The status of Pluto not withstanding, our solar system has 8 planets, but one astronomer believes we used to have a ninth ...

Ancient grains inside one of the oldest known meteorites reveal that a surprisingly strong magnetic field existed during the solar system’s first 200,000 years. The discovery suggests magnetism worked ...

Iron meteorites show the first bodies of the early solar system were 83% to 92% dry rock, with water arriving millions of ...