# Thread: "Looking Up" and "Looking Down"

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## "Looking Up" and "Looking Down"

Hi there! I'm new and I have two questions if anyone would care to help.

Question 1: From the perspective of the Sun, are all the planets at the same elevation? By that I mean if all the orbits were synchronized, would they all be in a straight line or would some planets be "higher" or "lower" than others?

Question 2: Again from the perspective of the Sun, we always talk about going further "out" with probes and such, but what about going "up" or "down" on the z-axis? Is there anything to explore in that vein?

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Yes, Some planets are higher or lower than others. Some pronouncably so.
From the perspective of Earth looking upward we see them on the Plane of the Ecliptic.

Going outward is 3 - dimensional. Which direction you go depends on where you are trying to go.

Didn't you see Star Trek two? It's how Kirk caught Kahn by surprise. <chuckle>

Bear in mind that going outward isn't as simple as pointing a rocket ship at your destination.
For example:
Its very difficult to launch something into the Sun! Sounds crazy right?
Probes launched toward the inner planets were actually launched toward Jupiter first- then made the journey to Venus etc.

3. Bob B just posted a good illustration of Mars and Earth over here for another discussion.

4. Originally Posted by Neverfly
Yes, Some planets are higher or lower than others. Some pronouncably so.
I think I'd say it different. They vary, but it's not so pronouncably so. It's slight.

The JPL Small-Body Database orbit diagram is a handy interactive way to look at the system from all angles, if your computer does Java. I linked to a diagram of Halley's Comet, because I knew it offered a little 3D action.

See that the planets stay pretty much in a plane, save now-nonplanet Pluto. Measurably the planets are not in a perfect plane, but it's not very noticeable on the large scale.

Click on the thumbnail to enlarge, to see one view.
orbitdiagram.gif

Pluto, Halley's and other small bodies are more likely to be found somewhat above or below the plane.

Traveling in or out from the sun is mostly done in the plane. That's where most stuff to look at is, and it's cheaper in energy cost to just add on to the motion the Earth naturally gives to a spacecraft, than to try to go above or below the plane.

I'm sure a small number of missions have moved out of the plane some. Can't think of their names or descriptions. Someone will probably provide them.

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V'ger did

I say that as a joke but I'm also actually serious.
I think...

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Originally Posted by Bitter End
Hi there! I'm new and I have two questions if anyone would care to help.

Question 1: From the perspective of the Sun, are all the planets at the same elevation? By that I mean if all the orbits were synchronized, would they all be in a straight line or would some planets be "higher" or "lower" than others?
Other than Pluto, which is inclined by about 17 degrees, the other planets are in-line within a few degrees.

A good site to bone up on planets is The (Nine)8 Planets

Originally Posted by Bitter End
Question 2: Again from the perspective of the Sun, we always talk about going further "out" with probes and such, but what about going "up" or "down" on the z-axis? Is there anything to explore in that vein?
The probes we've sent are primarily designed to explore the planets, Kuiper Belt and other interesting things within our solar system. Most interesting things in our SS are in the same plane.

The one thing that is not, is the Oort cloud - where comets live. It is spherical, which means it's just as easy to explore it in the plane of the SS as out.

However, Neverfly is correct; Voyager 1 and 2, having explored the inner SS are both on paths out of the plane of our SS, one in each direction.

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Not to contest with the bigger brains here..

But Bitterend, can you specify what you mean by "same elevation"?

The consense is that on the large scale - yes
But on the small initimate scale- not quite.

Just to ensure you have the answer that you are looking for

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I have definitely received the answer I was looking for. Thanks all!!

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I'm going to try to use it to alleviate some of my own ignorance.

As stated above the planets mostly seem to be on a plane.
Yet the often taught concept is a "gravity well" using the example of a heavy ball on a spread sheet with a lighter ball rolling in toward it.

Now I realize that this is probably similar to how an atom is taught looking like a ball with a ball orbiting it...

But can a gravity well be defined as conical extending above and below a planet?
Because if Lightweight contender Mars is at the same elevation as Sumo wrestlin Jupiter...

10. Originally Posted by Neverfly
But can a gravity well be defined as conical extending above and below a planet?
A gravity well can be defined as a conical extending in any 3D direction because it is only a 2D visualization effect.

The 2D plane expressed (the sheet in the ball/sheet example) is the plane that contains the elliptical path of influence*.

*That sounds more technical than how I'm visualizing it. I hope I'm expressing it correctly.

