Changes

The sun has a diameter of about 1.4 million kilometer; some 1.3 million Earths could fit inside its volume. It is an average-sized, middle-aged star. Its surface temperature is 6000 K, while the temperature of its core is around 13.6 million K. The inner layer of the sun, called the core, is where most fusion takes place. Beyond that is the radiation zone and then the convection zone. Outside that is the photosphere, the visible layer of the sun. It takes anywhere between 17,000 and 50 million years for photons produced in the core to be emitted at the surface, having been absorbed and re-emitted countless times. The atmosphere, including the corona, surrounds the photosphere. The sun is located about halfway between the center of the galaxy and its edge; it takes around 230-250 million years to orbit the galactic center. It is estimated to have made almost twenty of these trips.

The sun has a diameter of about 1.4 million kilometer; some 1.3 million Earths could fit inside its volume. It is an average-sized, middle-aged star. Its surface temperature is 6000 K, while the temperature of its core is around 13.6 million K. The inner layer of the sun, called the core, is where most fusion takes place. Beyond that is the radiation zone and then the convection zone. Outside that is the photosphere, the visible layer of the sun. It takes anywhere between 17,000 and 50 million years for photons produced in the core to be emitted at the surface, having been absorbed and re-emitted countless times. The atmosphere, including the corona, surrounds the photosphere. The sun is located about halfway between the center of the galaxy and its edge; it takes around 230-250 million years to orbit the galactic center. It is estimated to have made almost twenty of these trips.

The sun produces a vast amount of energy; the Earth receives only a tiny fraction of this energy, yet it powers practically all life (and industry) on Earth, either directly or indirectly. It is also responsible for Earth's climate and weather. Plants and other organisms capture the energy of the sun in a process called [[photosynthesis]]. Animals and other heterotrophs obtain food and energy from consuming plants or from consuming animals who have consumed the plants. Only a few microscopic organisms obtain energy directly from chemical reactions; this represents a very ancient metabolic pathway and likely existed prior to the evolution of photosynthesis.

The sun produces a vast amount of energy; the Earth receives only a tiny fraction of this energy, yet it powers practically all life (and industry) on Earth, either directly or indirectly. It is also responsible for Earth's climate and weather. Plants and other organisms capture the energy of the sun in a process called [[photosynthesis]]. Animals and other heterotrophs obtain food and energy from consuming plants or from consuming animals who have consumed the plants. Only a few microscopic organisms obtain energy directly from chemical reactions; this represents a very ancient metabolic pathway and likely existed prior to the evolution of photosynthesis.