This book explores how planetary systems form and change, with most of its discussion focused on the Solar System. It covers the formation of planets and the Earth-Moon system, shifting orbits, asteroid and icy-body belts, and the movement of dust. I...

WASP-4 c, a distant giant companion to the hot Jupiter WASP-4 b, has a minimum mass of 9.3 Jupiter masses and an orbital period of about 29 years. Combining measurements of stellar motion, planet transits and the star’s position on the sky also fin...