Scientists Reflect on Expected Collision Between the Milky Way and the Andromeda Galaxy

Crash of the Titans: Andromeda Galaxy and the Milky Way Collision

This photo illustration depicts a view of the night sky just before the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy. About 3.75 billion years from now, Andromeda's disk fills the field of view and its gravity begins to create tidal...

Nighttime Sky View of Future Galaxy Merger

This series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. The sequence is inspired by dynamical computer modeling of the inevitable future collision...

Nighttime Sky View of Future Galaxy Merger: Present Day

This is a nighttime view of the current sky, with the bright belt of our Milky Way. The Andromeda galaxy lies 2.5 million light-years away and looks like a faint spindle, several times the diameter of the full Moon.

Nighttime Sky View of Future Galaxy Merger: 2 Billion Years

The disk of the approaching Andromeda galaxy is noticeably larger.

Nighttime Sky View of Future Galaxy Merger: 3.75 Billion Years

Andromeda fills the field of view. The Milky Way begins to show distortion due to tidal pull from Andromeda.

Nighttime Sky View of Future Galaxy Merger: 3.85-3.9 Billion Years

During the first close approach, the sky is ablaze with new star formation, which is evident in a plethora of emission nebulae and open young star clusters.

Nighttime Sky View of Future Galaxy Merger: 3.85-3.9 Billion Years

During the first close approach, the sky is ablaze with new star formation, which is evident in a plethora of emission nebulae and open young star clusters.

Nighttime Sky View of Future Galaxy Merger: 4 Billion Years

After its first close pass, Andromeda is tidally stretched out. The Milky Way, too, becomes warped.

Nighttime Sky View of Future Galaxy Merger: 5.1 Billion Years

During the second close passage, the cores of the Milky Way and Andromeda appear as a pair of bright lobes. Star-forming nebulae are much less prominent because the interstellar gas and dust has been significantly decreased by previous bursts of star formation.

Nighttime Sky View of Future Galaxy Merger: 7 Billion Years

The merged galaxies form a huge elliptical galaxy, its bright core dominating the nighttime sky. Scoured of dust and gas, the newly merged elliptical galaxy no longer makes stars and no nebulae appear in the sky. The aging starry population is no longer concentrated along a...

Halo of Andromeda Galaxy Used to Measure Its Drift Across Space

This composite image shows a region in the halo in the neighboring Andromeda galaxy that astronomers used to precisely measure the galaxy's sideways motion on the sky. This has allowed them to predict a direct collision between Andromeda and the Milky Way about 4 billion years...

Measuring the Drift of the Andromeda Galaxy

This illustration shows one of the regions in the neighboring Andromeda galaxy where astronomers aimed the Hubble Space Telescope to make precise measurements of the galaxy's lateral motion. As the galaxy drifts through space, the stars will appear to uniformly move against the...

Collision Scenario for Milky Way and Andromeda Galaxy Encounter

This illustration shows the inevitable collision between our Milky Way galaxy and the Andromeda galaxy approximately 4 billion years from now. The galaxies are moving toward each other under the inexorable pull of gravity between them. A smaller galaxy, Triangulum, may be part...

Fate of Sun After Galaxy Collision

This illustration is a before-and-after comparison of the size of our Milky Way galaxy at present, and after it fully completes a merger with the neighboring Andromeda galaxy 10 billion years from now. The merged galaxies will blend together to create an elliptical galaxy of...

Compass and Scale Image of Andromeda

Crash of the Titans Science Visualization (Annotated)

This scientific visualization of a computer simulation depicts the inevitable collision between our Milky Way galaxy and the Andromeda galaxy (also known as Messier 31). NASA Hubble Space Telescope observations indicate that the two galaxies, pulled together by their mutual...

Crash of the Titans Science Visualization

This scientific visualization of a computer simulation depicts the inevitable collision between our Milky Way galaxy and the Andromeda galaxy (also known as Messier 31). NASA Hubble Space Telescope observations indicate that the two galaxies, pulled together by their mutual...

Nighttime Sky View of Future Galaxy Merger (Annotated)

This video series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. The sequence is inspired by dynamical computer modeling of the inevitable future...

Nighttime Sky View of Future Galaxy Merger

This video series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. The sequence is inspired by dynamical computer modeling of the inevitable future...

Nighttime Sky View of Future Galaxy Merger (Annotated, With Holds)

This video series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. The sequence is inspired by dynamical computer modeling of the inevitable future...

Nighttime Sky View of Future Galaxy Merger (With Holds)

This video series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. The sequence is inspired by dynamical computer modeling of the inevitable future...

Measuring the Drift of the Andromeda Galaxy (Annotated)

This video zooms into a region in the halo of the neighboring Andromeda galaxy that astronomers studied with the Hubble Space Telescope to make precise measurements of the galaxy's motion. Andromeda was previously known to be approaching the Milky Way, but these new measurements...

Measuring the Drift of the Andromeda Galaxy

This video zooms into a region in the halo of the neighboring Andromeda galaxy that astronomers studied with the Hubble Space Telescope to make precise measurements of the galaxy's motion. Andromeda was previously known to be approaching the Milky Way, but these new measurements...

The Fate of the Milky Way, Andromeda, and Triangulum Galaxies (Annotated)

The three largest galaxies in our Local Group of Galaxies are our Milky Way along with the Andromeda (also known as Messier 31) and Triangulum (also known as Messier 33) galaxies. This scientific visualization of a computer simulation depicts their joint evolution over the next...

The Fate of the Milky Way, Andromeda, and Triangulum Galaxies

The three largest galaxies in our Local Group of Galaxies are our Milky Way along with the Andromeda (also known as Messier 31) and Triangulum (also known as Messier 33) galaxies. This scientific visualization of a computer simulation depicts their joint evolution over the next...