 A star is a luminous sphere of plasma held together by its own gravity . 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 . 
 A star <a href='drop_aux' title='1'><mark>is</mark></a>a luminous sphere of plasma held together by its own gravity . The nearest star to Earth <a href='drop_aux' title='2'><mark>is</mark></a>the Sun . Many other stars <a href='drop_aux' title='3'><mark>are</mark></a>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 <a href='uninflect' title='4'><mark>were</mark></a> grouped into constellations and asterisms , the brightest of which gained proper names . Astronomers <a href='been_done' title='5'><mark>have</mark></a> assembled star catalogues <a href='null_relcl' title='6'><mark>that</mark></a>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 , <a href='drop_aux' title='7'><mark>are</mark></a>invisible to the naked eye from Earth . Indeed , most <a href='drop_aux' title='8'><mark>are</mark></a>invisible from Earth even through the most powerful telescopes . 
A star a luminous sphere of plasma held together by its own gravity . The nearest star to Earth the Sun . Many other stars visible to the naked eye from Earth during the nite , appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth . Historically , da most prominent stars was grouped into constellations and asterisms , the brightest of which gained proper names . Astronomers done assembled star catalogues 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 , invisible to the naked eye from Earth . Indeed , most invisible from Earth even through the most powerful telescopes .