An exotic green comet that has not passed Earth since the time of the Neanderthals has reappeared in the sky ready for its closest approach to the planet next week.
Discovered last March by astronomers at the Zwicky Transient Facility at the Palomar Observatory in California, comet C/2022 E3 (ZTF) was calculated to orbit the sun every 50,000 years, meaning it last tore past our home planet in the stone age.
