where animals can ingest or become trapped in them. In order to combat that problem, Florida-based Saltwater Brewery has created what they say is the world’s first fully biodegradable, compostable, edible six-pack rings.

The edible rings are made of barley and wheat and are, if not necessarily tasty, at least safe for animals and humans to ingest. Saltwater Brewery started packaging their beers with the edible six-pack rings in 2016. They charge slightly more for their brews to offset the cost of the rings' production. They hope that customers will be willing to pay a bit more for the environmentally friendly beers and are encouraging other companies to adopt the edible six-pack rings in order to lower manufacturing prices and save more animals.

As Saltwater Brewery president Chris Gove says in the video above: “We want to influence the big guys and kind of inspire them to also get on board.”

When Chuck Yeager Tweeted Details About His Historic, Sound Barrier-Breaking Flight

Seventy years ago today—on October 14, 1947—Charles Elwood Yeager became the first person to travel faster than the speed of sound. The Air Force pilot broke the sound barrier in an experimental X-1 rocket plane (nicknamed “Glamorous Glennis”) over a California dry lake at an altitude of 25,000 feet.

In 2015, the nonagenarian posted a few details on Twitter surrounding the anniversary of the achievement, giving amazing insight into the history-making flight.

For even more on the historic ride, check out the video below.


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