This is what I've learned so far about where we are in the Milky Way:
1. We are about 26,000 light years from the Galactic Center.
2. We are about 64 light years north of the Galactic Equator (an average based on numerous estimates).
3. The Solar System subtends an angle of only 0.14 degrees from the Galactic Center (tan-1 64/26,000 - less than the portion of the sky occupied by the Sun as seen from Earth - which is about 0.53 degrees). Illustrations typically greatly exaggerate this angle in their depiction of our sinusoidal path around the Milky Way.
4. We complete one revolution around the Galactic Center once every ~220 million years, with a "vertical period" of about 66 million years (i.e., we pass through the Galactic midplane once every ~33 million years).
5. The sun and planets passed through the Galactic Equator about 2-3 million years ago.
6. Starting with the Earth's North Pole as "up" (or North Celestial Pole), the earth is tilted at 23.4 degrees away from the North Ecliptic Pole, or the sun's axis of rotation.
7. Given this initial frame of reference, the Earth is rotating counterclockwise, and is also revolving counterclockwise in its orbit around the Sun, which is in turn rotating counterclockwise.
8. Starting with the Earth's North Pole as "up," i.e., pointing towards Polaris (the North Star), the Earth is tilted at an angle of 23.4° relative to the Sun's axis of rotation.
9. The Ecliptic Plane, the imaginary disk perpendicular to the Sun's axis of rotation, along which the planets move with relatively small inclinations (except Pluto), is tilted at an angle of about 60.19 degrees above (north of) the Galactic Equator, and is "leaning forward" (although some illustrations show it “leaning back”) in its CLOCKWISE movement around the Milky Way.
10. The orientation of the Earth's axis of rotation relative to the galactic equator is about 27.14 degrees (Galactic Latitude). This is not easy to calculate. You need something called spherical trigonometry to get the answer.
11. The Ecliptic Plane is nearly aligned with the Galactic Center - it's only about 5 degrees away from being bang-on.
It's very difficult to wrap your head around all these different points of view, let alone come up with a decent illustration for all these various perspectives and scales. I'm attaching one that might help.
1. We are about 26,000 light years from the Galactic Center.
2. We are about 64 light years north of the Galactic Equator (an average based on numerous estimates).
3. The Solar System subtends an angle of only 0.14 degrees from the Galactic Center (tan-1 64/26,000 - less than the portion of the sky occupied by the Sun as seen from Earth - which is about 0.53 degrees). Illustrations typically greatly exaggerate this angle in their depiction of our sinusoidal path around the Milky Way.
4. We complete one revolution around the Galactic Center once every ~220 million years, with a "vertical period" of about 66 million years (i.e., we pass through the Galactic midplane once every ~33 million years).
5. The sun and planets passed through the Galactic Equator about 2-3 million years ago.
6. Starting with the Earth's North Pole as "up" (or North Celestial Pole), the earth is tilted at 23.4 degrees away from the North Ecliptic Pole, or the sun's axis of rotation.
7. Given this initial frame of reference, the Earth is rotating counterclockwise, and is also revolving counterclockwise in its orbit around the Sun, which is in turn rotating counterclockwise.
8. Starting with the Earth's North Pole as "up," i.e., pointing towards Polaris (the North Star), the Earth is tilted at an angle of 23.4° relative to the Sun's axis of rotation.
9. The Ecliptic Plane, the imaginary disk perpendicular to the Sun's axis of rotation, along which the planets move with relatively small inclinations (except Pluto), is tilted at an angle of about 60.19 degrees above (north of) the Galactic Equator, and is "leaning forward" (although some illustrations show it “leaning back”) in its CLOCKWISE movement around the Milky Way.
10. The orientation of the Earth's axis of rotation relative to the galactic equator is about 27.14 degrees (Galactic Latitude). This is not easy to calculate. You need something called spherical trigonometry to get the answer.
11. The Ecliptic Plane is nearly aligned with the Galactic Center - it's only about 5 degrees away from being bang-on.
It's very difficult to wrap your head around all these different points of view, let alone come up with a decent illustration for all these various perspectives and scales. I'm attaching one that might help.
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