solar system
First of all, let me talk about the reason why the distance between the earth and the sun has multiple sets of values: the distance between the earth and the sun refers to the distance between the sun center and the earth center. Because the earth's orbit around the sun is elliptical, the distance between them is constantly changing. When the earth revolves to perihelion, that is to say, the distance from the earth to the sun is the farthest, about 15265438+ million kilometers; When the earth revolves to perihelion, that is to say, the distance between the earth and the sun is the closest, about 14765438+ million kilometers; During the whole revolution, the average distance between the earth and the sun is about 1.496 million kilometers.
solar system
Next, I will give you a brief introduction to the method of measuring the distance between the earth and the sun. There are two main methods of measurement:
Using transit of venus phenomenon to measure.
When the sun, Venus and the earth are in a straight line, the earth sends out a radar wave, which hits Venus and then reflects back from Venus, thus measuring the distance between the earth and the sun. With this method, the average distance from the earth to the sun can be measured, which is about 654.38+0.496 million kilometers. The idea of using transit of venus phenomenon to measure the distance between the earth and the sun was first put forward by Harley in 17 16.
Using asteroids to measure
Because the transit of venus phenomenon is rare, scientists also use asteroids to measure the distance between the earth and the sun.
I hope today's sharing can provide you with some references to help you understand this problem.
See you next time!
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