Does the Earth really orbit the Sun?

[Pontiuth Pilate]

In the sense that the Sun is one focus of the ellipse traced by the Earth, I mean.

Because I'm pretty sure that the Earth's orbit is an ellipse around the center of mass of the solar system.

That can't possibly be the center of the Sun, can it? In fact given the masses of Jupiter and Saturn, is it even a correct approximation to say that the center of mass of the solar system is in the Sun?

Damn these superstitious heliocentrist bastards

 

[The Last Conformist]

Some back-of-the-envelope calculations would seem to indicate that the Solar System's CoG is just outside the Sun's surface.

 

[Warman17]

Jupiter + Saturn = 317.8 Earths + 95.162 Earths = 412.962

Sun = 332,950 Earths

So Jup + Sat = .124% the mass of the sun. SO maybe it's not the exact center of the sun, but it's still in there.

 

[bed_head7]

The center of mass of the solar system is generally just over a tenth of a solar radius outside of the sun, so treating the sun as the exact center of mass is not strictly correct. However, the difference between the center of the sun and the center of mass is negligible when making calculations. Also despite Jupiter being much more massive than the Earth, making it seem relatively large, the mass of the sun comprises 99.85% of the mass of the solar system, or something absurd like that. So it is a pretty decent approximation.

 

[Pontiuth Pilate]

Ha! Wiki says I'm right!

the Sun itself orbits the center of mass of the solar system, which is located nearly a solar radius away from the center of the Sun mostly because of the large mass of Jupiter.

That is approximately 696,000 km from the center of the Sun, whereas the radius of the Earth's orbit at aphelion is 152,097,701 km. So the estimate is off by as much as half a percent! That is very significant if you want to land something on the Moon or Mars.

I bet the real scientists (aka NASA) don't use the center-of-the-sun approximation. Or wait, maybe that's why we keep missing Mars.

 

[Perfection]

Of course the whole idea of orbiting around in an elliptical path is merely an approximization. Earth's path is effected by all the other bodies in the universe and it behaves in a non-elliptical path.

 

[King Flevance]

Or wait, maybe that's why we keep missing Mars.

ROFL

 

[Eukaryote]

The sun is like 98.5% of the mass of the solar system so we're going around just outside the center.

 

[Abaddon]

Not forgetting Earth tilt, wobble and roll it does now and again just to confuse climatologists.

Everythings simplified at school.. and your never corrected unless you do the specific study.


Reminds me of my first lecture in uni.

"So, yeah- most things you have been taught, arn't actually true"

 

[warpus]

"The earth orbits the sun" is just an approximation of what actually happens.

It's technically wrong, but right enough for every-day conversation.

 

[Red Threat]

No, the Sun orbits the Earth. The Bible says this.

 

[Dreadnought]

Little kids wouldn't understand about the difference, so its said the sun is in the middle.

 

[Abaddon]

No, the Sun orbits the Earth. The Bible says this.

The bible says a lot of things. Whats to say its all true? Do you actually believe this one?

 

[Bluemofia]

Little kids wouldn't understand about the difference, so its said the sun is in the middle.

So true.

My teachers denyed the existence of negative numbers in 2nd and 3rd grade. I got the last laugh though.

 

[general_kill]

Physics is all about perspectives.

Ever hear of the theory that you age slower if you are traveling at a fast speed? Well its not completely true. Let's say there were two twin sisters. 1 sister stays on Earth. The other sister goes on a super fast spaceship in a journey to another galaxy. From the spaceship sister's perspective, the voyage lasted 1 year. But from the other sister's perspective, 40 years might have passed. It's all relativity.

When we look up at the sky, we sees millions of stars moving across it as if they were orbiting us. Relative to Earth, they are orbiting us. Relative to the sun, Earth is orbiting it. Relative to the galaxy, well you get the idea.

My physics teacher made a much more convincing argument when I asked him these questions.

 

[warpus]

^ It is all relative, but when you ask "What does the Earth orbit, relative to the rest of the Solar System?", you have to take the frame of reference of the centre of gravity of the entire solar system... and that's what the Earth orbits, technically.

The Earth also orbits the centre of gravity of the Milky Way, but that reference point is almost never assumed.

 

[ybbor]

Of course the whole idea of orbiting around in an elliptical path is merely an approximization. Earth's path is effected by all the other bodies in the universe and it behaves in a non-elliptical path.

unlike the updating of Eat Poop you Cat which is only affected by how lazy Perfection is.

ON-topic: Why do the planets follow an eleipitcal orbit?

The bible says a lot of things. Whats to say its all true? Do you actually believe this one?

you realize he's joking right? nowhere in the Bible does it say the Sun orbits the earth

 

[Pontiuth Pilate]

Why do the planets follow an eleipitcal orbit?

Imagine you plunk a planet down at some distance x from the Sun and give it some velocity v tangential to a perfectly circular orbit. For each x, there is only one v that results in a stable circular orbit. All other v's which result in stable orbits produce ellipses. Initial v's which aren't stable can be too slow (the planet falls into the sun) or too fast (hyperbola, the planet swings round the star and never comes back)

Also turns out that if you take a perfectly circular orbit and disrupt it with a gravitational force from another source (like a nearby planet) you will usually end up with an ellipse.

Basically a circle is too "perfect" or "exact" of an orbit to not eventually degrade.

 

[ironduck]

you realize he's joking right? nowhere in the Bible does it say the Sun orbits the earth

It does say stuff that points to it:

5 The sun rises and the sun sets,
and hurries back to where it rises.

5 He set the earth on its foundations;
it can never be moved.

So the earth doesn't move. And yet the sun rises and sets and hurries back again. If the sun isn't orbiting the earth it sure is making some wicked motions

 

[Cheezy the Wiz]

i hope someday people will realize THE BIBLE IS ALLEGORICAL. its doesnt mean literally "the earth does not move" nor does it mean, literally," the earth was created in seven days" i reference the seven days thing because its hte first thing that came to mind. You have to take the Bible in perspective, just because a phrase means something literally in our manner of thinking doesnt mean that that's what God or whoever was writing this ( through divine inspiration though) means. you know what, new thread time