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NASA via Wikimedia Commons // Public Domain

How Do Astronauts Get Drinking Water on the ISS?

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NASA via Wikimedia Commons // Public Domain

Transporting anything to the space station is extremely expensive—launching a SpaceX rocket costs more than $1800 per pound. And you know what’s really heavy? Water. 

Tanks of H20 can't be constantly shipped up to the International Space Station, so the station has a complex water system that squeezes every last drop of available, drinkable liquid out of the environment. That leaves astronauts drinking a filtered mixture that includes recycled shower water, old astronaut sweat, and pee. The station also keeps about 530 gallons of water in reserve in case of an emergency. 

The NASA water systems on the ISS collect moisture from breath and sweat, urine from people and research animals, and runoff from sinks and showers to keep the station hydrated. “It tastes like bottled water, as long as you can psychologically get past the point that it’s recycled urine and condensate that comes out of the air,” Layne Carter, who manages the ISS water system from the Marshall Flight Center in Alabama, told Bloomberg Businessweek

However, not all the ISS astronauts drink recycled urine. The ISS is split into two sections, one run by Russia, and one by the United States, and they have two different water systems. The U.S. system collects condensate, runoff, and urine to create about 3.6 gallons of drinkable water per day. However, the Russian astronauts drink water processed from only shower runoff and condensate, skipping the urine (producing slightly less than that 3.6 gallons). Occasionally, the NASA astronauts will go over to the Russian side of the ISS and grab the Russian supplies of urine to process it themselves. No need to waste potential water supplies! 

In addition, the two sides of the ISS disinfect their water two different ways. Since 1981, NASA has been using iodine to disinfect water, a process that requires the water to be filtered since too much iodine can cause thyroid issues. Russia has been using silver to disinfect its water since the launch of the Mir station by the Soviet Union in 1986. 

[h/t: Bloomberg Businessweek]

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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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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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