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Maybe it's like a tessaract. My problem is that Im trying to visualize it in my head and my brain rebels.

12. Originally Posted by Neverfly
Maybe it's like a tessaract.
Bingo... The visualization is one dimension removed from the actual effect.

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Since I was a kid, this is one thing that has always eluded my higher consciousness.

Doing away with the visualization causes me to think that the plane of the ecliptic doesn't make sense. Because then it wouldnt NEED to be on a plane. Yet it is.

14. Here. A picture such as this one, found on this site helps me extend the rubber sheet with gridlines into a more correct the 3d effect.

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On the visual level, (ugh!) i can "see" how a plane might occur with vastly different masses going by that fist links Interpretation...

Hey thanks neowatcher for the tutoring.

I think Im going to do some reading and try to persuade my mind to stop trying to visualize tessaracts.

16. The one probe I can think of that deliberately went out of the normal plane is Ulysses, which went around the sun in the "wrong" plane, in order to investigate the north and south poles of the sun. But obviously not very far above the plane, because it was only going around the sun.

17. Originally Posted by Neverfly
Doing away with the visualization causes me to think that the plane of the ecliptic doesn't make sense. Because then it wouldnt NEED to be on a plane. Yet it is.
The "canvas" analogy for gravity uses two dimensions as an analogy for three; gravity works equaly in all three dimensions.

The plane of the solar system isn't because of gravity having that shape. It has nothing to do with gravity. It's just because all of the planets and the sun formed from the same original cloud of loose stuff, which was rotating, so they all inherited the rotation of the original cloud.

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Originally Posted by Delvo
The "canvas" analogy for gravity uses two dimensions as an analogy for three; gravity works equaly in all three dimensions.

The plane of the solar system isn't because of gravity having that shape. It has nothing to do with gravity. It's just because all of the planets and the sun formed from the same original cloud of loose stuff, which was rotating, so they all inherited the rotation of the original cloud.
This is a common theme in the solar system and in galaxies. Flat like a pizza. It is not, however, set in stone. Elliptical galaxies that look like ball.

Im thinking now of pizza dough. The chef tosses it up, spinning.

19. There are also irregular galaxies that have no real shape at all.

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Originally Posted by davidlpf
There are also irregular galaxies that have no real shape at all.
Ok now Im thinking of the pizza chef blasting a horrifying sneeze...

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You know, it just occurred to me reading this thread that there's no reason why gravity well diagrams have to be limited to a 2D grid.

Sure it's the best way to explain the phenom simply, but A 3D grid can be built as well.

The warp though, rather than going "down" in the centre of a well, would simply go "inward" from all directions.

Perhaps someday I'll make a demo of that, just to show it can be done.

22. Instead of a grid, you could also use color shading or even a dot field, where the color gets more intense or the dots' arrangement gets denser as you get closer to the center. For that matter, if you can use a 3D grid where the lines are bent, you can also use a 2D grid where the lines are bent.

All of these have the advantage of only needing to represent 2 dimensions, a cross-section through the middle of a 3D region, with the 2 dimensions of the image, instead of trying to put more dimensions of information in the image than it can actually hold. The third dimension is pretty easily implicit from this 2D cross-section, since people are used to seeing cross-sections and knowing that there's a third dimension that isn't shown.

The 2D grid with the vertical distortions always seemed funny to me: if you're viewing it on a TV/computer screen or printed on paper, then the dimension count gets wacky even before you consider the gravitational concept it's supposed to represent or how its dimensions relate to the real ones: just the picture itself is already a 2D illustration of a 3D model of a 2D plane distorted into 3D space.

23. Originally Posted by DaveC426913
You know, it just occurred to me reading this thread that there's no reason why gravity well diagrams have to be limited to a 2D grid.
Maybe post 14 helped occur it for you.

24. ## Re: "Looking Up" and "Looking Down"

Originally Posted by Jens
The one probe I can think of that deliberately went out of the normal plane is Ulysses, which went around the sun in the "wrong" plane, in order to investigate the north and south poles of the sun. But obviously not very far above the plane, because it was only going around the sun.
Don't forget Voyager 1.

25. Originally Posted by Maksutov
And 2 (oh, and Pioneer 10&11 to a minor extent even though they went silent)
http://www.heavens-above.com/solar-escape.asp

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27. Originally Posted by Neverfly
There's no evidence it was outside the plane.

Like all inbound objects in SciFi, it passed various planets. Thus; it was on the same plane. Nyeaah

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Drat.

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