View source for Intuitively understanding the size of Earth

If you build a minute model of the Earth with the diameter diameter equivalent to halve the width of a soccer field (~25m), <br>
then a model soccer field on that model Earth would have a with of approximately half a human hair (~0.05mm). Or a thin one.

It's the same ratio!
* 12,736km / 25m = ~ 500,000
* 25m / 0.05mm = ~ 500,000
See?

== How this relates to [[Intuitively understanding the size of an atom|the comparison for gaining a direct true intuition for the size of atoms]] ==

Interestingly the exact same factor that perhaps can suffice to make [[the size of atoms|a true intuitive understanding of the size of atoms]] possible, <br>
the factor of 500.000, also may make possible ''a true intuitive understanding of the size of Earth. <br>

== Bigger sizes fundamentally not directly intuitively comprehensible ==

Any sizes much beyond the size of the Earth are hopelessly beyond true direct intuitive comprehensibility.
* For interplanetary distances spaceship travel times can give a bit of a hint but that is far from a true direct intuitive comprehension.
* For interplanetary distances only relative size comparisons to something of a size already beyond direct everyday experience are possible. 
* For interstellar distances even that works barely. Stars are brutally far apart in terms of say our suns diameter. Much much much more so than planets are apart in terms of their diameter.

=== Relative comparison for stars (not at all sufficient for a direct true intuition) ===

'''Sun and currently nearest star:'''
* '''Sun''' 695508km / 5,000,000,000,000 = '''~0.1mm (hair diameter)'''
<small>Distance to proxima centauri (currently nearest star) 4,2465LJ* 9.46*10^12km/LJ = ~40*10^12km </small> <br>
<small>Distance to Neptune ~30AE*~150Gm/AE = ~ 4.5Tm </small>

* '''Distance to Neptune:''' ~ 4.5Tm / 5,000,000,000,000 = '''~1m'''
* '''Distance to proxima centauri:''' ~40*10^12km / 5,000,000,000,000 = '''~8km'''

'''One of the biggest stars in "reasonable" interstellar distance (same scale):'''
* '''Distance to Betelgeuse''' is ~100x farther than to proxima centauri. Scaled down hair-diameter-sized sun that makes '''800km'''
* '''Diameter of Betelgeuse''' is ~1000x the diameter of the sun. Scaled down hair-diameter-sized sun that makes '''10cm''' <br> These supergiant stars are often so big and dilute that they are basically a "hot vacuum".

== Related ==

* [[Intuitively understanding the size of an atom]]
* [[Magnification wonderworld]]