The Milky Way galaxy is often believed to be on a collision path with the neighboring Andromeda galaxy. This merger, anticipated roughly 5 billion years in the future, is expected to create a new elliptical galaxy. However, recent studies indicate that the likelihood of such a catastrophic event may be less than previously assumed.
These images depict three encounter scenarios between the Milky Way galaxy and the neighboring Andromeda galaxy. Top left: Messier 81 and Messier82. TopRight: NGC6786. BOTTOM: NGC 520. Image credits: NASA/ESA/STSCI/DSS/Till Sawala, Helsinki University/Joseph Depasquale, STSCI.
The Milky Way navigates through space, its trajectory affected by the gravitational forces from nearby galaxies, including Andromeda, Triangulum, and the Large Magellanic Cloud.
Consequently, prior studies have proposed for over a decade that the Milky Way is likely to collide with Andromeda, forming a new elliptical galaxy referred to as Milkomeda in about 5 billion years.
Dr. Thiru Sawara, an astronomer at the University of Helsinki, stated:
In their latest research, Dr. Sawara and colleagues utilized updated data from the ESA Gaia satellite and the NASA/ESA Hubble Space Telescope to model the Milky Way’s movement through space over the next 10 billion years, while also refining estimates of the masses of local galaxies.
They discovered that there is about a 50% chance that no collision will occur between the Milky Way and Andromeda during this time frame.
The authors suggest that previous analyses overlooked certain calculations and uncertainties, including the gravitational influence of the Large Magellanic Cloud (a smaller galaxy orbiting the Milky Way).
They also propose that a merger with the Magellanic Clouds is nearly certain within the next two billion years, prior to any potential interaction with Andromeda.
“Even with the latest and most precise observational data at hand, the future of local galaxy groups remains uncertain,” Dr. Sawara remarked.
“Interestingly, there are roughly equal probabilities of widely discussed merger scenarios or, conversely, scenarios where the Milky Way and Andromeda remain unaffected.”
The team’s findings will be featured this week in the journal Nature Astronomy.
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T. Sawara et al. There is no certainty regarding the Milky Way and Andromeda collision. Nature Astronomy. Published online on June 2, 2025. doi:10.1038/s41550-025-02563-1
Source: www.sci.news
