Sun 1391900 27.4 696 Calculate Clear

Mercury 4866 0.0957 2.4 57950000 95 ft 0.82 in 28.977 m

Venus 12106 0.2383 6 108110000 177 ft 4.3 in 54.058 m

Earth 12742 0.2508 6.3 149570000 245 ft 4.5 in 74.79 m

Mars 6760 0.133 3.3 227840000 373 ft 9.36 in 113.928 m

Jupiter 142984 2.8148 71.4 778140000 1276 ft 6.81 in 389.097 m

Saturn 116438 2.2922 58.2 1427000000 2341 ft 0.56 in 713.551 m

Uranus 46940 0.924 23.4 2870300000 4708 ft 10.02 in 1435.253 m

Neptune 45432 0.8943 22.7 4499900000 7382 ft 3.07 in 2250.111 m

Pluto 2274 0.044 1.1 5913000000 9700 ft 6 in 2956.712 m

Other interesting distances and speeds

QuantityReal

Quantity

ScaledQuantity(English)

ScaledQuantity(Metric)

Speed oflight

299792 km/sec 5.901 in/sec 149.9 mm/sec

Lightyear

9.46051E+12 km 2939.4 mi 4730.5 km

Distances to Stars and GalaxiesTo Alpha Centauri 4.03964E+13 km 12551.4 mi 20199.6 km

To Sirius 8.17388E+13 km 25396.8 mi 40872.3 km

To Deneb 1.32636E+16 km 4121105.5 mi 6632276.4 km

To Galacticcenter

2.62151E+17 km 81452391.1 mi 131084917 km

Sizes of StarsHottest star(Type 05)

12527100 km 20.55ft 6.26 m

Coolest star(Type M5)

222704 km 4.38 in 11.13 cm

Red giant 521962500 km 856.2 ft 261 m

(Betelgeuse)White dwarf(Sirius B)

13919 km 0.274 in 6.96 mm

Neutron star 20 km 0.000393 in 0.01 mm

I've only given you the sizes and distances to the planets. If you'd like tosee the satellites of the planets as well, click here for a much moreextensive page (and a longer download time too!)

One of the most exciting excercises I ever did as a kid was to make a scale model ofthe Solar System. Most of the pictures in my books made the distance betweenplanets seem small and easy to travel. Museums were no help either. The modelsthey displayed usually had the sizes of the planets to scale, but the distancesbetween them were a completly different scale, giving the impression of a ratherclose-knit family.

I made my first scale model on a roll of teletype paper tape (anyone remember thatstuff?) On this 1-inch tape, my Sun was the size of the tape - 1 inch in diameter. Itall started out well. Mercury was only about 3-1/2 feet from the sun and Earth wasalmost 9 feet from the Sun. What I didn't bargain for was that Pluto was 354 feetdown the tape! I used up almost the entire roll.

I also calculated the sizes that I should make the dots that represented the planets. Ifound that even the largest planet, Jupiter, should have a spot size smaller than 1/8inch. The other planets, especially the small rocky inner planets, would be virtuallyinvisible dust spots.

Needless to say, this was an eye-opening experience. This one excercise taught methe real meaning of the word "space." It sure made me feel insignificant looking atthe scale of the Solar System - never mind the rest of the universe!

Now we have great tools like spreadsheets to do the numerical computations for us.Below you can download OpenOffice or Excel format files. In this spreadsheet, youset the scale of the model by entering a radius for the Sun. The sheet should thencalculate everything else based on this number.

Download OpenOffice-format spreadsheet (25 kbytes)

Download Excel-format spreadsheet (45 kbytes)

Links to other Solar System resources

Your Age On Other Worlds

7/24/15, 2:36 PMBuild a Solar System

Page 1 of 4http://www.exploratorium.edu/ronh/solar_system/all_bodies.html

Make a scale model of the Solar System and learn the REAL definitionof "space."

You must have JavaScript turned on in your browser!

Fill in the diameter of the Sun you want your model to be scaled by. You can fill ineither the red bordered inches box or the green bordered millimeters box. Important:Only fill in one box. If both are filled in you will get a dialog box asking you to clearone of the boxes. Use the Clear button to clear the entire form.

Click on the "Calculate" button.

Notice that the distances and sizes of the planets will automatically fill in. I've alsoprovided some other interesting scale comparisons at the bottom of the chart.

You can now build your scale model. You can do this with a long tape measure, or youcan measure the size of your pace and walk it off counting the number of steps youtake. To mark a planet's place you can use a piece of paper on a post that you stickinto the ground, or you can use a flag, or even a person. Be prepared for a long walk!

If you build your solar system on a roll of toilet paper, you can make the Sun about .4inches (10 mm) across and still fit the entire solar system on the roll. A standard rollof toilet paper has about 450 sheets that are about 4.375 inches long, hence the roll isabout 164 feet long. You should check your toilet paper for length. Some are longer.

