In 4 billion years' time, the Milky Way galaxy will collide with the Andromeda galaxy -- scattering stars across the universe.
NASA made the announcement at a conference Thursday following an extensive study of data collected by the Hubble telescope.
Neighbouring galaxy Andromeda, which is 2.5 million light years away, is said to be moving towards the Milky Way at 400,000 kilometres per hour.
It was initially thought that the galaxies would bypass one another -- but recent evidence has dispelled that.
Scientists can now confirm that they will be involved in a head-on collision.
While many stars and planets - including the Earth - are likely to survive the impact of the 1.9 million kilometre per hour crash, they will likely be thrust into a different part of the cosmos.