The Sun’s journey from one end of the ecliptic to the other, or from the right edge of the map to the left edge of the map, is exactly one year, then the cycle repeats. There are four very important points through which the Sun passes in its annual journey across the ecliptic.
As Earth orbits the sun, the sun appears to drift across the background stars. The ecliptic marks out the path of this motion on the sky.
At the time of crossing, the Sun may be anywhere along the ecliptic; usually it is not on the Earth-Moon line, and therefore an eclipse usually does not take place. Occasionally, however, it is on that line or close to it.
The sun drifts leftward by about one degree per day, moving first into the northern half of the sky and then, after the September equinox, into the southern half. The Sun from Different Latitudes
* The Sun moves eastward relative to the stars by about 1° per day.
Each day, as the sun takes four minutes longer than the constellations to spin around us, it creeps approximately one degree eastward along the ecliptic.
As Earth orbits the sun, the sun appears to drift across the background stars. The path of the sun is the ecliptic. Image via Wikimedia Commons. The ecliptic is an imaginary line on the sky that marks the path of the sun.
The ecliptic is the path the sun, moon, and planets take across the sky as seen from Earth. It defines the plane of the Earth's orbit around the sun. The name "ecliptic" comes from the fact that eclipses take place along this line.
The line that the moon has traced across the sky over these nights is the ecliptic. At the moment, you can only use the positions of Mars and the moon in the sky to find the ecliptic, but you can observe it on most nights if you can spot a planet or the moon.
The ecliptic is the invisible path that the Sun traces as it moves around the sky. Think of it like this: if the Sun were to drop breadcrumbs behind it like a cosmic Hansel and Gretel, this is the trail it would leave behind. The Sun can always be found on the ecliptic – it never deviates from it.
The Sun spins or rotates on its axis in the same direction as Earth (counterclockwise, when looking down from the north pole). Because it is a gas, it does not rotate like a solid. Different sections rotate at different speeds! The Sun actually spins faster at its equator than at its poles.
This apparent motion across the sky is due to the rotation of Earth. As Earth turns eastward on its axis, we move along with it, creating the illusion that the Sun moves through the sky over a day.
The first major contributor to the Sun's apparent motion is the fact that Earth orbits the Sun while tilted on its axis. The Earth's axial tilt of approximately 23.5° ensures that observers at different locations will see the Sun reach higher-or-lower positions above the horizon throughout the year.
The moon and the ecliptic Its orbit around Earth is tilted by about 5.15 degrees relative to the ecliptic. This means the moon spends most of its time above or below the ecliptic. It crosses it twice each orbit: once going upward and once downward from our point of view.
what is the ecliptic? a plane, a great circle on the celestial sphere representing the sun's apparent path during the year, so called because lunar and solar eclipses can occur only when the moon crosses it.
Yes, the Sun does move in space. The Sun and the entire Solar System revolve around the center of our own Galaxy - the Milky Way.
The ecliptic got its name because the ancients saw that solar eclipses happen when the moon crosses the ecliptic during the new moon phase.
As viewed from space, the ecliptic is the Earth-sun plane. As viewed from Earth, the ecliptic is a great circle around our sky, formed by the intersection of Earth’s orbital plane with the imaginary celestial sphere surrounding us. The sun travels around our sky on the great circle of the ecliptic. The moon and planets do, too, more or less.
The moon and planets trace out a line across our sky because they all orbit the sun, more or less, in a single plane. And – as seen from Earth – we look edgewise into that flat plane of the solar system.
And so do the major planets in our solar system. This imaginary track across our sky – the sun’s path during the day – is called the ecliptic. Technically speaking, Earth’s orbit defines the ecliptic.
It crosses it twice each orbit; once going upward and once downward from our point of view. We usually see the moon close to, but not exactly alongside the other solar system objects. On the other hand, the moon sometimes passes right in front of other solar system objects, in an event called an occultation.
If we could watch the solar system from far above the Earth’s north pole, we’d see the planets, moons, asteroids, and some of the comets (but not all of them) rushing around the sun counterclockwise in this plane, like marbles rolling around a dish. Actually, the major planets are more within the dish than on it.
Planets follow the ecliptic. So the major planets – and many of the minor planets, aka asteroids – orbit the sun in more or less the same plane. We can speak of this plane as defined by Earth’s orbit around the sun: the ecliptic.
The need for this precise alignment is why eclipses happen only a couple of times a year at most. The moon's orbit is tipped five degrees relative to Earth's. Eclipses only occur when the moon crosses the ecliptic during a full or new moon.
Credit: Wikipedia. The ecliptic is an imaginary line on the sky that marks the annual path of the sun. It is the projection of Earth’s orbit onto the celestial sphere. And it is an essential part of any stargazer’s vocabulary.
The planets Mercury, Venus, Mars, and Saturn lined up along the ecliptic (red line) shortly after sunset. Image via Jia Hao/Wikipedia. Bottom line: The ecliptic traces out the apparent annual motion of the sun across the sky. The signs of the Zodiac come from the constellations that lie along this line.
The ecliptic – the line across our sky defined by the sun’s path – gets its name from the fact that eclipses can only occur along it. A lunar eclipse happens when the moon passes through Earth’s shadow, when it is directly opposite the sun on the sky.
To put that another way, the planets allow you to actually trace out the ecliptic on any clear night yourself. Right now (April 1, 2012), the moon, Jupiter, Venus, and Mars are stretched out from west to east across the sky shortly after sun set. Go out tonight and try to find them.
Though Western astrologers have only ever recognized 12 signs, there are actually 13 constellations that lie along the path of the Zodiac. The 13th, which didn’t make the astrologer’s cut, is the constellation Ophiuchus. It the Serpent-Bearer constellation, partially located along the ecliptic between the summer constellations ...
In summary: The sun appears to move along with the celestial sphere on any given day, but follows different circles at different times of the year: most northerly at the June solstice and most southerly at the December solstice. At the equinoxes, the sun's path follows the celestial equator.
In late March and late September (at the "equinoxes"), the sun's path follows the celestial equator. It then rises directly east and sets directly west. The exact dates of the equinoxes vary from year to year, but are always near March 20 and September 22. After the March equinox, the sun's path gradually drifts northward.
The ecliptic is a great circle on the celestial sphere, tipped 23.5° with respect to the celestial equator. Its orientation with respect to our horizon changes as the sphere spins around us each day. It has the orientation shown here at noon in December and at midnight in June.
For one thing, the sun takes a full 24 hours to make a complete circle around the celestial sphere, instead of just 23 hours, 56 minutes. For obvious reasons, we define our day based on the motion of the sun, not the stars.
These geographical variations in the sun's angle above the horizon also account for the major geographical variations in earth's climates. The arctic and antarctic regions are almost always cold—even in the summer when they get 24 hours of sunlight a day—because the sun's angle above the horizon is never very high.
At the North Pole, the sun is above the horizon for six straight months (March through September), spinning around in horizontal circles, reaching a maximum height of 23.5° above the horizon at the June solstice. As you travel southward in the northern hemisphere, the noon sun gets higher and higher.
The added hours of daylight are one reason why summer is warmer than winter. But there's another reason that's even more important: the angle of the mid-day sun. Notice from the illustrations above that the noon sun is much higher in June than in December. This means that the sun's rays strike the ground more directly in June. In December, on the other hand, the same amount of energy is diluted over a larger area of ground: