A hidden population of magnetic stars has been caught erupting in violent bursts that were previously thought to be impossible.
Intermediate Polars are pairs of stars where a white dwarf pulls material from a companion using intense magnetic fields. Standard models predicted these systems shouldn't have sudden outbursts because their magnetic fields clear out the surrounding gas discs. This systematic search found dozens of these events, which may be a new type of eruption called a micronova. These bursts happen quickly and are far more common than anyone realized. This discovery proves that magnetic star systems are much more volatile than our current theories allow.
A Systematic Search for Optical Outbursts in IPs Using ASAS-SN
arXiv · 2604.26468
Cataclysmic variables can show rapid increases in optical flux. Intermediate polars (IPs), a subset with strong magnetic fields that disrupt the inner accretion disc, have been thought to possess truncated discs that rarely undergo the disc-instability outbursts seen in dwarf novae. However, the discovery of micronovae and magnetic-gating bursts suggests that such events may occur even without a fully developed disc. Using data from the All-Sky Automated Survey for Supernovae (ASAS-SN), we ident