1.5 billion years after the Big Bang, the Universe was still in chaos.
Except for this galaxy. https://www.syfy.com/syfywire/how-did-this-galaxy-emerge-from-the-chaos-just-15-billion-years-after-the-big-bang">https://www.syfy.com/syfywire/...
Except for this galaxy. https://www.syfy.com/syfywire/how-did-this-galaxy-emerge-from-the-chaos-just-15-billion-years-after-the-big-bang">https://www.syfy.com/syfywire/...
2/ Nicknamed the Wolfe Galaxy, it was already about as big as our Milky Way, a huge rotating disk of gas and stars! Astronomers are still trying to figure out how galaxies first assembled themselves, and this one is a monkey in the wrench of the traditional ideas.
3/ I mean, wow, try putting together a coherent object a hundred thousand light years across in the midst of all *this*.
4/ The old idea is that gas comes flying in due to gravity, piles up, heats up, cools off, then shapes itself into a galaxy. But that wouldn’t work for this galaxy. The disk would never be able to form in less than 5 billion years or so. This galaxy is < 1.5 billion years old!
5/ Somehow, it was able to sip a step and collect cooler gas, which is much more amenable to forming stars and larger structures. The question is how. Maybe a slow stream, or gently merging with smaller gas-rich galaxies? It’s not clear, and every idea has other problems, too.
6/ And the real corker is that the way this galaxy was found (details in my article) strongly imply there are LOTS more like it in the early Universe. So however it formed, it was probably a common method. But it’s still a mystery.
7/7 There’s still a lot to understand about how our modern, local cosmos came to be. The only way to know is to keep peering as far away as we can, into the past, and decipher what that young Universe is telling us. https://www.syfy.com/syfywire/how-did-this-galaxy-emerge-from-the-chaos-just-15-billion-years-after-the-big-bang">https://www.syfy.com/syfywire/...