Why Do Humans Look to the Stars for Answers?
The energy activity within stars causes them to develop irregular shapes. Stars can be broadly categorized as planets, stars, comets, and white dwarfs. The brightness of stars is often expressed in magnitude. The brighter the star, the lower its magnitude. The brightest planet is Venus, the fastest star orbits at speeds exceeding 240 kilometers per second, and H1504+65 is the hottest white dwarf.
Astronomers estimate that the number of stars in the observable universe is approximately 200 trillion trillion (or 2×10^23). The vast majority of stars in the sky revolve counterclockwise around the North Star, maintaining their relative positions, hence the name "stars." However, five bright stars break this pattern and travel between the stars, hence the name "planets."
What are stars？
- Planets themselves do not emit light; we see it as reflected sunlight.
- Stars are large celestial bodies, like the sun, that undergo internal reactions and radiate energy into space as light.
- The light we see from comets like Halley's Comet is the result of their tails, which are formed when the material melts as they pass through the solar system. This is why comets often have long tails. Most of the stars visible at night are fixed stars, with a few being planets in our solar system, such as Venus, Mercury, and Mars. The principle of light generation in these stars is similar to that of our sun: most of the energy is released by the fusion of hydrogen into helium nuclei, while some is released by helium fusion. They appear as small, gentle stars only because they are so far away; in reality, they are much larger than the sun. Planets appear bright because they reflect sunlight. They simply absorb the light from their proximity, making them appear brighter than fixed stars.
Star Classification
Stars are classified by type: stars, planets, satellites, dwarf planets (this classification only applies to the solar system), and small bodies (asteroids, comets, etc.)
Stars are classified by phase: nova, main sequence, red giant, and supernova (divided into the following categories): 1. White dwarf, 2. Neutron star, 3. Black hole
Stars are classified by size: (brown-red) dwarf, (blue, blue-white, yellow, red) giant, (blue, red) supergiant
Stars are classified by spectrum: O, B, A, F, G, K, M, and additional R, N, S, etc.
Stars are classified by composition: single, binary, multiple, and cluster stars
Other star classifications: non-variable and variable stars
Variable stars are classified into Cepheid variables and eclipsing variables
Planets are classified by composition and size: Jovian and Terrestrial
The Impact of the Starry Sky on Human Experience
We are captivated and fascinated by the myriad wonders of the starry sky. Every time a shooting star streaks across the night sky, a fleeting flash of lightning, or the sun and moon rising and setting each day, they all silently captivate our gaze. This sky, which has accompanied us from ancient times to the present, constantly inspires our curiosity and desire for exploration. Gazing at the starry sky brings a sense of happiness, allowing us to indulge in thoughts of family, longings for life, and fantasies about the future. It possesses the power to heal the soul. As we explore the infinite mysteries of the sky, the scientific and mythological traditions left behind from ancient times to the present serve as precious witnesses to our journey as civilization.
