NASA’s Fermi Telescope Reveals New Gamma-Ray Phenomena in Extragalactic Space
Astronomers examining gamma rays have identified a perplexing phenomenon located just beyond the boundaries of our Milky Way galaxy.
Published on Wednesday in The Astrophysical Journal Letters, the research was presented by Alexander Kashlinsky, a cosmologist affiliated with the University of Maryland and NASA’s Goddard Space Flight Center in Greenbelt, during the 243rd meeting of the American Astronomical Society in New Orleans.
This mysterious occurrence challenges previous understanding, particularly in relation to the cosmic microwave background (CMB), believed to have originated shortly after the Big Bang.
As the universe expanded, the initial burst of light, detected as faint microwaves in 1965, underwent a stretching process over 13 billion years.
The ’70s revealed a dipole structure in the CMB, exhibiting opposite charges at two ends.
Notably, the constellation Leo showed a slight elevation in temperature with more microwaves, while the opposite direction displayed a corresponding drop in temperature and microwaves.
While traditionally attributed to the solar system’s movement relative to the CMB, scientists sought to corroborate or challenge this theory by analyzing other forms of light, including gamma rays.
Gamma-Ray Discovery Questions Cosmic Background
Fernando Atrio-Barandela, a theoretical physics professor at the University of Salamanca in Spain, focused on the importance of these measurements, indicating that studying the discrepancies in the CMB dipole could offer valuable insights into the processes of the early universe.
Combining 13 years of gamma ray data from NASA’s Fermi Large Area Telescope, the research team observed a gamma-ray dipole.
However, its peak diverged from the CMB’s location, situated in the southern sky and displaying a significantly higher magnitude than solar system movement could explain.
Co-author Chris Shrader, an astrophysicist at the Catholic University of America in Washington and Goddard, acknowledged the unexpected findings, hinting at a potential connection with a similar phenomenon observed in 2017 by the Pierre Auger Observatory in Argentina.
This earlier discovery unveiled a dipole peak in ultrahigh-energy cosmic rays, aligning with the gamma-ray peak.
While the correlation suggests a link between the two phenomena, scientists are still unraveling the mystery of an unidentified source responsible for both gamma rays and ultrahigh-energy particles. The ongoing investigation seeks to shed light on this enigmatic cosmic connection.