All articles tagged with #local group
Researchers using computer simulations reveal the Local Group sits in a vast, flat sheet of matter—dominated by dark matter—with large voids above and below. This structure counteracts the Milky Way–Andromeda gravity, causing nearby galaxies to recede rather than fall inward and producing a virtual twin of our cosmic neighborhood that matches the observed positions and speeds of galaxies just outside the Local Group.
A new Nature Astronomy study using constrained, Lambda-CDM–based simulations finds the Local Group’s unseen mass is arranged not in a spherical halo but in a flattened dark matter plane tens of millions of light-years across. This geometry better reproduces the observed motions of nearby galaxies and the local Hubble flow, reducing discrepancies seen in spherical models while remaining consistent with overall cosmology. The result highlights how the dark matter around us likely forms sheets and filaments in the cosmic web, though more data is needed to pin down the plane’s thickness and orientation.
A Nature Astronomy study finds that a vast, flat sheet of dark matter surrounding the Milky Way and Andromeda reshapes local gravity, slowing the motion of closer galaxies and accelerating more distant ones, which explains why Andromeda is on a collision course with the Milky Way and underscores dark matter’s key role in the dynamics of our cosmic neighborhood.
A Nature Astronomy study using local-universe simulations finds a vast, flat sheet of dark matter surrounding the Local Group that counteracts the Milky Way–Andromeda attraction. This sheet’s gravity pulls nearby galaxies outward, explaining why Andromeda is approaching us while other nearby galaxies are receding with cosmic expansion, reconciling observations with the standard cosmological model.
New simulations suggest the Milky Way sits within a flat, sheet-like dark matter structure spanning tens of millions of light-years, damping inbound galaxy motions and solving long-standing mass and velocity discrepancies that spherical models could not explain. The sheet aligns with the Supergalactic Plane and implies a higher Local Group mass (~3.3 ± 0.6 trillion solar masses) within a broader anisotropic dark matter geometry that shapes the nearby cosmos and possibly early-universe structure.
A Nature Astronomy study using a virtual twin of the Local Group proposes that the Milky Way and its neighboring galaxies are embedded in a vast, sheet-like distribution of dark matter bordered by cosmic voids. This flat geometry could explain peculiar motions that spherical dark matter halos struggle to account for, with simulations aligning with observed galaxy dynamics.
A Nature Astronomy study proposes that the Milky Way and its Local Group are embedded in a gigantic flat sheet of dark matter, with mass concentrated at the sheet's edges and voids beyond. Using a simulated “virtual twin” of the group, the researchers show this geometry can explain peculiar motions that spherical halos can't, aligning local dynamics with the broader cosmological model and offering the first assessment of dark matter distribution in our neighborhood.
A Nature Astronomy study suggests the Milky Way and its Local Group reside in a vast, flat sheet of dark matter flanked by cosmic voids. This geometry helps explain the unusual motions of nearby galaxies, including Andromeda’s approach, and offers a new perspective on how dark matter structures shape local cosmology.
The Milky Way and Andromeda galaxies, the two largest in the Local Group, orbit a common center of mass and are on mostly radial orbits toward each other. This will eventually lead to a collision and merger into a single elliptical galaxy in about 4.5 billion years. The Local Group is also moving towards the Virgo Cluster, but will not reach it due to the universe's expansion.
A recent study summarizes the various methods used to determine the mass of the Milky Way, including measuring the motion of stars, globular clusters, satellite galaxies, tidal plumes of dwarf galaxies, and stars leaving our galaxy. The team took a statistical average of these methods and determined the best value for the mass of our galaxy to be a trillion solar masses, give or take a few hundred billion solar masses.
Using cosmological simulations, an international team predicts that there may be up to 12 ultra-diffuse galaxies in the Local Group, a small cluster that currently contains approximately 60 known galaxies, including the Milky Way and Andromeda. Ultra-diffuse galaxies are faint and difficult to observe, but understanding their total number in the Local Group is crucial to our understanding of the cosmos. The discovery of these new galaxies could have far-reaching implications for our understanding of galaxy formation and evolution.