You can click on the names of the planets and satellites to go the the Nine Planets website page about them. LOTS of info there!

Body

BodyDiam(km)

BodyDiam(in)

BodyDiam(mm)

Orbitradius(km)

Scaled orbitradius

(ft & in)

Scaledorbit

radius(meters)

Sun 1391900 27.4 696 Calculate Clear

Mercury 4866 0.0957 2.4 57950000 95 ft 0.82 in 28.977 m

Venus 12106 0.2383 6 108110000 177 ft 4.3 in 54.058 m

7/24/15, 2:36 PMBuild a Solar System

Page 2 of 4http://www.exploratorium.edu/ronh/solar_system/all_bodies.html

Earth 12742 0.2508 6.3 149570000 245 ft 4.5 in 74.79 m

Moon 3476 0.0684 1.7 384403 0 ft 7.56 in 0.192 m

Mars 6760 0.133 3.3 227840000 373 ft 9.36 in 113.928 m

Phobos 22 0.0004 0 9408 0 ft 0.18 in 0.004 m

Deimos 12 0.0002 0 23457 0 ft 0.46 in 0.011 m

Jupiter 142984 2.8148 71.4 778140000 1276 ft 6.81 in 389.097 m

Metis (XVI) 40 0.0007 0 128000 0 ft 2.51 in 0.064 m

Adrastea (XIV) 20 0.0003 0 129000 0 ft 2.53 in 0.064 m

Amalthea (V) 188 0.0037 0 181400 0 ft 3.57 in 0.09 m

Thebe (XV) 100 0.0019 0 222000 0 ft 4.37 in 0.111 m

Io (I) 3642 0.0716 1.8 421900 0 ft 8.3 in 0.21 m

Europa (II) 3130 0.0616 1.5 671200 1 ft 1.21 in 0.335 m

Ganymede (III) 5268 0.1037 2.6 1071000 1 ft 9.08 in 0.535 m

Callisto (IV) 4806 0.0946 2.4 1880000 3 ft 1.01 in 0.94 m

Leda (XIII) 16 0.0003 0 11110000 18 ft 2.71 in 5.555 m

Himalia (VI) 186 0.0036 0 11470000 18 ft 9.8 in 5.735 m

Lysithea (X) 36 0.0007 0 11710000 19 ft 2.52 in 5.855 m

Elara (VII) 76 0.0014 0 11740000 19 ft 3.11 in 5.87 m

Ananke (XII) 30 0.0005 0 20700000 33 ft 11.5 in 10.35 m

Carme (XI) 40 0.0007 0 22350000 36 ft 7.99 in 11.175 m

Pasiphae (VIII) 50 0.0009 0 23500000 38 ft 6.63 in 11.75 m

Sinope (IX) 36 0.0007 0 23700000 38 ft 10.56 in 11.85 m

Saturn 116438 2.2922 58.2 1427000000 2341 ft 0.56 in 713.551 m

Pan (XVIII) 20 0.0003 0 133583 0 ft 2.62 in 0.066 m

Atlas (XV) 30 0.0005 0 137670 0 ft 2.71 in 0.068 m

Prometheus (XVI) 92 0.0018 0 139350 0 ft 2.74 in 0.069 m

Pandora (XVII) 84 0.0016 0 141700 0 ft 2.78 in 0.07 m

Epimetheus (XI) 114 0.0022 0 151420 0 ft 2.98 in 0.075 m

Janus (X) 178 0.0035 0 151470 0 ft 2.98 in 0.075 m

Mimas (I) 398 0.0078 0.1 185540 0 ft 3.65 in 0.092 m

Enceladus (II) 498 0.0098 0.2 239040 0 ft 4.7 in 0.119 m

Tethys (III) 1060 0.0208 0.5 294670 0 ft 5.8 in 0.147 m

7/24/15, 2:36 PMBuild a Solar System

Page 3 of 4http://www.exploratorium.edu/ronh/solar_system/all_bodies.html

Telesto (XIII) 30 0.0005 0 294870 0 ft 5.8 in 0.147 m

Calypso (XIV) 26 0.0005 0 294870 0 ft 5.8 in 0.147 m

Helene (XII) 33 0.0006 0 377400 0 ft 7.42 in 0.188 m

Dione (IV) 1120 0.022 0.5 377420 0 ft 7.43 in 0.188 m

Rhea (V) 1528 0.03 0.7 527070 0 ft 10.37 in 0.263 m

Titan (VI) 5150 0.1013 2.5 1221860 2 ft 0.05 in 0.61 m

Hyperion (VII) 286 0.0056 0.1 1481000 2 ft 5.15 in 0.74 m

Iapetus (VIII) 1436 0.0282 0.7 3560800 5 ft 10.09 in 1.78 m

Phoebe (IX) 220 0.0043 0.1 12954000 21 ft 3.01 in 6.477 m

Uranus 46940 0.924 23.4 2870300000 4708 ft 10.02 in 1435.253 m

