I suspect that due to the random collision of gas clouds, or similar processes involved in the formation of solar systems, the rotation angle of a solar system - and of the star in the middle - is quite random.
Uranus.
It's because the Earth's axis is tilted. Therefore the plane of the equator is tilted (at about 23.5 degrees) away from the plane of the Earth's orbit. Therefore the celestial equator is tilted away from the ecliptic.
The Sun _does not_ tilt. The Earth orbits around the Sun, and the plane of the Earth's orbit around the Sun is called the "ecliptic". Compared to the ecliptic, the axis of the Earth's spin is "tilted" at a little over 23 degrees. It is this "tilt" of the Earth's spin that causes the seasons. So, WHY is the Earth's spin axis "tilted"? We may never know for sure, but at least some scientists believe that it may be related to the planetary collision that created the Moon.
Because - the Earth is tilted on its axis - by about 11 degrees. This means that, when the northern hemisphere is tilted towards the sun, the Southern Hemisphere is tilted away. This - combined with the position of the sun in its orbit around the Sun - creates our seasons.
The planet Uranus is tilted "on its side" about 98 degrees to the orbital plane. But all planets in our solar system have some tilt to the side, including Earth which tiles about 23 degrees. (Mercury's tilt is very small.)
Earth is tilted at 23.5 degrees from the plane of its orbit around the Sun.
Uranus.
The Earth's axis is tilted by about 23.5 degrees (more exactly 23 degrees, 26 minutes, 21.4119 seconds) with respect to the perpendicular to the plane of its orbit (the plane of the ecliptic)
Neither; the ecliptic, the plane of the Earth's orbit around the Sun, is inclined to the galactic plane by about 60 degrees. The galactic plane is easy to see; it is the path of the Milky Way across the night sky.
It's because the Earth's axis is tilted. Therefore the plane of the equator is tilted (at about 23.5 degrees) away from the plane of the Earth's orbit. Therefore the celestial equator is tilted away from the ecliptic.
It's because the Earth's axis is tilted. Therefore the plane of the equator is tilted (at about 23.5 degrees) away from the plane of the Earth's orbit. Therefore the celestial equator is tilted away from the ecliptic.
The Sun _does not_ tilt. The Earth orbits around the Sun, and the plane of the Earth's orbit around the Sun is called the "ecliptic". Compared to the ecliptic, the axis of the Earth's spin is "tilted" at a little over 23 degrees. It is this "tilt" of the Earth's spin that causes the seasons. So, WHY is the Earth's spin axis "tilted"? We may never know for sure, but at least some scientists believe that it may be related to the planetary collision that created the Moon.
This must be Uranus. "On its side" isn't a very scientific way of putting it. It means that the planet's axis is tilted at about 90 degrees (98 degrees actually) from the perpendicular to its orbital plane.
The Earth's axis of rotation is at an angle of 23.5 degrees to the plane of the "ecliptic", the orbital plane of the Earth around the Sun. In space, there is no "up" or "down"; for something to be "tilted", it has to be tilted with reference to something else. Since we're here on Earth, it makes sense to use the ecliptic as a common reference plane.
23.5 degrees. That's the angle between the axis of the Earth and a line that is perpendicular to the plane of Earth's orbit around the Sun.
The plane of the earth's orbit around the sun is not the same as the plane of the equator. The latter is tilted at roughly 23.5 degrees.
It is tilted (23.5 degrees).