Axis Tilt: Observation In The Northern Hemisphere

Axis Tilt
The Earth is tilted on it’s axis at about a 23.45 degree angle perpendicular to the Plane of the Eclipt. Because of Earth's tilt, different regions of earth receive different amounts of direct and indirect sunlight. We call these various periods of time the seasons. When the Northern Hemisphere is tilted towards the sun it is experiencing summer, simultaneously, the Southern Hemisphere is experiencing winter, because it is tilted away from the Sun. During the Winter, the days are shorter because the sun rays hit the Earth at such an extreme angle. During the summer, days are longer because the sun is hitting the earth at a more direct angle. Earth's tilt is one of the main causes of the seasons, because it exposes different regions
to the sun depending on where we are in our orbit around the sun.

Revolution around the sun
Earth's revolution around the sun is a vital aspect of the seasons. If earth was not orbiting around the sun, we would constantly be experiencing one season. The earth’s tilt and rotation, on their own, are not enough to cause the seasons. As Earth revolves around the sun, different areas of Earth receive more direct sunlight than others. Without revolution around the sun, the hemispheres would be forever trapped in one season. However, because the earth is able to revolve around the sun, we experience the seasons. When the northern hemisphere is experiencing summer we are able to know that in six months, we will have been halfway around the sun and will then be experiencing winter.

Angle of Sunlight
The angle in which sunlight touches the earth, causes the seasons.
In late march and late september, we experience the equinoxes. This is when the sun rises in the east on the equator and sets in the west directly on the equator. This is when the sunlight is most direct on the equator. After the March equinox the sun will begin to appear like it is rising and setting more to the north. In late June, the summer solstice, the sun appear highest in the sky and began to move back south toward the equator. After the september equinox the sun will appear to move south, until late December, the winter solstice. The angle of sunlight is important because based upon the angle there will be different amounts of energy per unit of light. More energy means more heat so when the Sun appears farther from the earth, more heat is being produced because light is hitting earth's surface directly, for longer. This cycle causes seasons, because it affects how much energy earth is receiving from the sun's
light.

Direct/Indirect Sunlight
Direct and indirect sunlight cause the seasons.
Direct and indirect sunlight are a result of Earth's tilt on it’s axis. When sunlight hits an object directly it is heated at a greater rate because it receiving more energy per unit affected. If the same object receives indirect sunlight it will heat at a lower rate because there is less energy per unit affected. In the summer, the sun is above the horizon longer than in the winter, because it is receiving more direct sunlight. The hemisphere experiencing summer will be warmer because it receives more direct sunlight for longer. Whereas the hemisphere experiencing winter will be cooler because it receiving less indirect sunlight. Direct and indirect sunlight are an important factor in why we experience the
seasons.

What would happen if earth was not tilted?

If the earth was not titled, we would not experience seasons. As the earth would revolve around the sun, the equator would receive all direct sunlight and the poles would get no sunlight causing them to be much colder. Everyday in the year would be the same length, but every location on earth would receive sunlight for different amount of times.The equator would be very hot all year long. This is because the sunlight would be worth more per unit, because it would be hitting the equator directly. The seasons would exist because no matter where the earth is in relation to the sun, it would constantly be the same conditions.