Position of ecliptic in northern hemisphere

In summary, the conversation discusses the location and movement of the ecliptic, which is the apparent path of the sun. The speaker, who lives at 38 degrees latitude, noticed that the plane of the ecliptic was nearly overhead at the zenith, which they had not seen before. This can happen due to the tilt of the Earth's orbit and the different orbital times of the other planets. The speaker also mentions that the sun's position on the celestial equator and ecliptic can be predicted and varies throughout the year. They suggest going outside to observe the planets again, as they may not be as high in the sky as initially thought. The conversation ends with a summary of when the ecliptic will be closest to the
  • #1
mmwave
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I live in the northern hemisphere about 38 degrees latitude. Last week I noticed that the plane of the ecliptic defined by venus Mars and Jupiter (or was it saturn?) was nearly over head at the zenith. I don't remember seeing this in my past looks at the sky. Is this a once a year thing like the sun crossing the tropic of capricorn and I just never noticed?
 
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  • #2
The ecliptic is the apparent path of the sun. It is inclined to the celestail equatory by 23.5o. So the maximum angle between your vertical and the sun at your 38o latitude would be the difference: 38 - 23.5 = 4.5o. Less than 5 degrees, not very much.

Now the orbits of the planets are tilted realativ to the Earth's orbit, which means that their paths through the sky are not along the exact ecliptic but different circles. So they could very well at some time be 4.5 degrees north of the ecliptic and therefore overhead to you.

All of this can be predicted - google on ephimerides - but it doesn't happen at fixed times of the year; only the Earth goes around in a year, the other planets have their own orbital times, all different.
 
  • #3
At the equinox the sun is crossing the celestial equator, For you the celestial equator runs at 38deg above the horizon. This summer at the solstice the sun (at noon) will be at 38+23.5 or ~61deg (yes I dropped the .5, cus you are not EXACTLY at 38 so this is not an EXACT relationship). According to my globe at this time of the year the sun is about 3deg north of the equator (moving fast though!) So if you were to go outside and measure the length of the noon time shadow (Define noon as when the shortest Shadow is cast, not by your daylight savings time clock) with abit of trig you should find that the sun about ~40deg above the horizon. The sun by definition is on the ecliptic, if you are looking at the Midnight sky the ecliptic is located were the sun will be (or was) in 6 months, so at this time the ecliptic is about 3deg BELOW the equator, for you about 35deg above the horizon. Of the outer planets Saturn's orbit has the greatest angle with the ecliptic about 2.5 deg, so it seems to me at this time of the year the highest any of the outer planets could be in the midnight sky is something less then 40deg (This is for your 38N location) ... Humm.., Perhaps you need to step outside and look again. Are the planets really that high in the sky, looking at the meridian is rather uncomfortable if you are standing up. So if, when you are observing them, your neck is not craned to the breaking point the planets are not near the meridian!
 
  • #4
I'm going to assume that you made this observation sometime fairly soon after sunset.

The reason being that at this time of the year that's when the ecliptic will be the closest to the zenith in the Northern hemisphere (since the Earth is tilted to the ecliptic, and rotates, the ecliptic will change position with respect to the local zenith over the course of a day.) At your lattitude, it will pass within 15° of the zenith once a day (more precisely, at intervals of exactly one sidereal day) . During at the sumer solstice, it happens at noon. At the winter solstice, it happens at midnight. During the autumnal and vernal equinoxes it happens near sunrise and sunset respectively.
 
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FAQ: Position of ecliptic in northern hemisphere

What is the position of the ecliptic in the northern hemisphere?

The position of the ecliptic in the northern hemisphere refers to the path that the Sun appears to take across the sky as seen from Earth. It is tilted at an angle of approximately 23.5 degrees to the celestial equator.

How does the position of the ecliptic impact the seasons in the northern hemisphere?

The position of the ecliptic plays a crucial role in determining the seasons in the northern hemisphere. This tilt causes the Sun's rays to strike the Earth at different angles throughout the year, resulting in varying amounts of sunlight and temperature changes that create the four seasons.

What is the significance of the position of the ecliptic in relation to the zodiac signs?

The position of the ecliptic is closely tied to the zodiac signs, as it is the apparent path that the Sun takes through the constellations of the zodiac. The zodiac signs are based on this path and are used in astrology to determine a person's personality traits and future predictions.

Does the position of the ecliptic change over time in the northern hemisphere?

Yes, the position of the ecliptic does change over time in the northern hemisphere. This is due to the Earth's axial precession, which causes the Earth's axis to slowly shift in a circular motion. This movement results in a change in the angle of the tilt of the Earth's axis and therefore, the position of the ecliptic.

How does the position of the ecliptic impact the length of daylight hours in the northern hemisphere?

The position of the ecliptic has a direct effect on the length of daylight hours in the northern hemisphere. As the Earth orbits the Sun and the position of the ecliptic changes, the length of daylight hours also varies. This is why we have longer days in the summer and shorter days in the winter in the northern hemisphere.

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