Here’s one way to try to get a handle on just how immense our little corner of the cosmos really is, as described by Prof. Jay M. Pasachoff of Williams College-Hopkins Observatory in Williamstown, Mass. in his book Astronomy: From the Earth to the Universe (Saunders College Publishing 1983). I’ve paraphrased a bit:
Imagine the Solar System is scaled down and placed on a map of the United States. The Sun is a hot ball of gas taking up all of Rockefeller Center, a kilometer wide, in the heart of Manhattan in New York City. Mercury, then, is a sphere four meters wide in mid-Long Island. Venus is a ball ten meters around, about one and a half times farther away. The Earth is only slightly bigger, located near Trenton, N.J., while Mars is half that size, five meters wide, located past Philadelphia, Pa.
Jupiter, the next planet out from the Sun, is a hundred meters across (about the size of a baseball stadium), past Pittsburgh on the Ohio border. Saturn, with its rings, is a little larger than Jupiter, and is beyond Cincinnati, toward the Indiana state line. Uranus and Neptune are each about thirty meters across, about the size of a baseball infield, and are near Topeka, Kans. and Santa Fe, N.M., respectively. Pluto, about the size of Mercury, is near Los Angeles, forty times the distance of the Earth from the Sun.
This is an awesome scale solar system model that you can do yourself, and it does an absolutely fantastic job of conveying the size of the solar system. I can’t recommend it highly enough.
Professor Pasachoff’s scale is significantly off in a couple of places. Pluto is not “about the size of Mercury.” It’s less than half the diameter (about 5000 km versus about 2200 km).
Actually, let’s do the math. Assuming the sun in this scale model is 1000m in diameter, here are our planetary diameters:[ul][li]Mercury = 3.5 meters[]Venus = 8.7 meters []Earth = 9.2 meters []Mars = 4.9 meters []Jupiter = 120.7 meters []Saturn = 86.6 meters, 168.9 meters if rings are included []Uranus = 36.7 meters []Neptune = 35.5 meters []Pluto = 1.7 meters[/ul]I don’t know where he’s getting his diameter for Saturn. And as mentioned above, his diameter for Pluto is way off. [/li]
And here are the distances from the center of the sun (calculated using the orbital apheliion, and still assuming the sun’s diameter is 1000 meters):[ul][]Mercury = 50 km[]Venus = 78 km []Earth = 109 km []Mars = 179 km []Jupiter = 586 km []Saturn = 1087 km []Uranus = 2158 km []Neptune = 3271 km [*]Pluto = 5298 km[/ul]It looks like he’s fairly accurate on these.
