In about six billion years from now, our home galaxy Milky Way (MW) and the neighbouring Andromeda galaxy (M 31) will collide and merge with each other giving rise to a new combined elliptical galaxy. This is the current understanding about future of our home galaxy Milky Way. However, using data from the latest observations by the Gaia and Hubble space telescopes, researchers have found that Milky Way-Andromeda collision is far less inevitable. The two galaxies may not necessarily merge and the probability of “no Milky Way–Andromeda merger” scenario is close to 50 %.
What will happen to Earth, to Sun and to our home galaxy in future? They will not remain the way they are for ever. Earth will remain habitable for another 4 billion years if not destroyed earlier by manmade or natural disasters like nuclear war, drastic climate change, impact with an asteroid, massive volcanic eruption, etc. In about 4 billion years from now, Sun will run out of hydrogen that fuels nuclear fusion in its core for energy generation when gravitational collapse begins. Increased pressure due to core collapse will trigger nuclear fusion of heavier elements in the core. As a result, temperature of Sun will increase, and the outer layer of solar atmosphere will expand far out in the space and engulf nearby planets including Earth. This red giant stage will continue for about a billion year. Eventually, Sun will collapse to become a white dwarf.
As for our home galaxy Milky Way (MW), the current understanding is that the future evolution of the Local Group (LG) that contains more than 80 galaxies including the two large spiral galaxies Milky Way (MW) and the Andromeda galaxy (M 31) will be driven by the dynamics of the Milky Way and the Andromeda galaxy system. In four billion years from now, the neighbouring Andromeda galaxy presently situated 2.5 million light-years away will inevitably collide with our home galaxy at 250,000 mph. It is believed that process may have begun, and the two galaxies may already be on a collision course. The clash will last for 2 billion years and finally the two galaxies will merge in six billion years from now to give rise to a new combined elliptical galaxy. The solar system and the Earth will survive the merger but will have new coordinates in space.
There seems to be a consensus among experts about certainty of collision and merger of Milky Way with the neighbouring Andromeda galaxies in the Local Group. It is believed that the two will inevitably merge with each other in future to give rise to a combined galaxy. However, a new study suggests that the collision may not be inevitable.
Using data from latest observations by the Gaia and Hubble space telescopes, researchers investigated how the Local Group will evolve over the next 10 billion years. They found that the other two massive galaxies in the Local Group namely M33 and the Large Magellanic Cloud radically influence the Milky Way–Andromeda orbit. Further, the orbit of the Large Magellanic Cloud galaxy runs perpendicular to the Milky Way–Andromeda orbit which makes collision and merger of Milky Way and Andromeda less likely. The researchers found that Milky Way-Andromeda collision is far less inevitable. The two galaxies may not necessarily merge and the probability of “no Milky Way–Andromeda merger” scenario is close to 50 %.
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References:
- Schiavi R. et al 2020. Future merger of the Milky Way with the Andromeda galaxy and the fate of their supermassive black holes. Astronomy &Astrophysics Volume 642, October 2020. Published 01 October 2020. DOI: https://doi.org/10.1051/0004-6361/202038674
- Sawala, T., Delhomelle, J., Deason, A.J. et al. No certainty of a Milky Way–Andromeda collision. Nat Astron (2025). Published: 02 June 2025. DOI: https://doi.org/10.1038/s41550-025-02563-1
- ESA/Hubble Science. Hubble casts doubt on certainty of galactic collision. Posted 2 June 2025. Available at https://esahubble.org/news/heic2508/
- ESA. Hubble and Gaia revisit fate of our galaxy. Posted 2 June 2025. Available at https://www.esa.int/Science_Exploration/Space_Science/Hubble_and_Gaia_revisit_fate_of_our_galaxy
- NASA. Apocalypse When? Hubble Casts Doubt on Certainty of Galactic Collision. Posted 2 June 2025. Available at https://science.nasa.gov/missions/hubble/apocalypse-when-hubble-casts-doubt-on-certainty-of-galactic-collision/
- University of Helsinki. Press release – No certainty about the predicted Milky Way – Andromeda collision. Posted 02 June 2025. Available at https://www.helsinki.fi/en/news/space/no-certainty-about-predicted-milky-way-andromeda-collision
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 and the neighbouring Andromeda galaxy (M 31) will collide and merge with each other giving rise to a new combined elliptical galaxy. This is the current understanding about future of our home galaxy Milky Way. However, using data from the latest observations by the Gaia and Hubble space telescopes, researchers have found that Milky Way-Andromeda collision is far less inevitable. The two galaxies may not necessarily merge and the probability of “no Milky Way–Andromeda merger” scenario is close to 50 %.){kind=link}