The history of the Universe, as far back as we can see using a variety of tools and telescopes, out to the maximum present depth of SDSS. We are now up to SDSS-16, which can go all the way back to just ~3 billion years after the Big Bang, mapping out more than 2 million galaxies in the process. (SLOAN DIGITAL SKY SURVEY (SDSS))

Record-Breaking 3D Map Of The Universe Reveals Some Big Surprises

How quickly is it expanding today, and how does that expansion rate change over time?

Ethan Siegel
Jul 28, 2020 · 9 min read

What is the Universe made of? How quickly is it expanding today, and how does that expansion rate change over time? If we could know the answers to these questions, we’d understand both the past history and…