Illustration showing the V906 Carinae nova eruption. V906 Carinae was a white dwarf in the Milky Way constellation Carina. Novas are explosions that occur on the surface of white dwarf stars. In March 2018, astronomers detected shock waves from V906 Carinae. This was caused by ejected material, travelling at different speeds and phases, colliding into each other. These shocks produced optical and gamma ray flares, increasing the luminosity of V906 Carinae.