Go to https://brilliant.org/nutshell/ to dive deeper into these topics and more with a free 30-day trial + 20% off the premium subscription! This video was sponsored by Brilliant. Thanks a lot for the support! Glow up your space with posters that don’t just shine – they spark curiosity ✨ Get your own beautifully crafted space poster (and directly support kurzgesagt in the process!): https://shop.kgs.link/space Sources & further reading: https://sites.google.com/view/sources... Gravastars could change how we think about the universe. These cosmic objects solve black holes’ biggest problems without breaking physics. From their ultra-thin shell to their energy-filled core, gravastars are both elegant and terrifying. But what exactly are they?