Study Keeps Dark Matter in Play for Milky Way Gamma-Ray Excess, Raising Pulsar Estimate Above 35,000
Updated
Updated · Space.com · Jun 21
Study Keeps Dark Matter in Play for Milky Way Gamma-Ray Excess, Raising Pulsar Estimate Above 35,000
3 articles · Updated · Space.com · Jun 21
Summary
More than 1 million simulated gamma-ray observations in a new machine-learning analysis failed to rule out self-annihilating dark matter as the source of the Milky Way’s Galactic Center Excess.
The study found any unresolved point sources in the crowded galactic core would have to be extremely faint, making them hard to distinguish from the gamma-ray signal expected from dark matter annihilation.
Above 35,000 pulsars would be needed to explain the excess under that scenario, far more than earlier estimates that suggested a few hundred could suffice.
The result keeps alive one of astrophysics’ longest-running debates rather than settling it: dark matter makes up about 85% of the universe’s matter, but the new paper stops short of claiming it caused the glow.
Why are top scientists claiming our galaxy's core is lit by both dark matter and thousands of dead stars?
Is the mysterious glow at our galaxy's heart the first real glimpse of dark matter annihilating itself?
Galactic Center Gamma-Ray Excess: 2026 Machine Learning Study Weakens Pulsar Hypothesis, Boosts Dark Matter Case
Overview
The Galactic Center Excess (GCE) is a mysterious surplus of gamma-rays coming from the Milky Way’s core, puzzling scientists for years. Two main ideas compete to explain it: one suggests the GCE is caused by dark matter particles annihilating and producing gamma-rays, while the other points to a population of unresolved millisecond pulsars (MSPs), whose combined faint emissions could mimic a diffuse glow. However, new machine learning studies now challenge the pulsar explanation, making it harder to distinguish their collective signal from that expected of dark matter, and bringing the dark matter hypothesis back into focus.