Astronomers find zombie planets around a dead star 1,600 light-years away

A double debris disc with a clear gap around white dwarf J1328−1450 hints at two surviving planetesimals, one asteroid-sized and one between the moon and Pluto in size. The debris contains calcium, oxygen, magnesium and iron, resembling rocky inner-solar-system planets. The system offers a preview of our solar system's fate after the sun dies.

• White dwarf J1328−1450 lies about 1,600 light-years from Earth
• Remnants range from asteroid size to between the moon and Pluto
• Discs contain calcium, oxygen, magnesium and iron
• The sun will become a red giant in about 5 billion years