Today there were major developments in three global hotspots: the nuclear agreement in Iran, a horrific attack on a university in Kenya., and a big blow struck against ISIS. Our global caucus, made up of some of the top international experts in the region, takes up all those issues. Jim Walsh ( @DrJimWalshMIT) is an international security researcher at MIT, Boston University Professor  Farouk El-Baz worked for years at NASA and as an advisor to Egypt's presidents, and Jessica Stern ( @JessicaEStern) lectures about terrorism at Harvard and recently co-authored "ISIS: The State of Terror."

With so much focus on the mental health of the Germanwings co-pilot, we look to set the record straight on the facts of depression with National Alliance on Mental Illness Medical Director Dr. Ken Duckworth and Harvard Medical School Associate Professor of Psychiatry Dr. Nancy Rappaport.

Over the past several years, telescopes have been picking up mysterious radio wave flashes, apparently from far outside our galaxy. Some scientists are seriously asking whether they might be from some sort of out-of-this-world technology.  Kelly Beatty ( @NightSkyGuy), senior editor at Sky and Telescope magazine, assured us that it's not aliens.

College basketball’s Final Four tips off this weekend. Jim look at the real March Madness: how success on the court is surely not matched with success in the classroom, and the schools seem not to care.