Cordelia (VI) 26 0.0005 0 49752 0 ft 0.97 in 0.024 m

Ophelia (VII) 32 0.0006 0 53764 0 ft 1.05 in 0.026 m

Bianca (VIII) 44 0.0008 0 59165 0 ft 1.21 in 0.03 m

Cressida (IX) 66 0.0012 0 61767 0 ft 1.21 in 0.03 m

Desdemona (X) 58 0.0011 0 62659 0 ft 1.23 in 0.031 m

Juliet (XI) 84 0.0016 0 64358 0 ft 1.26 in 0.032 m

Portia (XII) 110 0.0021 0 66097 0 ft 1.3 in 0.033 m

Rosalind (XIII) 54 0.001 0 69927 0 ft 1.48 in 0.037 m

Belinda (XIV) 68 0.0013 0 75255 0 ft 1.48 in 0.037 m

Puck (XV) 154 0.003 0 86006 0 ft 1.69 in 0.043 m

Miranda (V) 472 0.0092 0.2 129400 0 ft 2.54 in 0.064 m

Ariel (I) 1162 0.0228 0.5 191800 0 ft 3.77 in 0.095 m

Umbriel (II) 1170 0.023 0.5 267200 0 ft 5.26 in 0.133 m

Titania (III) 1578 0.031 0.7 438600 0 ft 8.63 in 0.219 m

Oberon (IV) 1522 0.0299 0.7 586100 0 ft 11.53 in 0.293 m

Neptune 45432 0.8943 22.7 4499900000 7382 ft 3.07 in 2250.111 m

Naiad (III) 58 0.0011 0 48200 0 ft 0.94 in 0.024 m

Thalassa (IV) 80 0.0015 0 50000 0 ft 0.98 in 0.025 m

Despina (V) 148 0.0029 0 52600 0 ft 1.03 in 0.026 m

Galatea (VI) 158 0.0031 0 62000 0 ft 1.22 in 0.031 m

Larissa (VII) 193 0.0037 0 73600 0 ft 1.44 in 0.036 m

Proteus (VIII) 418 0.0082 0.2 117600 0 ft 2.31 in 0.058 m

Triton (I) 2706 0.0532 1.3 353100 0 ft 6.95 in 0.176 m

7/24/15, 2:36 PMBuild a Solar System

Page 4 of 4http://www.exploratorium.edu/ronh/solar_system/all_bodies.html

Nereid (II) 340 0.0066 0.1 5900000 9 ft 8.15 in 2.95 m

Pluto 2274 0.044 1.1 5913000000 9700 ft 6 in 2956.712 m

Charon 1172 0.023 0.5 17500 0 ft 0.34 in 0.008 m

Other interesting distances and speeds

QuantityReal

Quantity

ScaledQuantity(English)

ScaledQuantity(Metric)

Speed oflight

299792 km/sec 5.901 in/sec 149.9 mm/sec

Lightyear

9.46051E+12 km 2939.4 mi 4730.5 km

Distances to Stars and GalaxiesTo Alpha Centauri 4.03964E+13 km 12551.4 mi 20199.6 km

To Sirius 8.17388E+13 km 25396.8 mi 40872.3 km

To Deneb 1.32636E+16 km 4121105.5 mi 6632276.4 km

To Galacticcenter

2.62151E+17 km 81452391.1 mi 131084917 km

Sizes of StarsHottest star(Type 05)

12527100 km 20.55 ft 6.26 m

Coolest star(Type M5)

222704 km 4.38 in 11.13 cm

Red giant(Betelgeuse)

521962500 km 856.2 ft 261 m

White dwarf(Sirius B)

13919 km 0.274 in 6.96 mm

Neutron star 20 km 0.000393 in 0.01 mm

Return to top page

© 1997; Ron Hipschman , Exploratorium

Want to melt those years away? Travel to an outer planet!

This Page requires a JavaScript capable browser.

Fill in your birthdate below in the space indicated. (Note you must enter the yearas a 4-digit number!)Click on the "Calculate" button.Notice that your age on other worlds will automatically fill in. Notice thatYour age is different on the different worlds. Notice that your age in "days"varies wildly.Notice when your next birthday on each world will be. The date given is an"earth date".You can click on the images of the planets to get more information about themfrom Bill Arnett's incredible Nine Planets web site.

