Star
Wiki, Facts

 Star facts

• The nearest star to Earth is the Sun
• Many other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth
• Historically, the most prominent stars were grouped into constellations and asterisms, the brightest of which gained proper names
• Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations
• However, most of the stars in the Universe, including all stars outside our galaxy, the Milky Way, are invisible to the naked eye from Earth
• Indeed, most are invisible from Earth even through the most powerful telescopes
• For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space
• Almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the star's lifetime, and for some stars by supernova nucleosynthesis when it explodes
• Near the end of its life, a star can also contain degenerate matter
• Astronomers can determine the mass, age, metallicity (chemical composition), and many other properties of a star by observing its motion through space, its luminosity, and spectrum respectively