In this lecture we step back and look at the history of life on Earth
from the first signs of life at start of the Archaean Eon 3.5 billion
years ago to just up to the present day. We will review the appearance
of photosynthesis and the rise of oxygen in the atmosphere in the
Proterozoic, the appearance of the first eukaryotes and sexual
reproduction, and t ... Show More
Oct 2009
Lecture 22: The Family of the Sun
This first lecture of Unit 4 - Life in the Solar System - is a quick tour of our Solar System reviewing the planets, dwarf planets, moons, and small bodies that make up our celestial home. This lecture will introduce many of the places we will be considering in detail over the ne ... Show More
46m 22s
<p>La durée de vie d'une étoile peut nous renseigner sur sa composition et sur l'existence éventuelle de la vie dans le cosmos. mais, en dehors du Soleil, il est assez difficile de déterminer l'âge d'une étoile.</p><br><p>L'importance de la masse</p><br><p>En évaluant, grâce à la ... Show More