MM DD YYYY01 01 2002 Calculate

MERCURY

Your age is

83.6 Mercurian days 55.7 Mercurian years

Next Birthday Sun, Jun 28, 2015

VENUS

Your age is

20.1 Venusian days 21.8 Venusian years

Next Birthday Wed, Jul 15, 2015

EARTH

Your age is

4900.1 Earth days 13.4 Earth years

Next Birthday Fri, Jan 1, 2016

MARS JUPITER SATURN

Your age is4757.4 Martian days 7.1 Martian years

Next Birthday Tues, Jan 17, 2017

Your age is11951.7 Jovian days 1.13 Jovian years

Next Birthday Mon, Sep 22, 2025

Your age is10889.3 Saturnian days 0.45 Saturnian years

Next Birthday Tues, Jun 17, 2031

URANUS

Your age is6805.8 Uranian days 0.15 Uranian years

Next Birthday Sat, Jan 5, 2086

NEPTUNE

Your age is7313.7 Neptunian days 0.08 Neptunian years

Next Birthday Sat, Oct 18, 2166

PLUTO

Your age is766.8 Plutonian days 0.053 Plutonian years

Next Birthday Fri, Aug 9, 2250

The Days (And Years) Of Our Lives

Looking at the numbers above, you'll immediately notice thatyou are different ages on the different planets. This brings upthe question of how we define the time intervals we measure.What is a day? What is a year?

The earth is in motion. Actually, several different motions all atonce. There are two that specifically interest us. First, the earthrotates on its axis, like a spinning top. Second, the earthrevolves around the sun, like a tetherball at the end of a stringgoing around the center pole.

The top-like rotation of the earth on its axis is how wedefine the day. The time it takes the earth to rotate fromnoon until the next noon we define as one day. Wefurther divide this period of time into 24 hours, each of

which is divided into 60 minutes, each of which is broken into 60seconds. There are no rules that govern the rotation rates of theplanets, it all depends on how much "spin" was in the originalmaterial that went into forming each one. Giant Jupiter has lotsof spin, turning once on its axis every 10 hours, while Venustakes 243 days to spin once.

The revolution of the earth around the sun is how we define theyear. A year is the time it takes the earth to make one revolution- a little over 365 days.

We all learn in grade school that the planets move at differingrates around the sun. While earth takes 365 days to make onecircuit, the closest planet, Mercury, takes only 88 days. Poor,ponderous, and distant Pluto takes a whopping 248 years for onerevolution. Below is a table with the rotation rates and revolutionrates of all the planets.

Planet Rotation Period Revolution Period

Mercury 58.6 days 87.97 days

Venus 243 days 224.7 days

Earth 0.99 days 365.26 days

Mars 1.03 days 1.88 years

Jupiter 0.41 days 11.86 years

Saturn 0.45 days 29.46 years

Uranus 0.72 days 84.01 years

Neptune 0.67 days 164.79 years

Pluto 6.39 days 248.59 years

Why the huge differences in periods? We need to go back to thetime of Galileo, except that we're not going to look at his work,but rather at the work of one of his contemporaries, JohannesKepler (1571-1630).

Ever wonder what you might weigh on Mars or The Moon? Here's yourchance to find out.

This Page requires a JavaScript capable browser.

Fill in your weight below in the space indicated. You can enter your weight in anyunit you wish.Click on the "Calculate" button.Notice that the weights on other worlds will automatically fill in. Notice that yourweight is different on the different worlds.You can click on the images of the planets to get more information about them fromBill Arnett's incredible Nine Planets web site.

100 Calculate

The PlanetsMERCURY

Your weight is37.8

VENUS

Your weight is90.7

THE MOON

Your weight is16.6

MARS

Your weight is37.7

JUPITER

Your weight is236.4

SATURN

Your weight is106.4

URANUS

Your weight is88.9

NEPTUNE

Your weight is112.5

PLUTO

Your weight is6.7

The Moons of JupiterIO

Your weight is18.35

EUROPA

Your weight is13.35

GANYMEDE

Your weight is14.48

CALLISTO

Your weight is12.64

A Few Different Types of Stars(better land at night to avoid burning your feet!)

THE SUN

Your weight is2707.2

A WHITE DWARF

Your weight is130000000

A NEUTRON STAR

Your weight is14000000000000

Mass and Weight

Before we get into the subject of gravity and how it acts, it's important tounderstand the difference between weight and mass.

SetUp Markers -

REMEMBER - PUT PLANETS ON & OFF STAKES EVERY CLASS!

1) Sol = 1st (N) Speed Bump by TurnPike

2) Mercury = Big Stone McM Sign

3) Venus = (S) End 1st (W) String of Cars

4) Earth = 2nd (S) Speed Bump

5) Mars = 1/2 way btw. 2 (S) McM Stop Signs

6) Asteroids mn. = (N) end CES P-Patch

7) Jupiter = (N) side bench btw. McM-VHS

8) Saturn = 3 Trees (S) of Sr. Rock

(district end ~ 850 m)