A recent dazzling explosion in a distant galaxy has led astronomers to uncover the first-ever magnetic star located beyond our Milky Way. This discovery opens up the possibility of the existence of numerous similar stars in the universe, awaiting exploration. The newly identified magnetar, a relic of a former bright star with an exceptionally potent magnetic field, inhabits the galaxy M82, known as the Cigar Galaxy, situated roughly 12 million light-years away from Earth. Scientists observed this ultramagnetic star using a telescope from the European Space Agency (ESA) after it underwent a violent eruption, emitting intense energy for a brief moment, as detailed in a new study published in the journal Nature.
Magnetars, often referred to as the universe’s most powerful magnets, are rapidly rotating, highly magnetized versions of neutron stars – remnants of supernova explosions that shine thousands of times brighter than the sun. These stars, however, are challenging to study due to the short-lived and unpredictable nature of their eruptions. With only three other magnetar flares recorded in the past half-century, this latest discovery paves the way for investigating more extragalactic magnetars, offering valuable insights into their frequency of flares and energy dissipation processes, according to ESA researcher Ashley Chrimes.
In mid-November 2023, the Integral space telescope from ESA detected a sudden burst of gamma-rays in the direction of M82, signaling a unique astronomical event. Further observations pinpointed the source of the burst within M82, revealing characteristics distinct from typical gamma-ray bursts associated with phenomena like black hole formations or neutron star mergers. Instead, astronomers found evidence of a magnetar eruption through the presence of hot gas and stars, confirming the starquake hypothesis where a magnetar’s magnetic fields disrupt its spin and surface layers, leading to the emission of energetic gamma-rays across the cosmos.
The study’s lead author, Sandro Mereghetti, emphasized the significance of the burst’s origin in a nearby galaxy, underscoring the exceptional nature of the discovery. The follow-up investigations with various telescopes reaffirmed the magnetar’s presence and shed light on the distinct mechanisms behind such phenomena. This newfound extragalactic magnetar expands the limited roster of magnetars previously identified within our own galaxy, offering astronomers a broader scope for understanding these enigmatic celestial objects and their cosmic implications.
The unique attributes of this newfound magnetar have provided researchers with valuable insights into the processes governing these fascinating stars, shedding light on their behavior and energy dynamics. As the search for extragalactic magnetars continues, astronomers anticipate uncovering more of these magnetic stars across different galaxies, enhancing our understanding of their role in cosmic phenomena. With each discovery, the intricate tapestry of the universe unravels further, offering a glimpse into the mysteries of the cosmos beyond our familiar Milky Way.
