<P> The Milky Way contains between 200 and 400 billion stars and at least 100 billion planets . The exact figure depends on the number of very - low - mass stars , which are hard to detect , especially at distances of more than 300 ly ( 90 pc ) from the Sun . As a comparison , the neighboring Andromeda Galaxy contains an estimated one trillion ( 10 ) stars . Filling the space between the stars is a disk of gas and dust called the interstellar medium . This disk has at least a comparable extent in radius to the stars , whereas the thickness of the gas layer ranges from hundreds of light years for the colder gas to thousands of light years for warmer gas . </P>
what all is in the milky way galaxy
between 200 and 400 billion stars and at least 100 billion planets