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Scientists Uncover First Direct Glimpse of Elusive Dark Matter, Decades After Prediction
In a groundbreaking discovery, scientists announced they have for the first time directly observed dark matter, a mysterious substance whose existence was predicted over a century ago. This monumental achievement, detailed in the Journal of Cosmology and Astroparticle Physics, marks a significant leap in our understanding of the universe’s fundamental building blocks.
For years, astronomers have indirectly inferred the presence of dark matter through its gravitational effects on visible matter. Now, utilizing data from NASA’s Fermi Gamma-ray Space Telescope, researchers have managed to detect dark matter itself by identifying gamma rays produced when dark matter particles collide and annihilate.
Dark matter was initially theorized by Swiss astronomer Fritz Zwicky, who proposed it as an invisible “scaffolding” holding galaxies together, enabling them to move at speeds far exceeding what their observable mass would allow.
The research team sifted through a decade and a half of data from the Fermi telescope, focusing on the center of the Milky Way galaxy. Their efforts paid off with the detection of gamma rays exhibiting a photon energy of 20 gigaelectronvolts, or 20 billion electronvolts, emanating from a halo-like structure surrounding the galactic core.
“The gamma-ray emission component closely matches the shape expected from the dark matter halo,” stated Tomonori Totani, a professor at the University of Tokyo’s Department of Astronomy and lead author of the study, in a university press release.
Scientists have long hypothesized that dark matter consists of weakly interacting massive particles, or WIMPs, which typically do not interact with other matter. However, theoretical models predicted that when WIMPs collide, they would annihilate each other, releasing other particles, including gamma-ray photons.
The gamma-ray emissions detected in the Milky Way’s halo closely align with these predictions for WIMP collisions, showing a mass approximately 500 times that of a proton and at an intensity consistent with theoretical models. Totani emphasized that these findings are unlikely to be explained by conventional astronomical or gamma-ray phenomena, strongly suggesting the direct detection of dark matter.
“If this is correct, to the extent of my knowledge, it would mark the first time humanity has ‘seen’ dark matter,” Totani remarked. “It turns out that dark matter is a new particle not included in the current standard model of particle physics. This signifies a major development in astronomy and physics.”