Hi Roger
They're podcasts from the
W M Keck Observatory Podcast Page. I only discovered these yesterday, and listened to a couple on the way home yesterday and on the way in this morning.
Specifically:
-
Where do Planets come from?
and
-
A Sharper Image - Adaptive Optics Leads the Way
There's PDF notes for each of those if you follow the first link. The links above are direct to the mp3. The podcasts are about 50mins in duration.