Humanitarian Crises and Community Challenges

People from around the world descended on Saint Peter's Square this morning for the inaugural mass of Pope Leo XVI. World leaders also attended the event, including Canadian Prime Minister Mark Carney. The more than two hour long event featured song, symbolism and a message of Peace. We'll take you to The Vatican for the day's events.

Also: Former U.S. President Joe Biden has been diagnosed with an aggressive form of prostate cancer. Our Washington bureau has more details.

And: 45 years ago today, ash rained down on parts of western Canada, as Mount Saint Helens erupted near Seattle. Dozens of people were killed, and scientists say it's going to happen again. But this time - new technology could people prepare for an predict future eruptions.

Plus: Three children killed in Toronto car crash, the "shrubification" destroying Arctic ecosystems, and more.