<p>The orbits of the planets are coplanar (in the same plane) because supposedly during the Solar System's formation, the planets formed out of a disk of dust (ha, ha)  which surrounded the Sun. Because it was a <strong><em>disk</em></strong>, all in one plane, all of the planets formed in that one lousy plane as well.</p>

<p>Single rings and disks are common in astronomy. Jupiter's moons are coplanar too.</p>

<p>The common explanation is that orbits are unstable and they all eventually tend to get into the same plane and stay there. Wouldn't it be fun to have a planet orbiting the Sun at a right angle to the other planet's orbits? You'd never know when the damn thing's going to hit what. </p>

CC BY-SA 3.0
2016-01-02T06:52:18.520Z
+1 for the explanation. Yes, right angled path would cause a massacre.
ni8mr
CC BY-SA 3.0
2016-01-04T11:31:23.130Z
@barrycarter: Yeah, well, Jupiter is rumored to be on the lookout for those.
Ricky
CC BY-SA 3.0
2016-01-05T06:22:19.197Z
Only 8 of Jupiter's moons are coplanar: the 4 Galilean moons and the 4 inferior moons.  The other ~60 (all superior to Callisto) are at least 25 degrees out of plane.  Their eccentricities are rather large, too: >0.2 for most of them.
Bill N
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2016-01-05T06:38:05.917Z
@BillN: What's 25 degrees among friends. It's still in keeping with the general idea. 80 or 90 would be something.
Ricky
CC BY-SA 3.0
2016-01-05T06:45:37.287Z
@Ricky: Have you ever been on a boat tilting at 25 degrees or tried to climb a 25 degree inclined plane? It's a pretty dramatic angle. Pluto is "only" 17 degrees.
Bill N
CC BY-SA 3.0
2016-01-05T06:59:18.517Z
@BillN: 1. No. 2. Yes. Dramatic, not so much. And anyway, between Jupiter's gravity and that of the Sun, they will eventually see reason and line up properly.
Ricky
CC BY-SA 3.0
2016-01-02T06:43:06.730Z
2016-01-02T06:43:06.730Z
Ricky
<p>I am going to ask an odd question, It is: In most of the images of our solar system we see that the planets are arranged in  a straight line. As the paths of the planets are elliptical, could it be possible for planets be arranged other than in straight line (a bit up and down) ?</p>

CC BY-SA 3.0
2016-01-02T05:08:39.660Z
I mean, when we place them side by side, every image place them on a straight line. Are they really in a straight line like it ?
ni8mr
CC BY-SA 3.0
2016-01-02T05:12:18.347Z
Do you mean are planets always positioned like [this?](http://sciencequestionswithsurprisinganswers.org/images/planets.png)
This Play Name
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2016-01-02T05:19:37.603Z
@ThisPlayName yes !
ni8mr
CC BY-SA 3.0
2016-01-02T06:29:18.700Z
@barrycarter I know about this. What i am asking is that, is Earth is above Mars (taking case of position) or something like that ? Or they are perfectly in a straight line ?   It is kind of silly question though, cause it doesn't have any importance. I am just curious.
ni8mr
CC BY-SA 3.0
2016-01-03T01:11:26.137Z
Pluto (though no longer a planet) is the most tilted off the plane.  Mercury the 2nd most.    https://en.wikipedia.org/wiki/Orbital_inclination   and, not really what you asked, but related and a fun little video:  https://www.youtube.com/watch?v=tmNXKqeUtJM
userLTK
CC BY-SA 3.0
2016-01-03T13:30:00.903Z
It seems you are reffering to what we know as the "ecplitic". This is the plain where the orbits of all the planets usually are. Of course they are never in a perfect "straight" line. If you for example look at mars (https://en.wikipedia.org/wiki/Mars), you can see under "Inclination" how far away its orbit is from the ecliptic.
RononDex
CC BY-SA 3.0
2016-01-02T05:06:22.577Z
What do you mean by straight line?
This Play Name
<solar-system><planet>
Alignments of planets
ni8mr
# Alignments of planets

(Asked by: username_0 on 2016-01-02)

I am going to ask an odd question, It is: In most of the images of our solar system we see that the planets are arranged in a straight line. As the paths of the planets are elliptical, could it be possible for planets be arranged other than in straight line (a bit up and down) ?

**Tags:** solar-system, planet
> **Comments:**
> **username_1**: What do you mean by straight line?  
> **username_0**: I mean, when we place them side by side, every image place them on a straight line. Are they really in a straight line like it ?  
> **username_1**: Do you mean are planets always positioned like [this?](http://sciencequestionswithsurprisinganswers.org/images/planets.png)  
> **username_0**: @ThisPlayName yes !  
> **username_0**: @barrycarter I know about this. What i am asking is that, is Earth is above Mars (taking case of position) or something like that ? Or they are perfectly in a straight line ?   It is kind of silly question though, cause it doesn't have any importance. I am just curious.  
> **username_2**: Pluto (though no longer a planet) is the most tilted off the plane.  Mercury the 2nd most.    https://en.wikipedia.org/wiki/Orbital_inclination   and, not really what you asked, but related and a fun little video:  https://www.youtube.com/watch?v=tmNXKqeUtJM  
> **username_3**: It seems you are reffering to what we know as the "ecplitic". This is the plain where the orbits of all the planets usually are. Of course they are never in a perfect "straight" line. If you for example look at mars (https://en.wikipedia.org/wiki/Mars), you can see under "Inclination" how far away its orbit is from the ecliptic.  

---

## 1 answers

### Answer by username_4 on 2016-01-02. Score: 1

The orbits of the planets are coplanar (in the same plane) because supposedly during the Solar System's formation, the planets formed out of a disk of dust (ha, ha) which surrounded the Sun. Because it was a ***disk***, all in one plane, all of the planets formed in that one lousy plane as well.

Single rings and disks are common in astronomy. Jupiter's moons are coplanar too.

The common explanation is that orbits are unstable and they all eventually tend to get into the same plane and stay there. Wouldn't it be fun to have a planet orbiting the Sun at a right angle to the other planet's orbits? You'd never know when the damn thing's going to hit what.

> **Comments:**
> **username_0**: +1 for the explanation. Yes, right angled path would cause a massacre.  
> **username_4**: @barrycarter: Yeah, well, Jupiter is rumored to be on the lookout for those.  
> **username_5**: Only 8 of Jupiter's moons are coplanar: the 4 Galilean moons and the 4 inferior moons.  The other ~60 (all superior to Callisto) are at least 25 degrees out of plane.  Their eccentricities are rather large, too: >0.2 for most of them.  
> **username_4**: @BillN: What's 25 degrees among friends. It's still in keeping with the general idea. 80 or 90 would be something.  
> **username_5**: @Ricky: Have you ever been on a boat tilting at 25 degrees or tried to climb a 25 degree inclined plane? It's a pretty dramatic angle. Pluto is "only" 17 degrees.  
> **username_4**: @BillN: 1. No. 2. Yes. Dramatic, not so much. And anyway, between Jupiter's gravity and that of the Sun, they will eventually see reason and line up properly.  

---

