The letter about Fred Hoyle and panspermia (April 22) may have given readers the impression that Hoyle invented the idea that life came to Earth from space. This idea has a long history. The word "panspermia" was coined by the Swedish scientist Arrhenius in the 1900s. While some areas of panspermia are still controversial, the idea that under the right conditions life could have hitchhiked a ride to Earth on a Martian meteorite, for example, is not implausible (although this requires life on Mars in the first place).
Mark Burchell
Kent