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The Late Movies: Khan Academy

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Khan Academy provides free instructional videos (among many other things) for K-12 kids to learn about a variety of topics (the site currently boasts a library of over 2,600 videos!). You can read more about Khan or just dive into some awesome learning. Below, I've rounded up a few starter videos to give you a taste.

Khan Explains How it Works

A fun TED Talk. "First time I smiled doing a derivative!"

Banking 1

An "introduction to how banks make money and the value they (potentially) add to society."

Calculus: Introduction to Limits

Whoa.

Chemistry: Elements and Atoms

"How elements relate to atoms. The basics of how protons, electrons and neutrons make up an atom."

Computer Science: Introduction to Programs, Data Types, and Variables

Points to Khan for using Python, though we all know real men write in Assembler.

Astronomy: Scale of Earth and Sun

Just how big is the Earth? One nerd-jerk note from me: this video misuses the term "further." It should be "farther" when referring to distance.

Tell Your Khan Story

Do you use Khan Academy? Leave your thoughts and links to favorite videos and exercises in the comments.

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Johan Ordonez, Getty Images
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This Organization Wants Your Old Eclipse Glasses
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Johan Ordonez, Getty Images

On Monday, August 21, America hosted what may have been the most-viewed solar eclipse in history. While those of us in the United States are still processing the awesome sight, residents of South America and Asia are just starting to look forward to the next total eclipse in 2019—and anyone who still has their protective glasses on hand can help them prepare.

According to Gizmodo, Astronomers Without Borders is accepting donations of used eyewear following Monday’s event. Any glasses they collect will be redistributed to schools across Asia and South America where children can use them to view the world’s next total eclipse in safety.

Astronomers Without Borders is dedicated to making astronomy accessible to people around the world. For this most recent eclipse, they provided 100,000 free glasses to schools, youth community centers, and children's hospitals in the U.S. If you’re willing to contribute to their next effort, hold on to your specs for now—the group plans to the announce the address where you can send them in the near future. Donors who don't have the patience to wait for updates on the group's Facebook page can send glasses immediately to its corporate sponsor, Explore Scientific, at 1010 S. 48th Street, Springdale, Arizona 72762.

Not sure if your glasses are suitable for reuse? Here’s the criteria they should meet for sun-gazing.

[h/t Gizmodo]

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Health
Here's How to Tell If You Damaged Your Eyes Watching the Eclipse
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iStock

Amid the total solar eclipse craze, experts repeatedly warned spectators not to watch the rare phenomenon on August 21 with their naked eyes. But if you caught a peek sans glasses, pinhole projector, or protective filter, you may be wondering if your peepers were damaged. (After the sky show, "my eyes hurt" spiked as a Google search, so you’re not alone.)

While the sun doesn’t technically harm your eyes any more than usual during a solar eclipse, it can be easier to gaze at the glowing orb when the moon covers it. And looking directly at the sun—even briefly—can damage a spot in the retina called the fovea, which ensures clear central vision. This leads to a condition called solar retinopathy.

You won’t initially feel any pain if your eyes were damaged, as our retinas don’t have  pain receptors. But according to Live Science, symptoms of solar retinopathy can arise within hours (typically around 12 hours after sun exposure), and can include blurred or distorted vision, light sensitivity, a blind spot in one or both eyes, or changes in the way you see color (a condition called chromatopsia).

These symptoms can improve over several months to a year, but some people may experience lingering problems, like a small blind spot in their field of vision. Others may suffer permanent damage.

That said, if you only looked at the sun for a moment, you’re probably fine. “If you look at it for a second or two, nothing will happen," Jacob Chung, chief of ophthalmology at New Jersey's Englewood Hospital, told USA TODAY. "Five seconds, I'm not sure, but 10 seconds is probably too long, and 20 seconds is definitely too long."

However, if you did gaze at the sun for too long and you believe you may have damaged your eyes, get a professional opinion, stat. “Seeing an optometrist is faster than getting to see an ophthalmologist,” Ralph Chou, a professor emeritus of optometry and vision science at the University of Waterloo, in Ontario, Canada, told NPR. “If there is damage, the optometrist would refer the individual to the ophthalmologist for further assessment and management in any case.”

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