What is a star?
|Automatic translation||Updated June 01, 2013|
A star is a object similar to our sun, which shines through nuclear reactions that occur in the center.
The number of stars in the universe is estimated between 1022 and 1023.
Image: Birth of a star image made from data of X-ray telescope Chandra (blue) and data from the Spitzer infrared telescope (red and orange). NB: The astronomers classify stars in dwarf or giant.
Yellow dwarfs are stars of medium size. A yellow dwarf is a star belonging to the main sequence of spectral type G and weighing between 0.7 and 1 times the solar mass.
Image: The Sun is a yellow dwarf star. NB: The astronomers classify stars in dwarf or giant.