In the days following Independence Day, thermometers climbed to abnormal highs in many parts of the world. With such hot temperatures as these, it might be a surprise for you to hear that on Thursday (July 6) at 4:06 p.m. Eastern Daylight Time (2006 GMT), our Earth will reach the point in its orbit where it is farthest from the sun in space.
Called aphelion, the sun at that moment will be 94,506,364 miles (152,093,250 km) from our Earth (measured from center to center), or 3,103,330 miles (4,994,325 km) farther as compared to when the Earth was closest to it (called perihelion) on Jan. 4. The difference in distance is equivalent to 3.29%, which makes a difference in radiant heat received by Earth of nearly 7 percent; a change of only one part in 30.
Indeed, it's probably no surprise that if you ask most people in which month of the year, they believe that the Earth is closest to the sun most probably would say we're closest during June, July or August. But our warm weather doesn't relate to our distance from the sun. It's because of the 23.5-degree tilt of the Earth's axis that the sun is above the horizon for different lengths of time at different seasons. The tilt determines whether the sun's rays strike us at a low angle or more directly.
At New York's latitude, the more nearly direct rays at the summer solstice of June 21 bring about three times as much heat as the more slanting rays at the winter solstice on December 21. Heat received by any region is dependent on the length of daylight and the angle of the sun above the horizon, hence the noticeable differences in temperatures that are registered over different parts of the world.
Source: www.space.com
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