The stars at night are only a fraction of what we know should be there. So where are all those missing bits from our universe? This is a lifelong quest for Professor James Green from Colorado University in Boulder. Since his student days, he has been designing payloads for NASA rockets (and the Hubble space telescope) looking at invisible stuff. So how do you see in the cold black soup of space? What is a Sounding Rocket? Why do Wimps beat Macho's ? These and many more questions are answered in Dr Karl's latest podcast.