This Mind-Bending Optical Illusion Can Be Viewed Three Different Ways

The Illusion Contest, Youtube

The Illusion Contest, Youtube

Some optical illusions get more confusing the longer you look at them. Take the triply ambiguous object illusion as an example: At first glance, it looks like a fairly straightforward 3D object, but as the video below shows, what you see changes entirely depending on which angle you view it from.

The secret behind the "3D" object in this illusion is that it isn't really three-dimensional at all. It's a flat piece of paper with shaded, geometric shapes sketched onto it, giving it the appearance of depth. This means that shapes that seem to be at the "top" of the object appear at the bottom if you turn the paper 180 degrees. The flag pin, which stays in the same spot no matter how you view the illusion, is the only element that isn't two-dimensional.

The triply ambiguous object illusion from Kokichi Sugihara received first place in the 2018 Best Illusion of the Year contest, an annual competition held by the Neural Correlate Society. You can check out more award-winning optical illusions here.

6 Protective Mask Bundles You Can Get On Sale

pinkomelet/iStock via Getty Images Plus
pinkomelet/iStock via Getty Images Plus

Daily life has changed immeasurably since the onset of COVID-19, and one of the ways people have had to adjust is by wearing protective masks out in public places, including in parks and supermarkets. These are an essential part of fighting the spread of the virus, and there are plenty of options for you depending on what you need, whether your situation calls for disposable masks to run quick errands or the more long-lasting KN95 model if you're going to work. Check out some options you can pick up on sale right now.

1. Cotton Face Masks; $20 for 4

Protective Masks with Patterns.
Triple7Deals

This four-pack of washable cotton face masks comes in tie-dye, kids patterns, and even a series of mustache patterns, so you can do your part to mask germs without also covering your personality.

Buy it: $20 for four (50 percent off)

2. CE- and FDA-Approved KN95 Mask; $50 for 10

A woman putting on a protective mask.
BetaFresh

You’ve likely heard about the N95 face mask and its important role in keeping frontline workers safe. Now, you can get a similar model for yourself. The KN95 has a dual particle layer, which can protect you from 99 percent of particles in the air and those around you from 70 percent of the particles you exhale. Nose clips and ear straps provide security and comfort, giving you some much-needed peace of mind.

Buy it: $50 for 10 (50 percent off)

3. Three-Ply Masks; $13 for 10

Woman wearing a three-ply protective mask.
XtremeTime

These three-ply, non-medical, non-woven face masks provide a moisture-proof layer against your face with strong filtering to keep you and everyone around you safe. The middle layer filters non-oily particles in the air and the outer layer works to block visible objects, like droplets.

Buy it: $13 for 10 (50 percent off)

4. Disposable masks; $44 for 50

A batch of disposable masks.
Odash, Inc.

If the thought of reusing the same mask from one outing to the next makes you feel uneasy, there’s a disposable option that doesn’t compromise quality; in fact, it uses the same three-layered and non-woven protection as other masks to keep you safe from airborne particles. Each mask in this pack of 50 can be worn safely for up to 10 hours. Once you're done, safely dispose of it and start your next outing with a new one.

Buy it: $44 for 50 (41 percent off)

5. Polyester Masks; $22 for 5

Polyester protective masks.
Triple7Deals

These masks are a blend of 95 percent polyester and 5 percent spandex, and they work to block particles from spreading in the air. And because they're easily compressed, they can travel with you in your bag or pocket, whether you're going to work or out to the store.

Buy it: $22 for five (56 percent off)

6. Mask Protector Cases; $15 for 3

Protective mask case.
Triple7Deals

You're going to need to have a stash of masks on hand for the foreseeable future, so it's a good idea to protect the ones you’ve got. This face mask protector case is waterproof and dust-proof to preserve your mask as long as possible.

Buy it: $15 for three (50 percent off)

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How to Brew Your Own Fluorescent Beer at Home

The Odin
The Odin

If you're one of the many people who made their own sourdough starter in quarantine, you already know yeast is a living thing. That means its biological makeup can be tweaked using genetic engineering. As Gizmodo reports, that's exactly what a former NASA biologist has done to create his new fluorescent yeast kits.

A few years ago, Josiah Zayner left his job as a synthetic biologist for NASA to found The Odin, a company that lets anyone experiment with genetic science at home. His recently launched yeast kit accomplishes this in an eye-catching way. Thanks to a fluorescent protein from jellyfish, yeast that's been genetically modified with the kit glows green under a black or blue light.

Despite looking like a prop from a sci-fi film, the yeast is still yeast. That means it can be used in home-brewing projects if you want to take the science experiment a step further. According to Eater, yeast made with the kit ferments and fluoresces when added to honey and water. If you brew a batch of beer with the right amount of yeast, the final product will emit an otherworldly glow when viewed under a blacklight. The kit hasn't been FDA approved, but the company states the materials are nontoxic and nonallergenic, and beer made with it will still taste like beer.

You can purchase a fluorescent yeast kit from The Odin's online shop for $169. If you're looking for more ways to experiment with genetic technology at home, the company also sells kits that let you play with frog and bacteria DNA.

[h/t Gizmodo]