The Earth’s orbit around the sun traces a circle against the stars in the background. This is known as the ecliptic due to its role in determining the timing and location of eclipses.
Credit: Wikimedia user Tfr000
The ecliptic is the apparent path of the sun across the sky. The path is “apparent” because it is the Earth that is actually making this path (we just see it portayed on the sun because we are stationary observers on the Earth). The apparent path of the sun is generally not discernible to the everyday observer due to the Earth’s rotation and our resulting sunrise/sunset cycles. However, you can trace the ecliptic more easily at night by seeing which constellations are visible at different times of the year.
By definition, the plane of the ecliptic is the same as the Earth’s orbital plane around the sun. Additionally, all of the planets in the solar system lie very close to the ecliptic plane. Next time you are out stargazing and you see one of the planets, see if you can find the others in the ecliptic!
Saturn, Mars, Venus, and Mercury lying in the ecliptic plane. Looking west (sunset) at Surakarta, Java, Indonesia.
Credit: Jia How
Written by Charlie Phillips – charlie.weathertogether.net. Last updated 12/1/2017