Mesmerizing Visualization of the Moon's Phases in 2013

This mesmerizing animation, released by NASA, shows the phases of the Moon throughout the entirety of 2013, which are caused by the changing angle of the Sun as the Moon orbits the Earth. According to NASA, "Elevation measurements by the Lunar Orbiter Laser Altimeter (LOLA) aboard the Lunar Reconnaissance Orbiter (LRO) make it possible to simulate shadows on the Moon's surface with unprecedented accuracy and detail."

Other graphics in the visualization show the Moon's orbit position, subsolar and subearth points, distance from the Earth, and more. You'll also see the Moon's libration. "Because of the tilt and shape of its orbit, we see the Moon from slightly different angles over the course of a month," the site for the visualization explains. "When a month is compressed into 24 seconds, as it is in this animation, our changing view of the Moon makes it look like it's wobbling. This wobble is called libration."

Each frame represents one hour; you can check out the visualization frame-by-frame—and enter specific dates or hours to see what the Moon looks like—here.

Peaceful, right?

And now, something decidedly not peaceful (thought definitely still cool): This video of two huge eruptions on the Sun, which occurred on November 16 within 4 hours of each other.

Thankfully, those flares weren't directed toward Earth.

The Queen of Code: Remembering Grace Hopper
By Lynn Gilbert, CC BY-SA 4.0, Wikimedia Commons

Grace Hopper was a computing pioneer. She coined the term "computer bug" after finding a moth stuck inside Harvard's Mark II computer in 1947 (which in turn led to the term "debug," meaning solving problems in computer code). She did the foundational work that led to the COBOL programming language, used in mission-critical computing systems for decades (including today). She worked in World War II using very early computers to help end the war. When she retired from the U.S. Navy at age 79, she was the oldest active-duty commissioned officer in the service. Hopper, who was born on this day in 1906, is a hero of computing and a brilliant role model, but not many people know her story.

In this short documentary from FiveThirtyEight, directed by Gillian Jacobs, we learned about Grace Hopper from several biographers, archival photographs, and footage of her speaking in her later years. If you've never heard of Grace Hopper, or you're even vaguely interested in the history of computing or women in computing, this is a must-watch:

Why Are Glaciers Blue?

The bright azure blue sported by many glaciers is one of nature's most stunning hues. But how does it happen, when the snow we see is usually white? As Joe Hanson of It's Okay to Be Smart explains in the video below, the snow and ice we see mostly looks white, cloudy, or clear because all of the visible light striking its surface is reflected back to us. But glaciers have a totally different structure—their many layers of tightly compressed snow means light has to travel much further, and is scattered many times throughout the depths. As the light bounces around, the light at the red and yellow end of the spectrum gets absorbed thanks to the vibrations of the water molecules inside the ice, leaving only blue and green light behind. For the details of exactly why that happens, check out Hanson's trip to Alaska's beautiful (and endangered) Mendenhall Glacier below.

[h/t The Kid Should See This]


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