Mere million, mere aphelion

Today, our planet Earth is at aphelion, the point in its orbit when it is farthest from Hêlios, the Sun.

Here are the distances at perihelion (January 2) and aphelion (July 5), and the difference between them, in astronomical units (the average distance), kilometers, and miles.

  AU      km         mi
0.9833  147,099,586  91,403,672
1.0167  152,096,155  94,508,404
0.0334    4,996,569   3,104,732

Aphelion occurred at 6h Universal Time, which by clocks on shifted summer time was 5 AM in Britain and midnight in America. Di you feel colder than in January because you were 3 million miles farther from the Sun? I certainly didn’t. The difference is almost trivial compared with the total distance, because Earth’s orbit is close to being a circle.

The cause of our seasons is not distance from the Sun; it is the tilt of our hemisphere of the planet toward or away from the Sun.

Tomorrow morning, you will be thousands of miles nearer to the Sun. And you may feel a shade warmer. But that will be because the hottest weather tend to come with a delay after midsummer.

 

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