All articles tagged with #supernovae
Astronomers monitoring the red supergiant WOH G64 in the Large Magellanic Cloud report a rapid evolution into a yellow hypergiant, with a temperature rise of about 1,000 C and significant shrinking. This rare color and size change may signal an impending supernova, though researchers offer two possible explanations—binary interaction with a companion or a prior eruptive episode—and the star’s exact fate remains uncertain.
A new paper by Slava Turyshev argues that small systematic biases in how we measure supernova brightness and the standard ruler set by baryon acoustic oscillations could explain the DESI DR2–CMB mismatch, potentially removing the case for evolving dark energy. He also advocates the Alcock-Paczynski diagnostic to reduce dependence on early-universe benchmarks and outlines scenarios like the Late-Transition Interacting Thawer (LTIT) and Phantom Crossing as alternative explanations, with upcoming data from Euclid expected to test these ideas.
A new study suggests that the universe's expansion may be slowing down rather than accelerating, challenging the current understanding of dark energy, by revealing that the brightness of Type Ia supernovae correlates with the age of their host galaxies, which could bias previous measurements of cosmic expansion.
A recent study suggests that the universe's expansion is slowing down rather than accelerating, challenging the standard cosmological model and implying potential new physics or models like a cyclic universe. The findings focus on the impact of progenitor star age on Type Ia supernova luminosity, which could bias previous measurements of cosmic expansion. While intriguing, the results are met with cautious skepticism and require further validation with upcoming data.
A new study suggests that the universe's expansion is slowing down rather than accelerating, challenging the long-held belief that dark energy is causing an ever-increasing expansion rate. The findings indicate that dark energy may weaken over time, leading to a transition from acceleration to deceleration, which could significantly alter our understanding of the universe's past and future.
A recent study suggests that ancient Arabic texts may contain references to two significant supernovae observed in 1006 and 1181 AD, providing new insights into historical astronomical observations and their potential locations in the sky.
Cosmic dust, composed mainly of small particles of silicates, ices, and metals, originates from processes like supernova explosions, stellar outflows, and planetary nebulae, but the primary source of the universe's dust appears to be core-collapse supernovae, which produce large amounts of dust that can survive destructive processes, playing a crucial role in star and planet formation.
NASA's Roman Space Telescope, set to launch by 2027, will conduct surveys to detect distant supernovae and transient objects, helping scientists trace the universe's expansion and study dark energy, especially focusing on the early universe and its evolution over time.
Recent observations using the eROSITA telescope have revealed that the Local Hot Bubble surrounding our solar system is an irregular, dynamic structure shaped by multiple supernova explosions and possibly connected to other galactic features through interstellar tunnels, providing new insights into the active and interconnected nature of our galaxy's environment.
A new, large standardized dataset of over 2,000 Type Ia supernovae suggests that dark energy, which drives the universe's accelerated expansion, may be evolving over time, challenging the current Lambda CDM model. While not conclusive, these findings, supported by multiple independent studies, could have significant implications for understanding the universe's fate.
NASA's upcoming Roman Space Telescope, set to launch by May 2027, is expected to discover up to 100,000 cosmic explosions, including supernovas, kilonovas, and black hole events, which will help scientists understand dark energy, stellar life cycles, and the origins of heavy elements. The telescope's high-cadence survey will create cosmic movies over two years, vastly expanding our knowledge of the universe's most violent phenomena.
NASA's upcoming Roman Space Telescope is expected to discover around 100,000 cosmic explosions, including supernovae, black hole events, and possibly the first stars, significantly advancing our understanding of the universe's history, dark energy, and black hole physics.
Research suggests that supernova explosions may have caused abrupt climate shifts in Earth's past by affecting the atmosphere, and understanding these effects could help predict future climate events, especially as nearby supernovae like Betelgeuse's explosion could impact Earth.
A recent study challenges the existence of dark energy, proposing the timescape cosmology model as an alternative explanation for the Universe's accelerated expansion, based on new observational data and refined analysis techniques.
A new study suggests that supernova remnants can temporarily become the universe's most powerful particle accelerators, called PeVatrons, capable of producing ultra-energetic cosmic rays. This phase is brief, lasting only a few months, which explains why direct detections are rare despite frequent supernovae in the Milky Way. The key factor is the dense gas shell around the star, which, when hit by the explosion, creates intense magnetic fields that accelerate particles to PeV energies.