We are told that we only have tides in the oceans and seas because of the moon so why do we only see the moon once a day but we have two tides?
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The tides are caused by a wave that is caused by the moons orbit causing shifts in its relative gravitational intensity ( newtonian inverse square law) , creating a sinusoidal wave in the earths oceans. Because the moon orbits the earth in about 24 hrs, the moon is directly overhead and directly under us in 12 hr ( aprx) intervals. The moon is in line with either horizon at 12 hr (aprx) intervals as well. Thus the moon is at a relative apogee/ perogee relative to the surface of the sea in 6 hr intervals, each associated with a high/ low. An idealized example- at 12 noon moon is overhead- high tide. At 6pm moon is on western horizon ( low tide) at midnight it below- high tide, at 6 am at eastern horizon ( low tide) and at noon its high tide again. Thus two highs and two lows in a 24 hr period.
Due to eliptical orbits and the orbital period being not exactly 24 hrs the tide time shifts with the day. Additionally the sun has an influece on tide as well- thus the amplitude of the tide is variable and correlated with moon phase ( spring vs neap tides). Furthermore, underwater topography can have a profound complicating effect, especially due to the venturi effect.
Yea, the moon's gravity pulls on our oceans and moves them (quadrillion tons of water), yet clouds and atmospheric vapor doesn't get pulled into space. Man people can't think. Thanks for the explanation though....lol
Add to that the emptiness of space, with zero pressure, how the atmosphere of the Earth isn't stripped away in a nano-second.
And gravity, because we live on a molton ball of iron, yet jupiter and saturn have gravity but are gas giants. Let me repeat....GAS giants. No iron ball.
Yea, and comets are broken up by the sun's radiation melting their outer shell and spewing debris making a comet "tail" but saturn and jupiter don't have tails and are 100% gas (with no iron ball)...
And that sun produces radiation at such a high level that our boys rode in an aluminum foil cage and didn't get cooked for 6days, nor did their cage explode from the pressure difference of zero atmospheric pressure in space, cuz, you know aluminum is some strong stuff.
But yea, the van allen belt is radiation and temperatures are up to 5000 degrees but you know that aluminum foil reflects that heat and it's all good.
LOL
Jupiter and the gas giants have solid cores, larger than all of earth. That provide the dense mass needed to keep their gas from floating away. The sun is also mostly gas, and by your reasoning then should also dissipate into space.
Also the van allen/ ionosphere does a hell of allot to keep out atmosphere put.
The reason why the atmosphere ( which do have a tide) isnt as effected by tides as much as the oceans is the fact that gravitational pull is proportional to the masses involved. Therefore the earth oceans have a stronger gravitational pull than the atmosphere. Also due to inverse square law. As the distance between two gravitatioal bodies increse the gravitational force decreases exponentially. So that means that the earths gravitational pull on the atmosphere, oaceans and us is way higer than that of the sun, even though the sun is way bigger, and why we all dont float away.
The tides are a wave. The oceans are not being pulled straigt up and down, they are more sloshing back and forth in rythem with the sun and moons gravitaional influence. Almost like how if you put a glass of water on a table and than tilt the table back and forth sligtly, it would begin to slosh back and forth creating a wave.
Similarly as the reltive strength of the moon and suns gravitational pull rythmically ocillates with the elipical orbit of the moon and rotation of the earth, ( inverse sqare law) it creates just enough force to cause the oceans to slosh a tiny bit - the tides. If this was not true than why are tidal predictions perfecly accurate? Im a captain and use them daily wit zero discrepancy.
Also the tide is highly influenced by ocean topography. In the open ocean the tidal range only a few inches. It is only due to the venturi effect ( the velocity of a fluid increases as it flows through a constriction) that they become pronounced near shore. Thats why the tides in a fjord can be 15 ft + and only a couple feet on a broad open coast.