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 empire on which the sun never sets Sam". In 1906, William Jennings Bryan wrote, "If we can not boast that the sun never sets on American territory, we can find satisfaction in the fact that the sun never sets on American philanthropy"; after which, "The New York Times" received letters attempting to disprove his presupposition. A 1991 history book discussion of U.S. expansion states, "Today ... the sun never sets on American territory, properties owned by the U.S. government and its citizens, American armed forces abroad, or countries that conduct their affairs within limits largely defined by American power." Although most of these sentiments have a patriotic