Physics/science doubt
- Thread starter desihawk
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It’s always been my understanding that distance of the sun is the only variable. I always assumed mass was irrelevant as mass, on Earth, has no impact on gravity.
yes makes sense if we imagine everything runs like pendulum newtonian model but if you let's say swap earth and jupiter and exchange their speeds, does that mean everything stays stable?
I'm not an astrophysicist but I have never heard the idea that the mass of an object has much to do with it's orbital period.
Me either. Where’s @fsu1jreed?
I would venture to say that if you just swapped Earth and Jupiter, and their speeds remained constant, Jupiter would orbit at 365 days instead of Earth.
so jupiter won't do something to alter the orbit of mercury or some such shit?
Wikipedia says this
It does have mass in the equation but it specifies the mass of the more massive body. So in our case that mass is the sun. So it sounds to me that while the mass of the object being orbited does influence things, the mass of the object doing the orbiting actually does not matter.
It does have mass in the equation but it specifies the mass of the more massive body. So in our case that mass is the sun. So it sounds to me that while the mass of the object being orbited does influence things, the mass of the object doing the orbiting actually does not matter.
Initially.
But it would crash into the sun fairly soon.
This thread is revealing a lot of loony thinking.
Based on a few minutes worth of research my guess is that if Jupiter and the earth were to suddenly switch locations, other than the obvious effects of all life on earth dying out, it seems to me that Jupiter would potentially capture Venus (but not mercury) and create a moon.
I am basing this on Jupiter's relative gravitational sphere's of influence being greater than the distance between the Earth and Venus when passing by one another.
That said I am also approaching this whole thing with very limited knowledge and education on the matter. Placing Jupiter closer to the sun for instance could decrease it's gravitational sphere of influence because the sun being nearer would be a stronger force than in it's current location.
And that's assuming that I'm even using these numbers correctly in the first place.
What would cause the orbit of Jupiter to decay to the point of impacting the sun?
Yes, mass matters.
The orbital speed has to balance the mass.
Jupiter in Earth's orbit and at Earth's orbital speed, isn't moving fast enough to balance the greatly increased gravitational attraction between Jupiter and the sun. Hence, it would spiral into the sun.
Meanwhile, Earth in Jupiter's orbit and at Jupiter's orbital speed would spiral out of the solar system (or maybe to an orbit much farther out), because that speed is way too fast to balance the reduced gravitational attraction.
The orbital speed has to balance the mass.
Jupiter in Earth's orbit and at Earth's orbital speed, isn't moving fast enough to balance the greatly increased gravitational attraction between Jupiter and the sun. Hence, it would spiral into the sun.
Meanwhile, Earth in Jupiter's orbit and at Jupiter's orbital speed would spiral out of the solar system (or maybe to an orbit much farther out), because that speed is way too fast to balance the reduced gravitational attraction.
The gravitational attraction between Jupiter and sun would be orders of magnitude greater than that between Earth and the sun.
What you write makes intuitive sense. To reconcile this with the diagram in OP, it would mean that the planets are all beautifully/precisely aligned to make it appear that mass is irrelevant when it comes to orbits. However, this is only an appearance because any changes actually will result in instability. Yes?
Why don’t we just ask our resident @JupiterHawk
Basically anything that didn't fit that line would have fallen into the sun or would have been flung further out during the early evolution of the solar system. For the most part, we are left with the objects that achieved gravitational balance.
Is it necessarily the case that everything in a stable orbit align that way? Pretty sure the answer is yes, but my brain isn't working well enough at the moment to prove it.
Did WWJD just admit that the universe is 'fine tuned'? That is something the Jesus really would do.
Got hit by Hurricane Sarah, which knocked out power and internet has been on/off since then. What really sucks is that my air mattress went flat (just had another skin graft 2 days before it hit) so I went to lay on my regular bed, but during that process the skin graft was sheered off.
So, I'm going to have another skin graft surgery next month and I just bought a Propane & Gas generator (which broke me), so this never happens again. I actually should have bought one years ago when I bought this house. So that one is kind of on me.
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Our solar system is actually pretty unique in that most other solar systems we have found have a gas giant that is very close to the sun. That's one of many unique features of our solar system that allow life to exist.
So to answer your question, no, mass is not a factor in determining how far planets are from the sun. The graph looks like it is on a logarithmic scale which is why the planets seem like they are on a straight line.
So to answer your question, no, mass is not a factor in determining how far planets are from the sun. The graph looks like it is on a logarithmic scale which is why the planets seem like they are on a straight line.
Present thinking is that Jupiter (with a couple of other large proto-planets formed very close to the sun and then migrated outward.......it explains the Late Heavy Bombardment (which has been a mystery to scientists).
New date for 'Late Heavy Bombardment' may change life's timeline on Earth
Most researchers think the Late Heavy Bombardment was caused by the giant planets moving around, orbiting closer to and farther from the sun and pushing lots of smaller solar system objects like asteroids along with them.
Back when physics was practices by physicists and not mathematicians.
Pfffft. Tesla was a hack who got his jollies playing with dime store sparklers.
Actually, with current technology is space it's very hard to detect the smaller planets (such as Earth).....that will all change when the James Webb telescope is launched next year.
NASA Announces New James Webb Space Telescope Target Launch Date
I assume this is satire, but I've never seen him/her before.
Just for the record, distance from the center of mass of the solar system - the barycenter - does affect velocities so that Mercury's orbital velocity is greater than that of Venus and Venus' velocity is greater than that of the Earth, and so on out to...Pluto? 
Swapping Jupiter and Earth as they exist right now would have Jupiter crawling around the Sun at a speed that's about half that of the Earth...so a 700+ day year.
Swapping Jupiter and Earth as they exist right now would have Jupiter crawling around the Sun at a speed that's about half that of the Earth...so a 700+ day year.
Here's the answer with the math included
How does mass affect orbital speed?
In my University Physics class we had a question on this very thing on the final test..........no way could I begin to try and answer it now.
How does mass affect orbital speed?
In my University Physics class we had a question on this very thing on the final test..........no way could I begin to try and answer it now.
You aren't wrong, but we know that most extra solar systems tend to have a gas giant much closer to the star than we do in ours.
Oh, I agree with you, but a large number of said planets orbit around young stars in young solar systems, before the planets begin to migrate outward.
Young Giant Planet Offers Clues to Formation of Exotic Worlds
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