There are hundreds of billions of alien worlds in the Milky Way galaxy. And scientists have already discovered and confirmed over 5,000 of them. Small rocky worlds like Kepler-37 b are a pretty rare find. Because they're so tiny, they're more difficult to spot. But scientists have still managed to confirm about 200 of those worlds. 00:00 Exoplanets 01:37 KOI-55 b 02:26 GJ 1132 b 03:28 Kepler-452 b 08:09 HD 100546 b Questions or concerns? Contact us at underknown.com/contact Interested in sponsoring our episodes or collaborating? Email us: inquiries@underknown.com Get our 100 best episodes in one mind-blowing book: bit.ly/ytc-the-what-if-100-book Join this channel to get access to perks: youtube.com/channel/UCphTF9wHwhCt-BzIq-s4V-g/join Get a Cameo by Peter: cameo.com/whatifguy Check out our other channels: How to Survive: bit.ly/how-to-survive-show Aperture: bit.ly/aperture-show Your Body On: bit.ly/your-body-on-sho...