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
The reason the atmosphere doesn’t fly off into space is because of gravity, which isn’t caused by the metal in the core of the earth but by mass. The more massive something is the more gravitational pull it has. Keep in mind the sun technically has to solid core but the fact that it’s something like 90% of the solar systems total mass keeps everything in orbit. Also solar radiation isn’t that bad when you consider the sheer distance between earth and the sun, sure you’d get cooked if you went to mercury but the moon? Not so much, the temps only go up to a couple hundred degrees, and can be compensated for by cooling systems. As for the integrity of aluminum, yeah it’s pretty strong, everything from submarines to fighter jets have been made from the stuff, hell F-22s are partly plastic. Also the Apollo capsule was only pressurized up to an equivalent altitude of 20,000ft so the designers did actually have a concern but it was later found to be unfounded. I don’t know where you are getting the 5000 degrees from as I don’t think there is anywhere in either earth or lunar space where temps get that high.