<P> Excluding planetary engineering, by the time the two galaxies collide the surface of the Earth will have already become far too hot for liquid water to exist, ending all terrestrial life; that is currently estimated to occur in about 3.75 billion years due to gradually increasing luminosity of the Sun (it will have risen by 35--40% above the current luminosity). </P> <P> When two spiral galaxies collide, the hydrogen present on their disks is compressed producing strong star formation as can be seen on interacting systems like the Antennae Galaxies . In the case of the Andromeda--Milky Way collision, it is believed that there will be little gas remaining in the disks of both galaxies, so the mentioned starburst will be relatively weak, though it still may be enough to form a quasar . </P> <P> The galaxy product of the collision has been nicknamed Milkomeda or Milkdromeda . According to simulations, this object will look like a giant elliptical galaxy, but with a center showing less stellar density than current elliptical galaxies . It is, however, possible the resulting object will be a large disk galaxy, depending on the amount of remaining gas in the Milky Way and Andromeda . </P> <P> In the far future, roughly 150 billion years from now, the remaining galaxies of the Local Group will coalesce into this object, that being the next evolutionary stage of the local group of galaxies . </P>

The andromeda galaxy will eventually collide with the milky way