Accidental discovery reveals 'millinovas,' a new class of cosmic explosion 100 times brighter than the sun

Dec 23, 2024

'Millinovas' are 100 times brighter than the sun, revealed by OGLE data in LMC and SMC.

Accidental discovery reveals 'millinovas,' a new class of cosmic explosion 100 times brighter than the sun

: A serendipitous discovery led astronomers to identify 'millinovas', a novel class of cosmic explosions that shine 100 times brighter than the sun. Using data from the Optical Gravitational Lensing Experiment (OGLE), these millinovas were observed in the Large and Small Magellanic Clouds, two neighboring galaxies. Researchers believe these events occur when white dwarfs siphon material from nearby swollen stars. The study's findings, detailed in the Astrophysical Journal Letters, illuminate potential mechanisms and significance of these phenomena.

During an examination of 20 years of data from the Optical Gravitational Lensing Experiment (OGLE), a new type of cosmic explosion called 'millinovas' was discovered. Millinovas have been identified in the Large Magellanic Cloud and the Small Magellanic Cloud, with 28 detected so far, each shining 100 times brighter than the sun.

The events are theorized to occur when white dwarfs absorb material from a companion star that has expanded. This novel class of explosions was first observed incidentally, sparking interest due to their potential to serve as Type Ia supernova precursors.

Astronomers used NASA's Neil Gehrels Swift Observatory to confirm the presence of X-rays emitted by millinovas. Published in the Astrophysical Journal Letters, these findings contribute essential insights into the life cycles of stars and the forces shaping our universe.