Happy New Year!
I encountered the above diagram in the book To Infinity and Beyond: A Journey of Cosmic Discovery by Neil deGrasse Tyson and Lindsey Nix Walker. The caption for the diagram was as follows:
In this radial logarithmic conception of the observable universe, our solar system sits at the center. Expanding outward are the inner and outer planets, Kuiper belt, Oort cloud, Alpha Centauri, Perseus arm, Milky Way galaxy, Andromeda galaxy, nearby galaxies, cosmic web, and cosmic microwave radiation, with the Big Bang at the outer edge.
The diagram is by Pablo Carlos Budassi, who creates a lot of cosmic-themed art of this nature.
More recently I saw the Budassi diagram below, in an online article by Ethan Siegel titled “Busting the top 5 myths about the Big Bang”.
Its caption reads,
Artist’s logarithmic scale conception of the observable universe. Note that we’re limited in how far we can see back by the amount of time that’s occurred since the hot Big Bang: 13.8 billion years, or (including the expansion of the Universe) 46 billion light years. Anyone living in our Universe, at any location, would see almost exactly the same thing from their vantage point.
Here is yet another similar artwork by Budassi.
All these are log scaled, which means that as you move out from the center, each subsequent centimeter of distance represents some multiple of the distance in the previous centimeter.
Now, what first caught my eye about the diagram in To Infinity and Beyond was that the sun was at the center of the diagram. The sun is at the center of all these diagrams. But why? These works of art are designed to compress the entire observable universe, the universe that we see, into a finite space. And as the caption says, “Anyone living in our Universe, at any location, would see almost exactly the same thing from their vantage point.” Well, what is our vantage point? Our vantage point is the Earth.
So why isn’t the Earth at the center of these diagrams?
Budassi has made art work that does show our vantage point properly, like the one below. Why not use one like that?
Perhaps it’s because we have a certain association with an Earth-centric or geocentric view of the universe. I mean, after all, since we know today that the universe is primarily composed of dark matter and dark energy, things we do not find on Earth (at least not yet), then if we properly put the Earth at the center of these diagrams, we would see a diagram of a spherical universe, with the Earth at the center, with the universe composed primarily of some mysterious substance (we know not what). Perhaps that’s just a little too Aristotelian for us today.
I hope your outlook on the New Year comes from a good vantage point!
