defranco:

QnA Stuffs, Nation! (X)

OK, Phil…SciShow is here for you. Technically, we can’t see water either, unless we’re looking through a bunch of it. But your average glass of water, you aren’t seeing the water in there, you’re seeing two effects:

1. The surface where the water and the air meet (or the water and the glass). That surface can reflect light. Fish can see the surface of the water as well (it looks different from below, but it’s still visible.) But you can’t really see the water. Also, when water is on a person and they’re all shiny, that’s just because the water on them is all surface and you’re seeing all that surface.

2. The difference in the index of refraction between water and air. Light moves at different angles through different materials. So when you see water, especially in a glass, you’ll see it bending the light differently than air bends light. Fish would not see this, in the same way we don’t notice the index of refraction of air.

However, they DO see AIR in the same way WE see WATER! They would see the surface between the two and they would notice the difference in refraction between the two substances and note that “air” is a thing that they can see just like we imagine water as something we can see. Bubbles, y’know…

Now, there are two other things you might think. One, that you can see water because there’s stuff in it…but that’s just seeing the stuff…like you wouldn’t say you could see air just because there’s smoke or a cloud…you’re just seeing stuff IN the air. 

And last…water actually does absorb light, so if you look through a lot of it, you /can/ see it. However, this is also true of air, it’s just that air absorbs less light (much less, if there’s no water vapor in it.) So, in the same way that we can see air if we’re looking through enough of it (a very far away mountain will appear diluted and blue) fish would also be able to see water.

humanoidhistory:

October 1, 1965 — Gemini 6 astronauts Tom Stafford and Wally Schirra photographed during a suiting-up training exercise at Cape Canaveral, Florida. (NASA)

humanoidhistory:

October 1, 1965 — Gemini 6 astronauts Tom Stafford and Wally Schirra photographed during a suiting-up training exercise at Cape Canaveral, Florida. (NASA)

fuckyeahfluiddynamics:

This surrealistic timelapse doesn’t show an ocean in the sky. These are undulatus asperatus clouds rolling over Lincoln, Nebraska. Also known simply as asperatus, this cloud formation has been proposed as but not yet recognized as a distinctive cloud type. Their speed is much slower than shown in the animation, but the wave-like motion is accurate and is the source of the cloud’s name, which comes from the Latin word aspero, meaning to make rough. Though they appear stormy, asperatus clouds do not usually produce storms. They form under conditions similar to those of mammatus clouds, but wind shear at the cloud level causes the undulations to form. (Maybe some Kelvin-Helmholtz instabilities going on there?) You can check many more images of asperatus clouds at the Cloud Appreciation Society’s gallery. (Image credit: A. Schueth, source video; submitted by leftcoastjunkies)

fuckyeahfluiddynamics:

This surrealistic timelapse doesn’t show an ocean in the sky. These are undulatus asperatus clouds rolling over Lincoln, Nebraska. Also known simply as asperatus, this cloud formation has been proposed as but not yet recognized as a distinctive cloud type. Their speed is much slower than shown in the animation, but the wave-like motion is accurate and is the source of the cloud’s name, which comes from the Latin word aspero, meaning to make rough. Though they appear stormy, asperatus clouds do not usually produce storms. They form under conditions similar to those of mammatus clouds, but wind shear at the cloud level causes the undulations to form. (Maybe some Kelvin-Helmholtz instabilities going on there?) You can check many more images of asperatus clouds at the Cloud Appreciation Society’s gallery. (Image credit: A. Schueth, source video; submitted by leftcoastjunkies)

So Hank, what's the deal with Pluto right now? Is it a planet or not?

edwardspoonhands:

Pluto is not a planet. The IAU (in my book) gets to decide what the definition of a planet is because there has to be a definition and they are by far the most qualified body to define it. 

Pluto does not meet that definition, and thus should not be considered a planet. I agree with their definition, but even if I didn’t I would submit to it because I am not an expert. 

Recently, three people sat in a room and argued about whether pluto was a planet. The audience then voted…and they voted that Pluto was a planet. That, of course, means nothing. If you want random groups of people to define scientific terms…it’s going to be hard to get any actual science done. 

Some context regarding the recent debate for you.

mrgneiss:

image

This idea got stuck in my head while watching the tick episode and I just had to see if I could make it a thing..I tried my best!! :-D

https://www.youtube.com/watch?v=m9H3lnRaiXA

What Would Happen If the Planets Lined Up?

Planetary alignments: They’re the favorite astronomical scenario of kooks, con artists, and Hollywood producers everywhere. But has it ever happened? And what would it do to Earth if it did? 

corfy:

That was quick. Seems like only a couple days ago I told SciShow I wanted to spend my banked Subbable cash by sponsoring a graphic. And here it is in the “The Science of Wildfires" video.

Thanks for the support, my friend!

corfy:

That was quick. Seems like only a couple days ago I told SciShow I wanted to spend my banked Subbable cash by sponsoring a graphic. And here it is in the “The Science of Wildfires" video.

Thanks for the support, my friend!

Does My Voice Really Sound Like That?

Take it from an expert: It’s weird to hear how your voice really sounds. But why does it sound different to you than everyone else. Hank explains — in a deep, resonant voice.

jtotheizzoe:

NEW VIDEO!

Bats: Wonders of the Night

In this week’s It’s Okay To Be Smart you’ll learn all about some BAT-ass flying mammals. 

I live in Austin, TX, a city known for breakfast tacos, cowboy hipsters, live music, and BATS. Lots of bats. Yet, even after living in this city for years, I had no idea just how many bats called Central Texas home. That is, until I shot this video.

Our backdrop for this episode, Bracken Cave near San Antonio, TX, is a very special place. That cave is home the largest congregation of mammals on Earth, 20+ million Mexican free-tailed bats. In some areas of the cave, 200+ are hanging in a single square foot! At sunset, when they journey out to find dinner… well, it’s one of the most amazing sights I’ve ever seen (and heard). Their emergence lasts hours, flowing overhead like a river of wings, rushing by with the sound of a fluttering waterfall.

The bats that live here can eat as many as 100 tons of insects in a single night! Exactly how they hunt is even cooler, but you’ll have to watch the video to find out more.

You’ll also learn what bats eat, why they might be the most advanced flying hunters in nature, the incredible impact they have on ecosystems, and how we are threatening their future with disease and habitat loss. Oh, and poop. You’ll learn about bat poop.

Special thanks to Bat Conservation International for their help making this video. They own the land around Bracken Cave, in order to protect this natural treasure for the future. Check out their website to learn how you can help protect these amazing animals.

If you like the videos we’re making, please consider subscribing on YouTube, and share this one with your bat-loving friends :)

SciShow shirts for sale! We haven’t released any new SciShow merch in a very, very long time. But now, you can get this fancy schmancy sleek and super cool SciShow logo shirt. It’s printed on a nice, soft black tee. These are available for preorder now and will ship some time near the end of October.

SciShow shirts for sale! We haven’t released any new SciShow merch in a very, very long time. But now, you can get this fancy schmancy sleek and super cool SciShow logo shirt. It’s printed on a nice, soft black tee. These are available for preorder now and will ship some time near the end of October.