Is there a convenient listing of the timeframe of cosmic events?
I have a poor sense of when we’re talking hours, years, decades, millennia, MA, GA. Might make for a really cool static website project.
Same with geologic events, too!
I have a poor sense of when we’re talking hours, years, decades, millennia, MA, GA. Might make for a really cool static website project.
Same with geologic events, too!
E.g., "Within a few seconds of the collapse process, a substantial fraction of the matter in the white dwarf undergoes nuclear fusion, releasing enough energy (1–2×10^44 J) to unbind the star in a supernova."
https://www.historytimeline.com/timeline/geo-time-scale/
DM if interested in the datasets.
you're in good company. most cosmological "dates" are not precise. for example, the age of the universe is suspected to be about 13.7 billion years +/- 20 million years. That's a really big +/- in years, but just 0.2% tolerance. the size of milky way is estimated at 26.8 ± 1.1 kiloparsecs. again, that's a lot of miles/kilometers of a range. it's not like they can run out and "pull tape" to take that measurement.
it's one of my favorite quirks of astronomy. of course even the tolerances/variances are going to be astronomically large.
1. The massive, central black hole did not come from a supernova. There are no stars anything like that big.
2. Even if there were a huge central mass and it collapsed, that doesn't actually change the mass distribution as far as the rest of the galaxy is concerned. There is very little change to propagate. The existence of the huge central mass would have already "arranged" the galaxy.
3. Galaxies spiral with curved arms due to their own rotation, not due to the universe's rotation. If the universe were rotating like a disk (and that was causing the spiral of galaxies), then you would expect the spin of galaxies to all be aligned. And they aren't; not at all.