Carol Glatz

Astronomers construct and play with a variety of mathematical models, and one popular model looks at how likely it is that civilizations on different planets could end up contacting each other. Scientists have proposed various simulations and predictions, and now a Jesuit astronomer and former director of the Vatican Observatory has co-authored a study offering a new set of results.

For peace to flourish, weapons of war must be set aside, especially nuclear weapons that can obliterate entire cities and countries, Pope Francis said on the 75th anniversary of the nuclear bombing of Hiroshima.

Human health, peace, security and progress would be better served with a complete end to the production of weapons worldwide, said members of a Vatican task force.