Earth revolves around Sun in an elliptical orbit. So at one point of time during its journey around the sun, it will be at the closest point it can get (perihelion) and at one point of time during the year it would be at the farthest point (aphelion). On 2nd January 2021 at 7.27 pm Planet Earth will reach the closest point to Sun in its annual elliptical orbit around Sun at 0.9832571 AU i.e. at 14,70,93,168 km from Sun. Astronomically this phenomenon is known as “Perihelion”. Whereas on 6th July 2021 at 3:46 a.m. IST Earth will be at Aphelion at 1.0167292 AU (15,21,00,523 km) from Sun i.e. which is the farthest point from Sun.I
Inother words, due to Perihelion on 2nd Jan 2021 Earth, tomorrow will be 50,07,355 km closer to Sun compared to 6th July 2021. Though people will not
able to notice or observe this celestial event. This event is of greatest
importance with educational potential for students and the public to understand
temperatures or Seasons on Earth are not dependant on the distance of Earth to the
Sun but axial tilt during its journey around the Sun.
Distance not Reason for Seasons: Commonly it is believed that the distance of Earth to the Sun decides the season or temperature on Earth. However, it is not true. Axial tilt (approx. 23.5 Degree) of Earth on its axis while revolving around Sun regulates seasons on planet Earth with one of the Hemisphere facing away or towards Sun.
Evidence/Example: At the beginning of the year every January Month it is winter in most of the countries in the Northern Hemisphere. Whereas Earth is at closest it can get to Sun at beginning of the year 2021. Whereas it’s summer in Southern Hemisphere countries. Also in July when Earth is at the farthest point from Sun it’s mostly hot in India compared to what it is in January. This clearly shows Distance of Earth to Sun doesn’t decide the Season but its tilt during its yearly journey around Sun.
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