Hanny's Voorwerp is an instance of an astronomical phenomenon called a quasar ionization echo. It was discovered in 2007 by Dutch schoolteacher Hanny van Arkel while she was participating as a volunte
Hannys voorwerp
One hypothesis for how Hanny's Voorwerp was formed
A Hubble Space Telescope combined image of eight quasar ionisation echoes, or Voorwerpjes. CREDITS: NASA, ESA and Prof. William Keel
A Hubble Space Telescope image of the Teacup Galaxy SDSS 1430 +13, a Voorwerpje. CREDITS: NASA, ESA and William Keel