Discussing the mysteries surrounding the formation of the Rocky Mountains, one of the world's largest mountain ranges, stretching across 4800 kilometres from the northern tip of British Columbia to the Rio Grande in New Mexico.

Scientists have been exploring Pluto since its discovery in 1930.

How the earth's atmosphere came to be; the one man to have braved the atmosphere's upper reaches and survived.

Ice may have entombed Earth for hundreds of millions of years, spawning the complex animals that evolved in the greenhouse heat wave that followed.