New Delhi, Jan 5 (): The Earth will be at a special place in its orbit, being very close to its perihelion – its closest point to the sun for the year. This will give good opportunity to astro-enthusiasts to carry out several experiments.
“At 5.53 am on Thursday, the Earth will be at its nearest point from the Sun. The distance at that time is 147 million km,” Planetary Society of India General Secretary N Sri Raghunandan Kumar said on Wednesday.
Every January, the Earth gets to the closest distance from the Sun for the year and in July, it is at aphelion, the farthest to the Sun for the year, he said. All planets, comets and asteroids in our solar system have elliptical orbits. Thus, they all have the closest and the farthest point from the Sun– a perihelion and an aphelion, he added.
The distance from the centre of the Earth to the centre of the sun will be 147,097,206.9 km at the moment of Perihelion. The word ‘Perihelion’ means “peri” – near and “helios” – sun, according Greek language.
Earth has a slightly elliptical orbit around the sun with an eccentricity of 1.7 percent or about 5 million kilometres. In January, Earth is closest to the Sun. and in July, it is farthest from the Sun.
Though not responsible for the seasons, Earth’s closest and farthest points to the sun do affect the lengths of the seasons. When the Earth comes closest to the sun for the year, as now, our world is moving fastest in orbit around the sun.
Earth is rushing along now at 30.3 kilometers per second (almost 19 miles per second) – moving about a kilometre per second faster than when Earth is farthest from the sun in early July. Thus the Northern Hemisphere winter (Southern Hemisphere summer) is the shortest season as Earth rushes from the winter solstice in December to March.