Summer Solstice 2024 | 21 Jun 2024

Source: IE

Why in News?

Recently, 21^st June has been marked as the day of the summer solstice in the northern hemisphere of the world.

• The summer solstice is celebrated as the beginning of summer, or midsummer when one of Earth’s poles is at its maximum tilt towards the sun.

What is the Summer Solstice?

• Origin:
  • Origin of Summer Solstice can be traced to around 200 BC when ancient Greek scholar Eratosthenes, conducted a experiment to measure the Earth’s circumference.
  • He observed that on the summer solstice, sunlight shone directly down a well in Aswan, Egypt, indicating the sun was directly overhead.
  • By calculating the difference in shadow lengths between Awan and Alexandria cities and the distance between them, Eratosthenes was able to provide an early and accurate estimate of the Earth’s circumference.
• About:
  • The summer solstice marks the longest day of the year, when the sun reaches its highest point in the sky.
  • During the solstice, the Earth’s axis (around which the planet spins, completing one turn each day) is tilted in a way that the North Pole is tipped towards the sun and the South Pole is away from it.
  • Typically, this imaginary axis passes right through the middle of the Earth from top to bottom and is always tilted at 23.5 degrees with respect to the sun.
  • At the Arctic Circle(66°33′ north latitude), the sun never sets during the solstice.
  • The amount of light received by a specific area in the Northern Hemisphere during the summer solstice depends on the latitudinal location of the place.
• Effect:
  • During this, countries in the Northern Hemisphere are nearest to the Sun and the Sun shines overhead on the Tropic of Cancer (23.5° North).
  • The Earth rotates on its axis, causing the Northern Hemisphere to receive more direct sunlight between March and September.
    • The amount of incoming energy the Earth receives from the sun on this day is 30% higher at the North Pole than at the Equator.

• Cultural Significance:
  • In many cultures, summer Solstice is a significant time of the year which marks festivals and rituals across the globe.