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Jason_Roberts
2009-May-05, 06:53 PM
I have always found it very difficult to visualize and describe an accurate portrayal of distance and size regarding the bodies in our solar system. And I can never seem to relate to someone who doesn't understand astronomy very well, exactly how far apart some of these planets actually are especially in terms of orbit.

What's worse, is that the comparisons that I see on documentaries or in quick demonstrations on TV are almost never correct. Even on science shows!

The best ones I've come across are the soccer field, baseball park type analogies. The problem is, they either get the sizes wrong or are way, way too close together.

Does anyone have a good analogy that gets the idea across clearly and simply? The "if this baseball was the Earth and if this golf ball were Mars, they would be x amount of yards/miles apart" approach seems to work best for me, so far.

Does anyone know of a site or even a quick video clip that can illustrate these ideas in very easy-to-grasp, lay man terms? So far I've had no luck.

antoniseb
2009-May-05, 07:05 PM
How about: If the Sun were a dust speck five microns across in the goal of a soccer field, and the Earth orbited it with an orbit half a millimeter away from the speck, Alpha Centauri would be about as far away as the other goal.

Jason_Roberts
2009-May-05, 07:23 PM
How about: If the Sun were a dust speck five microns across in the goal of a soccer field, and the Earth orbited it with an orbit half a millimeter away from the speck, Alpha Centauri would be about as far away as the other goal.

I'm afraid they wouldn't know what a micron was.

(I am explaining the solar system to my niece. I probably should have mentioned that.)

But yeah, that's basically the idea.

...and the distance of the closest star has always kind of awed me, even on that scale.

Now if I could find a way just to narrow it down to every body in our solar system. I would have to wait before I could introduce something as big as interstellar space, though. I would keep it around the distance of Pluto or closer.

There's probably a bit of math I could do to make this easier on myself. Maybe scaling one AU down to an inch and half, or something along those lines.

Hm, but using AU isn't really helpful when the bodies are all in the same star system, I suppose.

kleindoofy
2009-May-05, 07:49 PM
There are a number of threads here on BAUT which describe scale models of our solar system. A search might help, or even better some BAUT member who can remember ...

Anyway, these models are on a correct scale and include driving for miles and miles along a road/highway to get to the next planet, which then turns out to be about the size of a baseball.

That should get your niece interested.

Hornblower
2009-May-05, 08:29 PM
If we use a baseball for the Earth, the Moon will be about 7 feet away, the Sun about 1/2 mile, and Pluto about 15 miles. That gives an idea of how tiny the planets are compared to the distances between them.

Jeff Root
2009-May-05, 08:39 PM
When I was in high school I drew a diagram of the Solar System on my
bedroom wall at the scale of 1:1 trillion. The Sun was a circle 1.4 mm in
diameter. (Carefully-pointed 3H lead in an engineer's mechanical pencil.)
Mercury was the smallest point I could make (supposed to be less than
0.005 mm diameter), 5.8 cm away. Earth was a dot not much larger than
Mercury (supposed to be a little over 0.01 mm diameter), 15 cm away.
Jupiter was a dot 0.14 mm in diameter (1/10th the diameter of the Sun),
78 cm away. Saturn was a smaller dot, 1.4 meters from the Sun. Uranus
was an even smaller dot, 2.8 meters from the Sun. And Neptune was
about a meter beyond the length of my bedroom wall. The nearest star,
Proxima Centauri, was about 40 km away.

Here is my web page with a diagram of the Solar System at a scale of
1 pixel = 1 million kilometers: Planet distances (http://www.freemars.org/jeff/planets/solsys.htm)

-- Jeff, in Minneapolis

Jason_Roberts
2009-May-05, 08:49 PM
If we use a baseball for the Earth, the Moon will be about 7 feet away, the Sun about 1/2 mile, and Pluto about 15 miles. That gives an idea of how tiny the planets are compared to the distances between them.

Thanks.

When I was in high school I drew a diagram of the Solar System on my
bedroom wall at the scale of 1:1 trillion. The Sun was a circle 1.4 mm in
diameter. (Carefully-pointed 3H lead in an engineer's mechanical pencil.)
Mercury was the smallest point I could make (supposed to be less than
0.005 mm diameter), 5.8 cm away. Earth was a dot not much larger than
Mercury (supposed to be a little over 0.01 mm diameter), 15 cm away.
Jupiter was a dot 0.14 mm in diameter (1/10th the diameter of the Sun),
78 cm away. Saturn was a smaller dot, 1.4 meters from the Sun. Uranus
was an even smaller dot, 2.8 meters from the Sun. And Neptune was
about a meter beyond the length of my bedroom wall. The nearest star,
Proxima Centauri, was about 40 km away.

Here is my web page with a diagram of the Solar System at a scale of
1 pixel = 1 million kilometers: Planet distances (http://www.freemars.org/jeff/planets/solsys.htm)

-- Jeff, in Minneapolis

Thanks.

robross
2009-May-05, 08:56 PM
I have always found it very difficult to visualize and describe an accurate portrayal of distance and size regarding the bodies in our solar system. And I can never seem to relate to someone who doesn't understand astronomy very well, exactly how far apart some of these planets actually are especially in terms of orbit.

What's worse, is that the comparisons that I see on documentaries or in quick demonstrations on TV are almost never correct. Even on science shows!

The best ones I've come across are the soccer field, baseball park type analogies. The problem is, they either get the sizes wrong or are way, way too close together.

Does anyone have a good analogy that gets the idea across clearly and simply? The "if this baseball was the Earth and if this golf ball were Mars, they would be x amount of yards/miles apart" approach seems to work best for me, so far.

