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We can use that mental image to imagine how much sunlight hits the planets. Looking from the position of the Sun, how much of the sky is blocked by planets? Scaled to a 2.2cm Earth-sized marble, the distance from the igloo-sized Sun to the marble-sized Earth would be more than a kilometer, not visible to the naked eye. Jupiter, a bit smaller than a volleyball, would also be "invisible" at 5.3 kilometer distance. To a first approximation, the solar system is empty.
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https://www.jpl.nasa.gov/edu/pdfs/scaless_reference.pdf Data from https://www.jpl.nasa.gov/edu/pdfs/scaless_reference.pdf and other sources

Scaling Earth to a Marble

One of my toys is a blue marble with green continents painted on it. It not perfectly round, but a few random measurements with a 10-micrometer-repeatable dial caliper average to 21.85 millimeters diameter. What if we scaled the solar system, planets and distances, so that the Earth was the size of that marble?

We can use that mental image to imagine how much sunlight hits the planets. Looking from the position of the Sun, how much of the sky is blocked by planets? Scaled to a 2.2cm Earth-sized marble, the distance from the igloo-sized Sun to the marble-sized Earth would be more than a kilometer, not visible to the naked eye. Jupiter, a bit smaller than a volleyball, would also be "invisible" at 5.3 kilometer distance. To a first approximation, the solar system is empty.

Here's a text snapshot of a crude spreadsheet that I created:

Earth-Marble Scaled Solar System

Marble Scaled

Radius

Distance

sun fraction

Diameter

Distance

km

km

AU

Scaled m

Scaled m

Sun

695700

2.386

0

Mercury

2440

5.790E+07

0.39

4.440E-10

10.7%

0.008

397

Venus

6052

1.062E+08

0.71

8.119E-10

19.5%

0.021

728

Earth

6371

1.496E+08

1.00

4.534E-10

10.9%

0.02185

1026

Mars

3386

2.279E+08

1.52

5.519E-11

1.3%

0.012

1563

Jupiter

69173

7.786E+08

5.20

1.973E-09

47.4%

0.237

5341

Saturn

57316

1.434E+09

9.58

3.997E-10

9.6%

0.197

9833

Uranus

25266

2.873E+09

19.20

1.934E-11

0.5%

0.087

19703

Neptune

24552

4.495E+09

30.05

7.458E-12

0.2%

0.084

30833

total

4.164E-09

100.0%

Data from https://www.jpl.nasa.gov/edu/pdfs/scaless_reference.pdf and other sources

EarthMarble (last edited 2022-12-08 09:46:58 by KeithLofstrom)