Death by Dynamics: Planetoid-Induced Explosions on White Dwarfs

Understand

At intervals as short as ten thousand years, each white dwarf (WD) passes within a solar radius of a planetoid, i.e., a comet, asteroid, or planet.

• Gravitational tidal forces tear the planetoid apart; its metal-rich debris falls onto the WD, enriching the atmosphere.
• A third of WDs exhibit atmospheric "pollution".
• For roughly every hundred planetoid disruptions, a planetoid collides with a WD.