Today, July 4, 2014 the Earth reaches its farthest point away from the sun. This is called aphelion or in U.S. we call it Independence Day. Aphelion occurs when the Northern Hemisphere is experiencing summer. The point in orbit where a planet is nearest to the sun is called the perihelion. The word aphelion derives from the Greek words, apo meaning away or off and Helios (the Greek god of the sun). Earth’s aphelion usually occurs sometime around July 4. At aphelion our planet is around 152 million kilometers (94 million miles) away from the Sun. This is in contrast to perihelion when it is 147 million kilometers away from the Sun, and it currently occurs around January 3.

It seems odd to know that the Earth is farther away from the sun for us northern hemisphere folks when summer is coming on strong while in January when it’s usually bitterly cold we, in fact, are closer to the sun!

As it turns out the seasons are really a factor of the Earth’s 23.5 degree tilt on its axis. So in winter when we are closest to the sun the tilt of the earth on it’s axis is away from the sun for the northern hemisphere and toward the sun for the southern. So axis tilt and not so much distance are the determining factors in the home planet’s seasons. Of course if you increase or decrease the distance from the sun significantly you undoubtedly will affect the temperatures on the planet. Thankfully, nobody has figured out an easy way to accomplish that maneuver.