The Apollo equipment has sat abandoned on the lunar surface for over 40 years. Now there is a renewed excitement and drive to return to the moon. This time, not to just plant a flag, but to colonize. How would we accomplish this? And why would we do it?
Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into helium, and eventually helium into carbon (and also some oxygen and neon). When this happens they expand, get brighter, and cool off, becoming red giants. They lose most of their mass, exposing their cores, and then cool off over many billions of years.
The worlds that surround our planet are all made of rock, but there the similarity ends. Some have a beating geological heart, others are frozen in time. Professor Brian Cox travels to the tallest mountain on Earth, the volcano Mauna Kea on Hawaii, to show how something as basic as a planet's size can make the difference between life and death.
Untangling Alzheimer's is a dramatic and inspiring medical investigation driven by David Suzuki's journey to understand the science of Alzheimer's and the surprising new insights into its cause. David has a very personal interest in the disease because his mother, aunt and two uncles died of it. We join David on an intimate journey as he explores the newest breakthroughs in this devastating disease as well as his own chances of contracting the cruel condition. Alzheimer's today is the only leading cause of death that cannot be cured, prevented or even slowed. Worse, it's the only leading cause of death that is on the rise – and not simply because baby-boomers are getting older. Studies show that the increase is absolute across all age groups, and death rates continue to climb. With a new case developing every 69 seconds, scientists now speak of the Alzheimer's epidemic.