The four large Galilean Moons of Jupiter seem unlikely places to look
for life; at first glance they should be cold, dead, icy worlds.
Instead we find tremendous geological diversity, and two big surprises:
volcanically-active Io, and icy Europa. Io is the most volcanically
active world in the Solar System, heated by tides from Jupiter. Europa
is even mor ... Show More
Sep 2009
Lecture 2: Astronomical Numbers
An introduction and review of the basic notation and physical units we will be
using throughout this course. In particular, we will be using the
Metric (SI) system for lengths, masses, times, and temperatures, and
special astronomical units for distances (AU and Light Years) and ... Show More
43m 56s
<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
