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I know that there is nothing north, south, east or west in space there is no reference by which you can tell if apparent north is up, down, left or right.

But as I understand that all planets in the solar system are moving in a certain direction in a helix and not revolving in one plane.

See this video : https://www.youtube.com/shorts/Yr6-KHx_2fM

Now say if we consider that direction to be our reference, then what's the orientation of our earth, where does our north, south, east and west lies?

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    $\begingroup$ The linked video may be complete garbage. It is very similar to the garbage produced by DJ Sadhu. See the review by Phil Plait. Others give similarly negative reviews. $\endgroup$ Commented Dec 23, 2022 at 11:03
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    $\begingroup$ The video is mostly crap, the author is just increasing the y value of the of the solar system's position at an arbitrary rate. This orientation doesn't reflect the planet's orbit orientation as the Sun moves around the Galaxy, nor in relation to other galaxies. This link has a better representation: forbes.com/sites/startswithabang/2018/08/30/… $\endgroup$ Commented Dec 24, 2022 at 4:01

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The linked video assumes that solar system is moving in a certain direction, but does not define the reference frame chosen to measure the movement. If another reference frame had been chosen, another set of helices would have been generated.

There is no privileged inertial reference frame in the universe. The laws of physics work equally well no matter which “stationary” inertial reference frame is chosen. The solar system is not moving “in a certain direction”.

Do you want to orient the Earth in relation to its position and velocity in the Milky Way? You could consider the galactic center as the center of your inertial reference frame. The direction to the center of the Milky Way is the “teapot” group in Sagitarius.

enter image description here

enter image description here https://www.physicsforums.com/threads/orientation-of-the-earth-sun-and-solar-system-in-the-milky-way.888643

If you want a “seat of the pants” orientation, wait till midnight in July when Scorpius is above the southern horizon. Find “the teapot”. The galactic center is at the end of its spout. Polaris (North Star) will be high in the sky, behind you. If conditions are good, the Milky Way will run from 11 o’clock to 5 o’clock, through the galactic center at the spout of the “teapot”. The Earth’s velocity vector will be pointing towards 11 o’clock, 90* across the heavens from the galactic center. That’s where we are all going.

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  • $\begingroup$ now I am confused, lets say we consider 2 points A and B. Solar system travels from A to B in some time t in a helix. If this straight line AB is considered we have got a direction. Now based on this direction what's the orientation of Earth? $\endgroup$ Commented Dec 23, 2022 at 7:38
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    $\begingroup$ @Himanshuman, the issue is the placement of A and B, are they with respect to the nearby stars, the galactic core, our galactic neighbors or other more ambiguous references. Recommend an edit to the question to make it specific to the centre of the milky way since that is probably produces an answer that has some degree of meaning. $\endgroup$ Commented Dec 23, 2022 at 7:58

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