Monday, November 23, 2009

The Solar System to Scale

I think I've found what just might be the widest graphic on the Internet. It's the Solar System with the Sun and all the planets shown in a scale of 1 pixel = 1,000 km. It's not just the Sun and the planets out to Pluto (I think this was made before Pluto was demoted to dwarf planet status). It includes all the space between as well.

To get some idea of how big this is, I started on the left side and began scrolling by holding down the right arrow. At first it didn't look like anything was happening after the Sun scrolled off the left of the screen, but eventually a small image slid into view. It was Mercury and since it's to scale, there's not a whole lot of detail. I kept going and eventually Venus slid into view. More patience, then Earth and later Mars. After Mars I had to pause while I listened/watched with Klara McDonnell.

When I got back to the Solar System and resumed scrolling, I figured it had taken about 20 minues scrolling time just to get out to Jupiter. That's only about 1/7th of the way across, meaning it would have taken close to two and a half hours to get all the way over to Pluto. WikiAnswers says Pluto averages 328 light-minutes from the Sun, so that would mean the scrolling speed on my computer is about twice the speed of light. I guess that's pretty close since WikiAnswers says Jupiter averages 43.8 light-minutes from the Sun.

The Hitchhiker's Guide to the Galaxy has this to say about space:

"Space," it says, "is big. You just won't believe how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space."

When you spend 20 minutes scrolling at twice the speed of light to get from the Sun to Jupiter, you begin to get an idea how big the Solar System is, and that's far less than peanuts compared to the galaxy, which is immensely tiny compared to the universe.

It would take over two years of scrolling at the scale of the Solar System graphic to cover the distance to Alpha Centauri, by the way. I think my finger would get tired.


Laurel Kornfeld said...

Please do not blindly accept the controversial demotion of Pluto, which is still very much a matter of debate.Pluto is still a planet and should not be removed from this or any solar system model.

Only four percent of the IAU voted on the controversial demotion, and most are not planetary scientists. Their decision was immediately opposed in a formal petition by hundreds of professional astronomers led by Dr. Alan Stern, Principal Investigator of NASA’s New Horizons mission to Pluto. One reason the IAU definition makes no sense is it says dwarf planets are not planets at all! That is like saying a grizzly bear is not a bear, and it is inconsistent with the use of the term “dwarf” in astronomy, where dwarf stars are still stars, and dwarf galaxies are still galaxies. Also, the IAU definition classifies objects solely by where they are while ignoring what they are. If Earth were in Pluto’s orbit, according to the IAU definition, it would not be a planet either. A definition that takes the same object and makes it a planet in one location and not a planet in another is essentially useless. Pluto is a planet because it is spherical, meaning it is large enough to be pulled into a round shape by its own gravity--a state known as hydrostatic equilibrium and characteristic of planets, not of shapeless asteroids held together by chemical bonds. These reasons are why many astronomers, lay people, and educators are either ignoring the demotion entirely or working to get it overturned.

MobyD said...

I grew up thinking of Pluto as a planet, period. Like you, I don't think saying dwarf planets are not planets makes sense. So it follows that currently we have a total of 13 planets, with five considered dwarf plants: Ceres (in the asteroid belt), Pluto, Haumea, Makemake and Eris. I've always thought it was interesting that for a while Eris and its moon Dysnomia were unofficially known as Xena and Gabrielle.