This interactive magnetar simulation visualises the most powerfully magnetized objects known: neutron stars whose crust periodically fractures in a "starquake," snapping and reconnecting magnetic field lines and unleashing a giant flare of gamma rays.
Magnetars have magnetic fields around 10¹⁴–10¹⁵ gauss, a thousand times stronger than ordinary neutron stars. Immense magnetic stresses build in the rigid crust until it fractures — a starquake — releasing energy that reconfigures field lines and powers a burst of gamma radiation, exactly as this simulation's stress bar, crack animation and flare depict.
Raise the field strength or starquake frequency to speed up how often stress triggers a crack. Increase flare intensity to make eruptions more energetic, and toggle field lines to see the twisted magnetic structure wrapping the star. Use "Force Starquake" to trigger an eruption on demand.
The giant flare from magnetar SGR 1806-20 in 2004 released more energy in a fraction of a second than the Sun emits in 100,000 years, and was detected by satellites and even affected Earth's upper atmosphere from 50,000 light-years away.
Magnetars are a rare class of neutron star possessing the strongest magnetic fields known in the universe, typically 10¹⁴ to 10¹⁵ gauss — enough to strip electrons from atoms at a distance of a thousand kilometres. This simulation renders looping dipole-like field lines around a glowing stellar surface, wound tighter as the field-strength slider increases, and periodically builds up magnetic stress until the rigid crust cracks in a starquake.
When the crust fractures, the twisted magnetic field lines threading it suddenly reconnect, converting magnetic energy into an intense, brief burst of gamma rays — a giant flare. The simulation visualises this as a jagged crack pattern followed by a bright flash and an outward burst of particles, then a fading return to a quiet magnetic configuration, mirroring the observed behaviour of soft gamma repeaters.
Magnetic stress accumulates as field-line tension twists the solid neutron star crust until it exceeds the crust's yield strength, triggering a starquake and magnetic reconnection.
Field strength and starquake frequency control how fast stress builds; flare intensity scales the eruption's particle burst; field-line density lets you see the magnetic structure clearly.
Only a handful of giant flares have ever been observed from the roughly 30 known galactic magnetars, making each one a rare cosmic event.
A magnetar is a type of neutron star with an extraordinarily powerful magnetic field, around a thousand times stronger than a typical neutron star's and roughly a quadrillion times stronger than Earth's. Magnetars form from the collapsed cores of massive stars after a supernova.
A magnetar's intense internal magnetic field exerts enormous stress on its solid crust. When that stress exceeds the crust's structural strength, the crust suddenly fractures — a starquake — similar in concept to an earthquake but driven by magnetic rather than tectonic forces.
The crust fracture jolts the magnetic field lines threading it, which can snap and reconnect in a process that rapidly converts stored magnetic energy into radiation, producing a giant flare of gamma rays and X-rays lasting from a fraction of a second to several minutes.
Magnetar fields are typically 10¹⁴ to 10¹⁵ gauss, compared with about 1 gauss for Earth's field and roughly 10¹²–10¹³ gauss for ordinary pulsars. At close range a magnetar's field could theoretically disrupt the atomic structure of ordinary matter.
Yes. The 27 December 2004 giant flare from SGR 1806-20, roughly 50,000 light-years away, was so intense that its gamma-ray pulse measurably disturbed Earth's ionosphere, despite the source being on the far side of the galaxy.