I know that in the winter equinox the axis is as far away from the sun as it’s going to get. Each day after that it moves closer towards the sun. What is it called ? Sunward, that a way?
In: Planetary Science
>I know that in the winter equinox the axis is as far away from the sun as it’s going to get
Incorrect on two counts. There is no winter equinox, there is a winter solstice. The equinoxes are in spring and autumn.
And the winter solstice is not when the Earth is farthest from the sun, it’s when the Earth’s tilt means your hemisphere receives the least amount of sunlight. It also means that the winter solstice in the northern hemisphere is the same as the summer solstice in the southern hemisphere, and vice-versa.
The point at which the Earth is furthest from the sun is called the apihelion, and it is usually around July 5.
In the winter *solstice*, the *north pole* is *pointed* as far away from the sun as it’s going to get. The process of the rotational axis “flipping” from winter to summer is called spring.
O is the sun, / is the Earth’s axis
Northern hemisphere summer
/ O
The north pole is tilted toward the sun, and the south pole is tilted away. The exact day is the solstice, and the Southern hemisphere is in winter.
6 months later, the Northern hemisphere winter
O /
The Earth is still tilted the same way, but it’s now on the other side of the sun. Now the North is in winter, and the South is in summer.
In between are the equinoxes
Ø
The Earth is still tilted, but from this side view diagram I’m drawing, the Earth is in front of or behind the sun. Neither pole is tilted towards or away from the sun, but the axis is still tilted.
The earth’s axis doesn’t move (at least not on timescales relevant to this discussion). It always points in the same direction. If you put a Sun and an Earth on a table in a room, the north pole could be pointed toward one corner of the ceiling. If you move the Earth around the Sun on the table to simulate a year, no matter what, the axis will still be pointed toward that corner.
If you do that then you can see that sometimes the Sun will be “in front” of that corner (the axis has to point “over” it) and sometimes on the other side of the earth from the corner.
When the Sun is “in front” of the corner, the north pole is in summer. Six months later, the north pole is in winter.
You could use the term “sunward” or “inward” to describe a direction that’s moving toward the Sun, but it’s not the Earth’s axis that’s doing the moving. The Earth is orbiting the Sun and bringing it in and out of prominence for each hemisphere.
Latest Answers