File talk:Observable Universe Logarithmic Map (horizontal layout english annotations).png

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I have an issue with referring to this as a logarithmic map. In a logarithmic map, moving a particular distance (to the right, in this case) should produce the same multiplier. That is, if moving right 1 cm doubles the distance, then moving right another cm should always double it.

However, look at the distance from Earth to Moon. This real distance is about 1.3 light-seconds. Then move from the moon to the Sun. The distance from Earth to the Sun is 499 light-seconds. So we're saying the linear distance on the map from Moon to Sun is a little less than a X400 multiplier. So each time we move that amount on the map should be roughly a X400 multiplier. However, if you move out that much beyond the Sun, you are right about at Saturn, implying that Saturn would be about 400X farther from Earth than the Sun is. Saturn is actually about 4600 light-seconds from Earth, or not even 10X the Earth-Sun distance.

Moving out to the center of the Milky Way from the Sun is roughly 4 of our X400 spans, which would imply that the Milky Way is 400,000 light-years away. (1.58e-5 X 400^4) This is not disastrously far from actual value of 25,800 light-years -- almost within an order of magnitude.

The linear distance from the center of the Milky Way to the edge of the universe is about twice the 400X multiplier distance, so you'd expect it to be 25,800 X 400^2 in light years, or 4 billion light-years. The actual value is about 93 billion light-years, so it's nearly within an order of magnitude, but wrong in the other direction.

So I guess that my big complaint is the section from the Sun to the edge of the Solar System -- this part is way off. Otherwise, it's not that bad, which means it's a lot closer than I had originally thought it was when I started writing this note. — 以上未签名的留言是由该用户加入的: AnotherCuriousOne (留言 • 贡献) 14:36, 17 September 2021 (UTC)[回复]