Fifteen years following the first discoveries, about 230 extra solar planet (exoplanet) candidates are known. Most of them are hosted by core hydrogen burning main sequence stars similar to our Sun, although a few planets orbiting red giant stars have been recently found. When their core hydrogen runs out, main sequence stars undergo a red giant expansion that modifies the planetary orbits and can easily reach and engulf the inner planets. The same will happen to the planets of our solar system in about 5 Gyr and the fate of the Earth is matter of debate.

Here I report the first detection of a planetary-mass body orbiting an horizontal branch, core helium burning, pulsating star at a distance of about 1.7 AU, with a period of 3.2 yr.