Why is the Earth tilted at 23.5 degrees?

Answer 1

There is no consensus as to what caused the Earth to have an axial tilt of 23,5 degrees to the ecliptic (its orbital plane around the Sun). Most planets axes have some tilt, Uranus' axis tilts as much as 89 degrees!

Answer 2

After millions of years passed enough matter collided to gain mass and its own gravity and become small versions of planets called planetessimals and protoplanets. These pre planets collide to create even larger planets. This set the stage for how the Earth approached its final form. It looks like it probably collided with a another proto planet and in the process it was tilted.

All the same the Earth's tilt is very important. It is perfectly positioned so that it gives us the seasons and on top of that the seasons are near perfectly calibrated for life. When compared with other planets Earth's tilt allows for season that are not two extreme in temperature but are pretty well balanced. At the same if it had stay in the "perfect" position one side of the Earth would be too hot at time and then too cold.

Answer 3

Don't know technically exactly how it was done, but the north and south tropics, the parallels where the sun reaches zenith at the time of the solstices, are 23.4 degrees north and south of the equator. The zenith is the point in the sky that is exactly over-head, wherever you happen to be. So the earth must tilt that much in order for the sun to reach those points.

Answer 4

Most planets have an axis tilted with respect to their orbit around the sun. The Earth's axis is tilted off perpendicular by 23.5 degrees. If the Earth was formed as it is believed, from matter circling the star we call the Sun, then its axis should be more perpendicular to its orbit. Many things could have cause the tilt of the axis, from long term imbalances in the geological makeup of the earth, to gravitational effects of the moon, or even form the collision between the earth and the object that formed the moon from the earth's crust. Computer simulations may tell us one day what most likely happened or what seires of events all contributed to the current tilt, along with data from moon rocks and its geology.

The planet Uranus has a rotational angle of 98 degrees.

http://www.newton.dep.anl.gov/askasci/ast99/ast99596.htm

dig in and get what you can from it.

http://adsabs.harvard.edu/full/1901AJ.....22...56P

Answer 5

At the moment the Earths tilt - or Axial tilt - is about 23.4o but it has not always been that value. Over a million years it has varied between 22o and 24o.

So why the tilt? It's not known for sure but a good suspect is the collision that occurred about 4.5 billion years ago, when Theia, a planet about the size of Mars, smashed into Earth. The impact, not only ejected material that created the Moon, but also could have destabilised the axis of the Earth.

Without the Moon, the Earth would have gone into axial freefall, tilting as much as 90o but because of the Moon, we have seasons, a stable tilt and a life.

The Moon is slowly receding away from the Earth and in about 2 billion years, Earths tilt will start to resonate.

Not to worry we will be long dead or at least pushing onwards to new sunnier climes.
We don't know why the Earth spins at an axial tilt of about 23.5 degrees. Some possibilities are...

1. That's the way the Earth formed naturally.

2. The collision with another planet (perhaps as large as Mars!) knocked the Earth a little sideways. We believe that this collision blasted enough mass off of the combined planet to create the Moon.

Answer 6

Yes, that is close enough. This represents the angle between the Earth's axis and the perpendicular to the Earth's orbit around the Sun. (That is to say, a planet whose axis is perpendicular to its orbit would have a tilt of 0 degrees.)

Answer 7

All you have to do is keep track of the sun's positions in the sky during the year.

If you pay close attention and keep some records, you notice that the days

on which the sun's highest positions at mid-day are farthest north and farthest

south are always near June 21 and December 21.

(The way I worded that statement, it's true in both the northern and the southern

hemispheres.)

The 'tilt' of the Earth's axis is simply 1/2 of the difference between those extreme

positions of the sun during a year.

The technology required to make these measurements has existed for more than

3,000 years.

Answer 8

Tilted relative to what? In space, there is no "up" or "down", so in order to measure the tilt of something, you have to provide a plane of reference.

Fortunately, there is a handy and convenient plane of reference to use, which is the ecliptic. "Ecliptic" is the special name that we use to mean "the plane of the Earth's orbit around the Sun". As compared to the ecliptic, the imaginary axis of the Earth's rotation is about 23 2/3 degrees. Since the Earth is spinning, it acts like an enormous gyroscope, which maintains its orientation in space, so it keeps this "tilt" constant as the Earth orbits the Sun, or in other words, "as the years go by".

So, no, the Earth is not tilted at 25 degrees; about 1.3 degrees less than that.

Answer 9

There is no reason, it is just an observed fact.

Answer 10

Yes, the angle between Earth's equatorial plane and its orbital plane is 23.5 degrees and hence "tilted".