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How is glass made?

Glass bottles being made at Anchor Glass in Shakopee, Minn. (Molly Bloom | MPR News)
Glass bottles being made at Anchor Glass in Shakopee, Minn. (Molly Bloom | MPR News)

The process that turns sand into glass is very cool – or rather, we should say very hot. Very, very, very hot as it turns out. Humans have been turning minerals from the earth’s crust into glass for 3,500 years. Find out how it’s done and how it’s evolved – from blowing glass by hand to a factory that makes hundreds of glass bottles every minute. Plus: The mystery sound!

Allergy attack: How our bodies can overreact

Scanning Electron Microscopic image of pollen grains from sunflower, morning glory, prairie hollyhock, oriental lily, evening primrose, and castor bean. (Courtesy of NASA)
Scanning Electron Microscopic image of pollen grains from sunflower, morning glory, prairie hollyhock, oriental lily, evening primrose, and castor bean. (Courtesy of NASA)

Pollen, peanuts, dust mites. These things aren’t poisonous – so why do some people’s bodies act like they are? In this episode, we’ll find out what happens during an allergic reaction and hear about new treatments.

Mosquitoes: What are they good for?

A mosquito feeding on the finger of medical entomologist Lyric Bartholomay. (Image courtesy of Lyric Bartholomay)
A mosquito feeding on the finger of medical entomologist Lyric Bartholomay. (Image courtesy of Lyric Bartholomay)

How and why do mosquitoes suck our blood? Why do their bites itch ALL the time? Why do some people get bitten more than others? And do these pesky and possibly dangerous insects serve any kind of useful purpose?

How do airplanes fly?

(Courtesy of NASA)
(Courtesy of NASA)

How do planes stay in the air? And how did humans figure out that it wasn’t enough to just strap wings to our arms and flap them like birds?

Big universe, big questions

This huge Hubble Space Telescope mosaic, spanning a width of 600 light-years, shows a star factory of more the 800,000 stars being born. The stars are embedded inside the Tarantula Nebula. (Photo credit: NASA, ESA, and E. Sabbi/STScI)
This huge Hubble Space Telescope mosaic, spanning a width of 600 light-years, shows a star factory of more the 800,000 stars being born. The stars are embedded inside the Tarantula Nebula. (Photo credit: NASA, ESA, and E. Sabbi/STScI)

Have you ever wondered about what’s beyond the edge of the universe? Or maybe a better question: is there even an edge of the universe? And what does it mean that the universe is expanding? Nine-year-old Thea talks with astrophysicist Katie Mack to find answers to her many questions about the universe.

The how’s and why’s of hair

A microscopic view of hair. (Courtesy of Sandy Koch)
A microscopic view of hair. (Courtesy of Sandy Koch)

Why do humans have hair and not fur? How does hair grow? Why does it turn gray? How does hair become curly or straight? Black, brown, blonde or red?

Why don’t carnivores need to eat their vegetables?

(Mehgan Murphy |Smithsonian's National Zoo)
(Mehgan Murphy |Smithsonian's National Zoo)

We’re back with new episodes! Carnivores are animals that only eat other animals – so how do they get the vitamins, minerals and fiber that we humans get from eating plants? We take a trip to a salad bar with some animal pals to find out.

How do you catch a cold? (Encore)

Image of a rhinovirus from Jean-Yves Sgro of the University of Wisconsin-Madison.
Image of a rhinovirus from Jean-Yves Sgro of the University of Wisconsin-Madison.

We’ve been catching colds for millennia – but it wasn’t until fairly recently that we actually understood how and why we get sneezy, coughy, and achy. In this episode, we find out more about the common cold: Does standing outside in the cold actually make it easier to get sick? Is there a cure that […]

“I Am the Universe” by Jasper Nordin

Aliens are awesome. Some are so huge, 50,000 beings could fit on their pinkie fingertips. Some are so tiny, several trillion of them could live on the head of a pin. There is a theory, however, that the Universe itself is a massive alien; the stars and planets are merely pores on its skin. In […]