Epic Meteor Adventure and Ozone Mystery

SciShow explores two celestial mysteries: the origins of a meteorite that crashed into a house in California, and who’s releasing chemicals into the atmosphere that were banned more than 25 years ago?

Understanding ALS & SciShow News Takes the Ice Bucket Challenge

SciShow News explains the science behind ALS, the disease that has inspired millions to take the Ice Bucket Challenge. Learn what ALS is, what we do and don’t know about it, and watch SSN hosts take the challenge themselves!

What's the "DO NOT EAT" thing in packaged foods, what's in it and how does it work? Thanks!

It’s silica gel…an artifical form of silicon dioxide (the same stuff that makes up sand) that has tons of tiny pores that have affinities for water. Silica gel can absorb around 40% of its weight in water. It’s manufactured to be entirely dry and then placed in food or other products that manufacturers don’t want to get moist in humid climates (slightly moist chips are what we in the real world call “stale.”) Water would rather be in the silica matrix than the food matrix, so that’s where it goes, keeping the food nice and dry.

And if you’re wondering why you shouldn’t eat it…it’s just because it’s not technically food. It’s not dangerous though…it’s just fancy sand.

-Hank

Astronaut Weightlessness Training

SciShow Space takes you behind the scenes of astronaut training, to show how crew members and their equipment are tested in microgravity, all while never having to leave Earth.

Does Alcohol Kill Brain Cells?

Quick Questions explains what alcohol does — and doesn’t do — to your brain cells. Enjoy this episode responsibly!

What Causes Morning Sickness?

If you’ve ever been pregnant, or been around a pregnant lady, you know that the agony that is morning sickness — and it’s not just something that happens in the morning! SciShow explains the many theories about what causes it.

Dear sci show why heavy metals (Led, Mercury) are harmful to humans while lighter ones like iron and magnesium are beneficial?

"Heavy metals" is more of a colloquial term than a scientific one. There are lots of very heavy metals that aren’t dangerous at all. We wear gold and silver and platinum in our jewelry. Bismuth is all up in your PeptoBismol and most of the lanthanides and actinides are safe. Also, lots of the lighter metals (particularly sodium and lithium) while being great in certain chemical forms, in their pure forms will kill you extremely quickly (and violently.)

What it comes down to is simply whether the metal interferes with the normal functioning of your body. And we’ve got complicated bodily chemistries so it turns out that there are around a dozen metals that you don’t want to get in your body. At the same time, some of them, like zinc, are helpful it certain chemical configurations. A great example of how it’s not about the metal so much as the chemistry of the body…copper is safe for humans, but is extremely toxic to fish.

-Hank

The First Robot Swarm, and Evolution’s Misfit

Hank shares the nuts-and-bolts of the world’s first robot swarm, and explains what the creepy, cute and extinct animal known as Hallucigenia can teach us about evolution.

Why do different instruments (or voices) in the same note still sound different (a violin and a piano sound differently even if they're playing the same note)?

This is extremely weird and difficult to explain…which is why we’re lucky to have Vi Hart: https://www.youtube.com/watch?v=i_0DXxNeaQ0

-Hank

Stardust Discovery, and 2 Planetary Conjunctions

SciShow Space shares the latest developments from around the universe, including news about the first material ever collected from outside the solar system, and a backyard astronomers’ guide to two upcoming planetary conjunctions.