Planet smallest known planet is PSR B1257+12A, one of the first extrasolar planets discovered, which was found in 1992 in orbit around a pulsar. Its mass is roughly half that of the planet Mercury. The smallest known planet orbiting a main-sequence star other than the Sun is Kepler-37b, with a mass (and radius) slightly higher than that of the Moon. Every planet began its existence in an entirely fluid state; in early formation, the denser, heavier materials sank to the centre, leaving the lighter materials near the surface. Each therefore has a differentiated interior consisting of a dense planetary core surrounded
The Message to the Planet The Message to the Planet The Message to the Planet is a novel by Iris Murdoch. Published in 1989, it was her twenty-fourth novel. "The Message to the Planet" centres on Marcus Vallar, a charismatic former mathematician and painter who has abandoned both these pursuits, and on a group of London friends, former associates of Vallar, with whom he has broken off contact. The plot begins with the decision of Alfred Ludens, a young history professor, to seek out his former mentor Vallar in the hope that he can restore his friend Patrick Fenman to health. Fenman is apparently dying