Did early Earth spin on its side?

1 November 2016 Astronomy Now

New theoretical modelling of the ancient history of the Earth and the Moon suggests that the giant collision that spawned our natural satellite may have left Earth spinning very fast, and with its spin axis highly tilted. The simulations give new insight into the question of whether planets with big moons are more likely to have moderate climates and life.


Moon was produced by head-on collision between Earth and forming planet

29 January 2016 Astronomy Now

The Moon was formed by a violent, head-on collision between the early Earth and a “planetary embryo” called Theia (pronounced THAY-eh) approximately 100 million years after the Earth formed, UCLA scientists reveal. This new research also refutes the work of a team of German scientists who, in 2014, reported that the Moon also has its own unique ratio of oxygen isotopes, different from Earth’s.


A new view of the Moon’s formation

8 April 2015 Astronomy Now

A crucial difference in the isotopic chemical “fingerprints” of Earth and the Moon confirms an explosive, interconnected past when, within the first 150 million years after our Solar System formed, a giant body roughly the size of Mars struck the Earth.