Search results
Results From The WOW.Com Content Network
This diagram shows how the tilt of Earth's axis aligns with incoming sunlight around the winter solstice of the Northern Hemisphere. Regardless of the time of day (i.e. the Earth's rotation on its axis), the North Pole will be dark and the South Pole will be illuminated; see also arctic winter.
This is a diagram of the seasons. Regardless of the time of day (i.e. Earth 's rotation on its axis), the North Pole will be dark, and the South Pole will be illuminated; see also arctic winter . Figure 3 shows the angle of sunlight striking Earth in the Northern and Southern Hemispheres when Earth's northern axis is tilted away from the Sun ...
The seasons occur because the Earth's axis of rotation is not perpendicular to its orbital plane (the plane of the ecliptic) but currently makes an angle of about 23.44° (called the obliquity of the ecliptic), and because the axis keeps its orientation with respect to an inertial frame of reference. As a consequence, for half the year the ...
Given the different Sun incidence in different positions in the orbit, it is necessary to define a standard point of the orbit of the planet, to define the planet position in the orbit at each moment of the year w.r.t such point; this point is called with several names: vernal equinox, spring equinox, March equinox, all equivalent, and named considering northern hemisphere seasons.
Diagram of Earth's seasons as seen from the north. Far left: summer solstice for the Northern Hemisphere. Front right: summer solstice for the Southern Hemisphere. Although the summer solstice is the longest day of the year for that hemisphere, the dates of earliest sunrise and latest sunset vary by a few days. [8]
An idealised view of three large circulation cells showing surface winds Vertical velocity at 500 hPa, July average. Ascent (negative values; blue to violet) is concentrated close to the solar equator; descent (positive values; red to yellow) is more diffuse but also occurs mainly in the Hadley cell.
Systematically observing the sunrise, people discovered that it occurs between two extreme locations at the horizon and eventually noted the midpoint between the two. Later it was realized that this happens on a day when the duration of the day and the night are practically equal and the word "equinox" comes from Latin aequus, meaning "equal", and nox, meaning "night".
Illumination of Earth by the Sun on the day of the June solstice. The June solstice is the solstice on Earth that occurs annually between 20 and 22 June according to the Gregorian calendar.