Does anyone know of a site or even a quick video clip that can illustrate these ideas in very easy-to-grasp, lay man terms? So far I've had no luck.

There's a youtube video that should get you exactly what you are looking for. I'd paste the direct url but since I'm a newbie my post would have to wait to be moderated.

But if you go to the universe today web site, and on the right hand side, under "Most Popular Articles", click on the "What is the Biggest Star in the Universe" link. Then scroll to the end of the article, and watch the youtube video there.

Rob

PraedSt
2009-May-05, 08:59 PM
Yes, but some of us need Metric! :)

redshifter
2009-May-05, 09:00 PM
Here's an interesting video of the scale of planets in our solar system as well as some other stars: http://www.youtube.com/watch?v=x1w8hKTJ2Co

raptorthang
2009-May-05, 09:15 PM
Scale models are useful. However, when used to explain the really big and the really small we sometimes confuse understanding 'the model' with the reality that the model is trying to interpret.

'The sun is a basketball and the earth is a marble 'x' number of feet away and Mars is .....' the issue is that we don't have a perceptual means to understand the first variable so that twice the distance of the Earth or a hundred times that first variable mean what? We say to someone something like '1 foot is equal to 90 million miles' and the answer will be 'ok'. Actually it's not 'ok' because we have the means to visualize a foot but not to visualize 90 million miles. 90 million miles is a number and twice that is a number and so on. 90 million miles isn't something we can relate to with our physical senses. So the Earth is a long way from the Sun and Mars is even further and Jupiter way further still.

This doesn't diminish the value of scale models because there is nothing else we can relate to that is more useful. We have this same issue in my field, geology. We start to visualize charts with time relationships that are just that...charts. One can't get ones head around 'a million' years... so 325 times that back to the Carboniferous is just a number and not an 'understanding' regardless of what scale it is put on.

Tog
2009-May-05, 10:19 PM
State Street in Salt Lake City runs straight for about 12 miles and ends at the state capitol building.

We took a scale of 1 mile per AU and drew it over a map of the city. Earth at this scale was about 5.3 inches across, so about the diameter of a CD. The speed of light to this scale was about 8 miles per hour. A cool side effect was the scale position of Proxima Centauri was pretty close to the real position of the moon.

You might be able to get or make a scale overlay for Google Earth that will plot the solar system over the top of your home town in a similar way. Then take a trip down the street with few paper cutouts. Odds are really good, she won't want to go all the way to Mars. I doubt I would.:)

Jason_Roberts
2009-May-05, 10:41 PM
Here's an interesting video of the scale of planets in our solar system as well as some other stars: http://www.youtube.com/watch?v=x1w8hKTJ2Co

Ah, I actually have that one bookmarked as well as some of its variants.

Where it shows scale very well, it wasn't really able to help me with the distance aspect of things.

Notoriously cool video though.

Jason_Roberts
2009-May-05, 10:46 PM
State Street in Salt Lake City runs straight for about 12 miles and ends at the state capitol building.

We took a scale of 1 mile per AU and drew it over a map of the city. Earth at this scale was about 5.3 inches across, so about the diameter of a CD. The speed of light to this scale was about 8 miles per hour. A cool side effect was the scale position of Proxima Centauri was pretty close to the real position of the moon.

You might be able to get or make a scale overlay for Google Earth that will plot the solar system over the top of your home town in a similar way. Then take a trip down the street with few paper cutouts. Odds are really good, she won't want to go all the way to Mars. I doubt I would.:)

This sounds like something fun.

I have a feeling that, by the end of this, I will be compelled to create my own video of sizes and distances in our solar system.

robross
2009-May-05, 11:20 PM
This sounds like something fun.

I have a feeling that, by the end of this, I will be compelled to create my own video of sizes and distances in our solar system.

You could create a similar animation using points/spheres as relative distances between known objects - Sun to Mercury, Sun to Earth, Sun to Pluto, etc, . But I imagine there's quite a jump from Sun to Heliopause and Sun to Alpha Centauri.

JustAFriend
2009-May-05, 11:59 PM
There are a number of scale model solar systems at various museums where you can walk from one planet to another... here is a page that links to some and also has several models, including those based on classroom globes and sports fields:

http://en.wikipedia.org/wiki/Solar_system_model

Jason_Roberts
2009-May-06, 12:24 AM
There are a number of scale model solar systems at various museums where you can walk from one planet to another... here is a page that links to some and also has several models, including those based on classroom globes and sports fields:

http://en.wikipedia.org/wiki/Solar_system_model

Neat!

This is by far one of the coolest displays I've ever seen: The Sweden Solar System (http://en.wikipedia.org/wiki/Sweden_Solar_System)

It represents the Sun at a whopping 110m (360 feet) in diameter with the other bodies, spread northward throughout other cities along the Baltic coastline. The Earth is 4.7 miles from this location, and is 2.1 feet in diameter.

Once Mars comes into things the distances start to become pretty intimidating.

Delvo
2009-May-06, 01:07 AM
State Street in Salt Lake City runs straight for about 12 miles and ends at the state capitol building...To show the planets in a realistic distribution instead of a straight line as they often end up in models, you could use a city with a concentric ring layout, if the person you're talking to is familiar with one. Unfortunately, there aren't many such cities; the only one I know of is Washington.

Maybe irrigation circles would work better in rural areas.

When my sister asked me what exactly a light year was, I worked out an analogy at one thousand miles, which happens to be roughly the distance between our homes. On that scale, the sun ended up between 8 and 9 inches wide (nifty sports ball analogy perhaps), and the Earth ended up a twelfth of an inch wide