The growing demand for energy in our world makes man look at the Sun with new eyes: as a seemingly inexhaustible source of energy that can meet all our needs. The Sun is now revealed to us as a source of energy that can be exploited by mankind in a much more efficient and comprehensive way than it is today. Indeed, directly, or indirectly, the Sun is the primary source of all energy on Earth.
Sunlight is the lifeblood of all organisms on our planet. This same solar radiation, assimilated in photosynthesis, is transformed into plants, and plants are the staple food of many animals. The decomposition of plants and other living things millions of years ago stored solar energy in the form of fossil fuels (coal, oil and natural gas). The Sun is also the cause of many other energetic phenomena on Earth, such as atmospheric winds or ocean currents. The nuclear energy generated on Earth has its origin in the heavy elements that were created either in the center of the Sun or some other star. The Earth itself, along with the other planets of the Solar System, is but a somewhat «by-product» created during the formation of the Sun.
The Sun appears to be a nondescript star in a nondescript galaxy. In astronomical terms, the Sun is classified as a star of spectral type G2 and luminosity class V: a «G2V» star. This is a quick way of saying that it is a yellow dwarf star, with a surface temperature of 5 780 K1 , composed essentially of Hydrogen (74 % by mass and 92 % by volume) and Helium (24.5 % by mass and 7 % by volume), to which are added small traces of heavy elements such as Iron, Nickel, Oxygen, Silicon, Sulfur, Magnesium, Carbon, Neon, Calcium and Chromium.
But, for the Earth and for us its inhabitants, the Sun is a unique star: our star. During the day, the Sun makes other celestial bodies pale, its blinding brightness does not allow us to look at it directly. The Sun has been an object of curiosity and study for all civilizations. Many ancient communities considered it a god and dedicated monuments and observatories to it. In Egypt, in Greece, in America, in the Far East, all over the world we can find countless examples and curiosities that illustrate the fascination and recognition of the light and heat provided by the Sun as a source of life and energy.
I invite you to read Matias’ post with the theme of the day
Finally, I encourage everyone to reflect on the concept of the day. No one else but us can re-signify our own being