The Russian Soyuz capsule with three crew members on board has landed safely this morning on the Kazakh steppe. The Mission Control center outside Moscow said the landing was smooth. The return flight of the Soyuz TMA-18 brought down to earth Russian astronauts Alexander Skvortsov and Mikhail Korniyenko, and NASA astronaut Tracy Caldwell-Dyson. The undocking of the spacecraft from the International Space Station was delayed on Friday for 24 hours due to a false alarm signal sent by an airlock sensor.