The Universe In Perspective - Part 1, Our Solar System

It's all about perspective when trying to fathom the universe.  And one of the first questions that comes to mind is "Just how does our own corner of the cosmos here on Earth stack up against the rest of the universe?" To that end, I'm going to present a series of articles that, hopefully will help us get a grip on just how we measure up in the grand scheme of things.

So, on with Part 1: Our Solar System

Our Solar System is currently divided up into different classes of objects which include the Terrestrial Planets, the asteroids, the Gas Giants, Dwarf Planets, and TNO's (Trans-Neptunian Objects). Now, try not to be confused when I tell you that some of the Dwarf Planets are also TNO's, but not all of them - more about that shortly.

My job in this article is made a bit more difficult by the IAU (International Astronomical Union), which did that dastardly deed of demoting poor Pluto from full Planet status to Dwarf Planet. I say more difficult because where previously we had a nice, even, 9 (Hmmm,... that's odd) planets, now there are 8 Planets, a new Dwarf Planet that was once just an asteroid (Ceres), another Dwarf Planet that was once a Planet, and bunches of TNO's that most people have never even heard of before.

The picture on the bottom above is supposed to represent the Terrestrial Planets - planets that are rocky and mostly solid. But Pluto is listed there with no qualification. As far as we know, Pluto is indeed rocky and solid, but it would technically be a Dwarf planet. The picture on the top above shows Mercury, Venus, Earth, and Mars, left to right in order of their position/distance from the Sun.

The pictures above depict both the Terrestrial Planets and the Gas Giants. The picture on the bottom above shows all the planets with which most of us are familiar, along with Ceres (Dwarf Planet), and some TNO's that are also Dwarf Planets. But keep in mind that while Ceres is a Dwarf Planet, it is not a TNO. Confused yet? Well, go ahead, complain to the IAU and leave me the Heck alone!  :-) Especially because I'm not even going to TRY to explain this insanity in this article. Why? Because I just want to deal with size here. And we all know that it's really size that counts,... right? And not the angle of the planetary dangle!

And moving right along here, we now come to the REALLY big picture. No, not the actual size of the picture, you schmucks! I'm talking metaphorically here. The pics (yes, I know, but I'm gettin' tired of typing out the word picture all the way). Now, where was I? Oh, yes, the pics above should begin to give you a more impressive hint of perspective. You'll note that the Sun is waaaaaay bigger than anything else in our Solar System. The pic on the bottom above shows Jupiter, Saturn, Uranus, and Neptune from left to right spread across the disk of the Sun. Notice that the dark splotch approximately above Jupiter is a large but typical sunspot - even small sunspots are often larger than the entire Earth.

And, finally, for the sake of completeness and just plain for the Heck of it, the pic above is fairly self explanatory. Except maybe that just in case you don't recognize it, the Earth is hanging out at the bottom, only partially shown, just to give you something to compare all those other things/objects/TNOs/dwarf planets (and their moons) to. What? You've never heard of most of those Dwarf Planets and TNO's? Well, join the club - neither have a LOT of folks!! Must be some scientific conspiracy going on here,eh? Well, NO LONGER, cuz I've just exposed it now to the whole world,... or, um, at least to Gather!  :-)

Pretty Cool, eh?

Well, be sure to tune in for Part 2 - you think the Sun is big? Well, all I can tell ya is that you ain't seen nuthin yet!

© 2009 Gary D. Timothy

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Gather group:  Science In An Eclectic Universe

For more of my work: Eclectic's Universe blog Eclectic Universe website