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I assume its part c you are having a problem with. 

Someone will correct me if i have got it wrong as celestial mechanics is not my forte. 

The reason the moons orbit appears to move and the stars dont is because not only is the earth spinning which gives the stars their apparent motion but the moon is moving relative to the earth. so you have the earths rotation of aprox 24 hours added to that the moons orbital rotation of aprox 28 days if the moon was not orbiting but staying in a stationary position relative to earth it would follow the same path as the stars adjusting with seasonal tilt. I think

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I assume its part c you are having a problem with. 

Someone will correct me if i have got it wrong as celestial mechanics is not my forte. 

The reason the moons orbit appears to move and the stars dont is because not only is the earth spinning which gives the stars their apparent motion but the moon is moving relative to the earth. so you have the earths rotation of aprox 24 hours added to that the moons orbital rotation of aprox 28 days if the moon was not orbiting but staying in a stationary position relative to earth it would follow the same path as the stars adjusting with seasonal tilt. I think

Quite right, as our earth spins, the stars appear to move, but since the moon is earths satellite, we see it at different phases, full moon at its highest new moon when we cant see it at all

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   Since the best detailed telescopic views happen when the Moon is highest in the sky, check when it rises - the farther east it rises, the higher in the sky will be its overhead path. When it rises in the SW (northern hemisphere) its path across the sky will be very low and not suitable for good telescopic views then when its path is much higher. By the way, if the path across the sky is low, it will gain height to a more favorable observing path in a few days.

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Hi

how could i know the height/loction of the moon in the sky - 

a. in a specific phase of the moon?

b. at a certain time (at sunrise, at sunset...)?

c. why the moon change the height?

thanks

You can work it out by hand.

I have a spreadsheet that I have done as well (Excel) if you would like it, the link is http://stargazerslounge.com/topic/84252-excel-spreadsheet-moon-and-celestial-data/

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By the way: If it's really good views of craters that is your thing you should aim your scope towards the terminator. This is the line between the lit and unlit surfaces of the moon. Since the sunlight is hitting the moon at a very shallow angle there will be dramatic shadows cast which will not only make the crater walls more distinct, but a decent scope & eyepiece can even give an illusion of the full 3D effect. You'll want to reach out and brush the dust out of the way so you can get a better look at the bedrock! In full daylight areas all of these features are completely washed out and invisible although the Mare (seas) and ejecta rays are more easily made out.

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One useful fact to remember is that when the moon is "full" it is approximately on the opposite side of the Earth to the Sun. Sometimes so exact that it's actually in Earth's shadow - a lunar eclipse occurs.

More often than not it passes above or below Earth's shadow on it's journey round us. It takes about 28 days to orbit and so successive full moons are about a month apart. No coincidence, the Moon was an important factor in early time keeping and it's motion is at the origin of early calendars.

So making a quantum leap, ignoring what causes the seasonal variations in the Sun's height in the sky, one rule of thumb for the Moons position at certain phases is that in summer, when the Sun arches high in the sky a Full Moon will not rise very high. It's opposite the Sun so sits in the part of the sky where the Sun would be in winter. Even at midnight it's quite low.

The opposite occurs in winter. The Sun sits low at midday but a Full Moon rides high at night! Once the mechanics click into place you see that around the equinoxes when the Sun is midway between Summer and winter the Moon too will be "middling" .A full moon will trace almost the same path across the night sky as the Sun did during the day. In spring when the sun is "heading south" the subsequent Full Moons will be "heading north", getting higher in the sky each month. 

At the Spring equinox when the Sun is at the mid point of it's seasonal path (the Ecliptic) the Moon still passes through the high and low points each month but in Spring it's the first quarter phase that rides high in the evening sky and last Quarter rides low in the early morning. In Autumn this is reversed. The first quarter moon rides low in the evening but the last quarter rides high.

So where the moon is at any one time depends on the season and where the Moon is in it's orbit. The moon's orbit isn't perfectly circular nor perfectly in line with the ecliptic. So the fine detail is very complex to work out. 

Sorry for rambling, I couldn't sleep so got up an hour early for work :)

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.... In spring when the sun is "heading south" the subsequent Full Moons will be "heading north", getting higher in the sky each month.

Sorry, just read this back now I'm awake.

Should read "in autumn, when the sun is heading south"

Sent from my HTC One using Tapatalk

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