Earth Doesn’t Orbit the Sun

Understanding gravity can sometimes be a bit of a balancing act, much like the fundamental laws of physics and how they inform what it is exactly that Earth orbits.

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[naturallyherb]

Some of the systems that best show a barycenter outside of a star body are binary stars: in the case of binary systems where two stars are about equal mass, the barycenter is a significant distance away from the star, meaning that the two stars appear to orbit around empty space, Alpha Centauri A-B being a very good example of this.

In the Solar System, Pluto-Charon is another very good example: because Charon is about half the size of Pluto, the two orbit a barycenter a significant distance outside of Pluto, and so such systems are visually striking at how their orbits look like.

[benedixtify]

I didn't know the center of mass of the sun and jupiter was actually outside the surface of the sun. That’s mind blowing.

[mathewbelemont]

Thank you for noticing my mass. Honestly it dosnt get enough credit

[wilsonli]

I didn't know that the barycenter between Jupiter and the Sun is slightly outside the sun. That's a pretty significant wobble! Considering how massive the Sun and Jupiter are, I would think that wobble has to have an impact on the orbits of the other planets, right?

[denimchicken]

Soooo yeah, it totally orbits the sun, just not a perfectly centered sun.

[SAOS]

generally in astronomy we don't say that objects orbit each other unless the barycenter is (always) outside the objects because it's simpler and we know how gravity works. so pluto and charon orbit each other but the earth and moon don't. it's pedantic and a bit clickbaity to suggest that the sun orbits the earth.

[canis]

I would argue that even though there is a shared center, we do orbit the Sun. It's volume encompasses this median point and like a hammer tosser the hammer is orbiting the tosser.

[DaellusKnights]

Way back in grade school, this whole concept was one of the principles that allowed me to mathematically prove that the whole world does, in fact, revolve around me. (Relative fuzzy logic from a 7th grader was a bit of an amusement back then) 😂🤣

[martinellis]

One point that should have been emphasized, perhaps someone makes the comment, is that the force you exert on the Earth is exactly the same as the force the Earth exerts on you. Like wise the force the Sun applies on the Earth is exactly the same as what the Earth applies to the Sun. It's the difference in mass only that governs how much each object moves as a result. This was covered at the start with the premise of every action has an equal but opposite reaction, but it is something that so many people get wrong it really worth emphasizing

[arandomperson]

I think a better way (weigh?) of thinking about the Earth-You system is that the Earth pulls down on you with a force equal to your weight, and you pull up on the Earth with a force equal to your weight. That upward force is distributed over the entire Earth so it's still negligible but this way of thinking about it highlights how the forces are exactly balanced.

[TraderDan]

If you think that’s a brain twister just Imagine the fact that we are not in a true circular orbit but actually chasing the sun in a spiral orbit while the sun moves around the edge of the galaxy

[zettagotbored]

When I was teaching Newton’s Third Law to my freshmen I informed them they were as powerful as literally everything else in the universe and they were pretty stunned. It was a really nice moment.
Also, random fact, if you were to isolate the sun-Jupiter system, the sun would orbit the barycenter with a velocity approximately equal to that of an unladen swallow.

[ikeekieeki]

"no other planet can yank the Sun around quite like Jupiter" 💀

[betula-pendula]

It is like a dance between the sun and its planets. Whirling around each other.

[I_love_space.]

This way of finding exoplanets is somewhat similar to how neptune was discovered because it pulling on uranus

[billammann]

This all sounds logical and reasonable to understand.

[fredworthmn]

Speaking as a lay person, to me the fact that the Earth orbits a point near the Sun seems more of a perspective indicating how long it takes the effects of the Sun’s gravity to influence the Earth. The Sun is also moving.

[Jolfgard]

They both gotta have a common center of gravity that should be somewhere in the sun. As Earth revolves around that common center, Earth not only technically but also practically revolves around the sun, just not around its center.

[alanfite]

Education is easy but learning is much harder.
Thanks for the knowledge in the video. 🌎🌍🌏

[MrTomtomtest]

That's actually the best kind of trivia.