SOLSYS.XLS - THE SCALE MODEL SOLAR SYSTEM SPREADSHEET
1998 - The Clark Foundation
The file SOLSYS.XLS is a spreadsheet that allows the user to calculate
the scale sizes, distances from the Sun, and velocities of the planets of
our Solar System.
This spreadsheet will work on both Macintosh and PC computers using
Microsoft Excel 4.0 or later.
** UNITS **
Because sizes and distances in the model can change dramatically
depending on how large or small a model Earth you use, sizes and
distances are calculated and displayed in a variety of units, both English
and metric. For example, if you make the scale model Earth very small,
it will be easier to understand distances in your model Solar System in
meters. If you make your model Earth large, then kilometers or miles are
more useful measurements of scale distances.
** THE REAL SOLAR SYSTEM **
Rows 6-16, columns A through I, display the true diameters of the Sun,
Moon, and Planets in kilometers (B6-B16), miles (C6-C16), and Earth
diameters (D6-D16).
Rows 7-16, columns E, F, and G, give the true average distances of the
planets from the Sun in millions of kilometers ("km^6", cells E7-E16),
millions of miles ("miles^6", cells F7-F16), and Astronomical Units
("A.U.", cells G7-G16). One A.U. is the average distance between Earth
and the Sun.
The periods of orbit (the time to complete one orbit) of the planets and
Earth's Moon (around Earth) is displayed in both years (cells H7-H16)
and days (cells I7-I16).
** CREATE A MODEL SOLAR SYSTEM **
To use the spreadsheet, enter the diameter of the scale model Earth you
want (in millimeters) into cell M1. The spreadsheet will then calculate
and display the following:
** SCALE **
The absolute scale of your new model Solar System is shown in cell M9.
For example, entering "50" in cell M1 (setting the size of your model
Earth to 50 millimeters -- about 2 inches) produces a scale of
1:255,120,000. This means that the sizes and distances in your model
Solar System are about two hundred fifty-five million times smaller than
reality.
Cell L10 displays the equivalents for converting 1 millimeter of scale
distance in your model into kilometers of actual distance. Cell L11
displays the corresponding conversion between scale model inches and
actual miles.
** SCALE DIAMETERS **
After the size of the scale model Earth has been entered in cell M1 the
spreadsheet calculates and displays the scale diameters of the Sun and
planets in millimeters (cells B21-B31), inches (cells C21-C31), and feet
(cells D21-D31).
** SCALE DISTANCES **
Scale distances between the Sun and each planet are displayed in
meters (cells E22-E31), kilometers (cells F22-F31), and miles (cells G22-
G31).
The average scale distance between the Moon and Earth is displayed in
cells L33-L36 in centimeters (cell L33), inches (cell L34), meters (cell
L35), and feet (cell L36).
** SCALE ORBITAL SPEEDS **
The scale speeds of the planets as they orbit the Sun are displayed in
centimeters per hour (cells L22-L31), and inches per hour (cells M22-
M31).
The average scale speed of the Moon as it orbits Earth is given in
millimeters per hour (cell L37), and inches per hour (cell L38).
** SCALE SPEED OF LIGHT **
The scale speed of light is displayed in kilometers per hour (cell L13),
miles per hour (cell L14), meters per second, (cell L15) and feet per
second (cell L16).
** SCALE DISTANCE TO ALPHA CENTAURI **
This spreadsheet helps the user understand that the planets of our Solar
System are tiny compared to the distances between them.
Understanding how large the distance is between our Sun and our
nearest neighboring star, Alpha Centauri, makes our Solar System seem
crowded by comparison. Scale distances between the Sun and Alpha
Centauri are displayed in kilometers (cell C34) and miles (cell C35).
** EXAMPLE MODEL **
Entering "2.55" as the scale size of Earth (cell M1) creates a scale of
approximately 1:5 billion (cell M9). The model Solar System is now one
five-billionth the size of the real Solar System. At this scale, one
millimeter in the model equals about 5,000 km (cell L10), and one inch
equals about 79,000 miles (cell L11).
At this scale the Sun’s diameter (cell B21) is about 280 mm (the size of a
basketball), and is not quite 30 meters (~100 feet) from a 2.55 millimeter
model Earth (cell B24) that is about the size of a small peppercorn.
The Moon is about the size of a poppy-seed (cell B25) and is 3 inches
(cell L34) from the peppercorn-sized Earth.
At a scale of 1:5 billion, the peppercorn-sized Earth still takes a year to
orbit the basketball-sized Sun at just over 2 centimeters per hour (cell
L24).
Jupiter is about the size of a cherry tomato (cells B27, C27, and D27)
and is about 155 meters (cell E27) from the Sun.
Shrinking the Solar System to a scale of 1:5 billion also creates a new
scale speed of light that is 5 billion times slower than the true speed of
light (about 300,000 km/sec.) It takes light from the Sun about 8.3
minutes to reach Earth. Reducing the speed of light to the scale
displayed in cell M9 creates a "scale speed of light" (cells L13-L16) that
is correct for the scale model Solar System.
Light from the scale model Sun still travels at a "scale" speed of 300,000
km per second, and will still arrive at the scale model of the Earth in a
little over 8 minutes. In this model Solar System, the Sun-Pluto distance
is reduced to just under 1,200 meters (cell E31), and the scale speed of
light is proportionately reduced to about six centimeters per second (cell
L15).
With the Solar System shrunk so small that the Sun is shrunk to the size
of a basketball, the distance to the Sun's closest neighboring star, Alpha
Centauri, is still greater than the distance between Salt Lake City and
London (cells C34 and C35).
Imagine a basketball-sized Sun 30 meters (100 feet) from a pepper-corn-
sized Earth. Tiny Pluto, a half-millimeter wide, lies nearly three-quarters
of a mile (1.2 km) away. Between this scale model Solar System and our
next closest star is an expanse of five thousand miles (8,100 km) of
emptiness. Similar distances separate the other 100 billion stars in our
galaxy.
Now you know why it’s called "space."