Just wondering

[leee (Thomas)]

1. Is it simply just a mathematical (orbital) coincidence , that only one side of the moon is ever visible to us. ? I suppose that will change in eons to come as one of us slows down ?

2. I heard it proposed - If the earth did not have a molten core - earth would not have any gravity. True ?

3.Why do we rotate around the sun in approximately the same 'flat' orbit ? (GR makes space three dimensional so why not a 3D. kind of multi orbit rotation ?)


Hope these questions are not to elementary or stupid

[Allan_L (Allan)]

Re: 2 False

Newton's law of universal gravitation states that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers

So the mass of the Earth is what determines gravity.
Planets that have no molten core still have gravity.

The molten core is what effects our magnetic field, which protects us from the radiation from the sun, as I understand it

[Allan_L (Allan)]

Re: 3
Not only is our orbit "flat" around the sun, but the majority of our solar system is on the same flat plane.
That's why they tend to follow the same apparent path (as observed from the Earth) and this is called the Ecliptic

Why? It’s mainly because, long ago, before there was a solar system as we know it today, there was a vast cloud of gas and dust in space. This cloud was spinning, and, as it spun, it flattened out. Our sun formed in the center of this cloud, and the major planets and most other solar system objects formed in the flat disk surrounding the sun.

[Allan_L (Allan)]

Re: 1 Good Question
The Moon is "Tidally locked" to the Earth which means it rotates (on its axis) at the same rate that it orbits the Earth.

The Moon was almost certainly not tidally locked when it first formed - at that time, it would have rotated at a faster speed, which meant that had any observer been on the early Earth, they could have seen all sides of the moon as it spun. However, the gravitational pull from the Earth - which like the tides due to the Moon, pulls on the side of the Moon closest to the earth more than the far side, resisted this faster rotation. This resistance due to the gravitational pull of the Earth gradually slowed down the faster spin of the Moon until the Moon was no longer rotating faster than it was orbiting. Once the Moon’s rotation had slowed so much that a single face was always facing the surface of the Earth, it had officially been tidally locked, and has stayed in this configuration ever since.

[Allan_L (Allan)]

Oh, and Welcome to IceInSpace Thomas

Keep asking questions

Where are you located?
You should try to join an observing group and see what there is to see out there.

[Rainmaker (Matt)]

Originally Posted by Allan_L

Re: 1 Good Question
The Moon is "Tidally locked" to the Earth which means it rotates (on its axis) at the same rate that it orbits the Earth.

Not only that, but eventually the Earth will slow to the point where the same side of the Earth will always face the Moon. I hope I am on the other side so I can still see some DSOs....

[Allan_L (Allan)]

Originally Posted by Rainmaker

Not only that, but eventually the Earth will slow to the point where the same side of the Earth will always face the Moon. I hope I am on the other side so I can still see some DSOs....

Good point

[doppler (Rick)]

And to add to 3 , most galaxies also rotate on a flat plane, not sure about the irregular galaxies though.

[xelasnave]

Something that is apparently happening is the Moon is moving away from the Earth.
We are currently able to see a total eclipse with both the Sun and the Moon appearing the same size ..in many years to come to we won't be able to do that ...because we will be dead.
But those alive then we see a Moon that appears smaller than we see it today so an eclipse will have the Moon only partially covering the Sun and I expect you will see the Moon with a very bright disk (the part of the Sun that will be visible).
I wonder how flat Earthers will explain that if such a crazy notion can make it into the future. It is amazing that anyone can belief the Earth is flat today. Still there are many who still believe such invariably because, unwisely, they take their particular holy book literally and given in USA some 20% of the population take their good book as entirely correct one wonders just how many flat Earthers exist in the USA...there are actually a few who believe that the Earth is the centre of the Universe in that, all there is, including the Sun, orbits the Earth. But that's what you must expect if you see your holy book as a complete authority on reality and indeed science.
I think if one looks at the path of the Earth thru space you may find its path follows a spiral course.
Alex

[leee (Thomas)]

thanks --all

[brian nordstrom (As avatar)]

The moon is 440x closer than the sun , but it's 440x smaller , that's why we get total solar eclipse's .

Brian.

[Renato1 (Renato)]

Originally Posted by xelasnave

Something that is apparently happening is the Moon is moving away from the Earth.
We are currently able to see a total eclipse with both the Sun and the Moon appearing the same size ..in many years to come to we won't be able to do that ...because we will be dead.
But those alive then we see a Moon that appears smaller than we see it today so an eclipse will have the Moon only partially covering the Sun and I expect you will see the Moon with a very bright disk (the part of the Sun that will be visible).
I wonder how flat Earthers will explain that if such a crazy notion can make it into the future. It is amazing that anyone can belief the Earth is flat today. Still there are many who still believe such invariably because, unwisely, they take their particular holy book literally and given in USA some 20% of the population take their good book as entirely correct one wonders just how many flat Earthers exist in the USA...there are actually a few who believe that the Earth is the centre of the Universe in that, all there is, including the Sun, orbits the Earth. But that's what you must expect if you see your holy book as a complete authority on reality and indeed science.
I think if one looks at the path of the Earth thru space you may find its path follows a spiral course.
Alex

The Bible doesn't say the earth is flat.
https://answersingenesis.org/astrono...ch-earth-flat/
Regards,
Renato

[Renato1 (Renato)]

Originally Posted by Rainmaker

Not only that, but eventually the Earth will slow to the point where the same side of the Earth will always face the Moon. I hope I am on the other side so I can still see some DSOs....

One could still see DSOs for a few days around New Moon time - though one would be pretty cheesed off if it was cloudy at that time.
Regards,
Renato

[raymo]

The point is moot, because the moon will leave us long before the Earth
ceases to rotate.
raymo

[xelasnave]

Originally Posted by Renato1

The Bible doesn't say the earth is flat.
https://answersingenesis.org/astrono...ch-earth-flat/
Regards,
Renato

It's a pity we can't discuss religion here but I think you may find there are folk who interpreted certain passages to suit that perspective ... any perspective in many cases...like the guy who carried around snakes when giving a service...anyways thanks for the link I will check its perspective.

Alex

[JA]

Live and let live

[xelasnave]

The preacher I am thinking about died sadly ...one of his snakes bit him.
Alex