A Lesson In Scale

A few days ago, my twin sons were preparing a project for their Awana Truth & Training club. The project involved making a "model of the solar system" and was to include Psalms 19:1:

"The heavens declare the glory of God,and the sky above proclaims his handiwork"

Once they had completed their own projects, I thought it would be fun to do a kind of "family" version. So, I identified a section of wall about 10 feet in length and drew a horizontal line about 3.5 feet off the ground. I labeled the left end of the line "the Sun" and drew a pretty big semi-circle - probably with a radius of 6-8 inches.
I took a book we had on the solar system and determined that Neptune, at 30 AU, would determine the scale. Given about 100 inches to work with, I decide to make my scale 3"=1AU. So, we put a dot on our line for each planet:

• 1.2" (0.4 AU) - Mercury
• 2.1" (0.7 AU) - Venus
• 3.0" (1.0 AU) - Earth
• 4.5" (1.5 AU) - Mars
• 15.6" (5.2 AU) - Jupiter (quite a gap there!)
• 28.5" (9.5 AU) - Saturn
• 58.8" (19.6 AU) - Uranus
• 90" (30 AU) - Neptune

Ok, so after plotting these 'dots' on my orbital plane, I decided we should give a sense of scale to these planets. So, at a scale of 1"=50,000,000km, I determined the size of the circle I would need to draw for Jupiter, the largest planet.

0.00285 inches

That's the diameter of Jupiter on my wall. Not even 3 one-thousandths of an inch. Wow. Ok, so now I'm doubting my math, because I just sort of assumed that I could at least SEE Jupiter in my model. I mean, the pencil dot I'd placed on my line was perhaps an order of magnitude or two in size greater than the 0.00285 inches it should have been. Not just that, the line itself was probably an order of magnitude too big.

So, the next logical question is. . .how big is the Sun on this scale? I got out my trusty calculator. . .

0.02784 inches

Not even three HUNDREDTHS of an inch? Remember - I'd drawn my "model" sun with a diameter of maybe EIGHT inches - 287x too big!! The dot I'd placed for the Earth was probably only half that size! At this scale, the solar system has a radius of nearly 10 feet, but you can't actually SEE any of the planets to scale! You can barely even see the Sun itself!!! And we're only talking about OUR solar system? Neptune, after all, is only 30 AU from the Sun! Alpha Centauri, our closest neighbor, is 277,600 AU. Or roughly 41,500,000,000,000km. On my scale, I'd have to put Alpha Centauri 830,000 inches away. That's 69,167 feet. That's 13 MILES away.

So what does all of this mean? In his book Taking Back Astronomy, Dr. Jason Lisle says:

"...the vastness and beauty of the universe declare God's glory. God could have chosen to create only the earth, sun and moon, and life would have been possible; but instead He chose to make a universe immense beyond imagination to give us just a small taste of His incredible magnificence." (emphasis mine)

What else is there to say on this, but:

"The heavens delcare the glory of God, and the sky above proclaims his handiwork."