... , convective heating causes cells of ionised metal to rise and fall in a circular motion. These act like gigantic electrical currents, which in turn generate the magnetic field in the same way that a current circulating in coils of wire does. The Ear ...

... in greenhouse gases. This kept the surface warm enough for some liquid water, despite the Sun only emitting some 70% of its current energy output. Despite these hellish conditions, life began on Earth during the Archaean Eon. ...

... in greenhouse gases. This kept the surface warm enough for some liquid water, despite the Sun only emitting some 70% of its current energy output. Despite these hellish conditions, life began on Earth during the Archaean Eon. ...

Graphic depicting the current number of natural satellites known to orbit each of the eight major planets (as for October 2021). Mercy and Venus have no satellites; Earth has one; Mars has two; Jupiter has 79; Saturn has the lion's share at 81; Uranu...

Graphic depicting the current number of natural satellites known to orbit each of the eight major planets (as for October 2021). Mercy and Venus have no satellites; Earth has one; Mars has two; Jupiter has 79; Saturn has the lion's share at 81; Uranu...

Diagram comparing the Sun with Stephenson 2-18. The latter is the current contender for the largest known star, a red hypergiant some 2150 times the diameter of the Sun. The Sun can fit into it 10 billion times!...