The planets of our solar system move around the sun, the orbits of some planets you could say that form a circle perfectly ,while others are not. Some have oval shapes such as a circle when it is stretched ,what happens with this is that if the orbit which the scientists also called ellipse is a circle, the Sun is at the center but if it is oval in the Sun is at a point called focus that is not the center of the orbit.
Because the Sun is not at the center of this orbit as the planets are revolving around these approaches and away from the sun when it is near Perihelion is called and when you are away is called Aphelion.
These words have Greek origin; helios meaning sun ,peri means near and apo means away
When Earth is at perihelion is approximately 147 million km (91 million miles from the sun and when at aphelion is 152 million kilometers (almost 95 million miles) from the sun. During the aphelion earth is5 million km (more than 3 million miles) most distant from the Sun than it is at perihelion.
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