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What's a galactic tick (and why are we celebrating it today?)

Courtesy Joel Tonyan
/
Flickr http://j.mp/1SPGCl0

225 million years.

That's the amount of time it takes Earth -- and our Solar System -- to travel around the Milky Way Galaxy's galactic center.

We may not definitely will not live to see an entire orbit. But today we're celebrating progress. Specifically, we're celebrating "National Galactic Tick Day."

What's a galactic tick?

It's one centi-arcsecond of a rotation around the Milky Way's galactic center.

In layman's terms, we're celebrating the tiniest fraction of progress in our rotation, which happens every 1.7361 years according to Galactic Tick Day's website. The holiday has been celebrated every time a tick occurs since the telescope was patented. 

The holiday's founder is Davide Sneider, who will admit "it sounds silly on the surface." However, he says there are reasons to celebrate.

Sneider says the holiday first acts as a learning experience to better understand astronomical motions. He says it's also a larger celebration of science's ability to teach us information like a galactic tick. Third, he says, reflecting on the large rotations and forces around us can prove interesting to mediate on. 

"Some people find it crushingly depressing, " Sneider says, who adds that others use it to understand we’re "all in this together as a planetary society."  

Sneider adds that there's no official way to celebrate, but some people celebrated in part by taking to Twitter and informing people about the holiday. 

For more information on galactic tick day listen to our Stateside interview with Sneider below:

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