Now that the Space Shuttle Endeavor has lifted off and is scheduled to dock tomorrow with the International Space Station, plans are back on for Pope Benedict XVI to chat with the astronauts. Jesuit Father Federico Lombardi, Vatican spokesman, said that the pope’s audiovisual satellite linkup with the space station is scheduled for 1:56 p.m. Rome time Saturday. The conversation originally was scheduled for May 4, but the Endeavor's liftoff was delayed. The papal linkup was organized by the European Space Agency, which has one Italian on the Endeavor and one Italian already on the space station. Both crews will be in the space station when the pope calls. Even though it is in the nature of every human being to seek God, creating the kind of inner state necessary for prayer is difficult, Pope Benedict XVI said. "Prayer is first and foremost a matter of the heart where we experience God's call and our dependence on his help to transcend our limitations and sinfulness," the pope said at his weekly general audience. Pope Benedict's catechesis was the latest in a new series of audience talks about prayer. Prayer is an inner activity, "a way of being before God," and not a series of formulas, words and gestures, he said. Because prayer is rooted so deeply in the individual's inner being, it is "not easily decipherable" and is "difficult," he said. Prayer is a privileged moment for self-giving and putting oneself before "the invisible, the unexpected, the ineffable," and for that reason "the experience of prayer is a challenge for everybody, a grace to be invoked and a gift" from God, he said. Despite the current climate of secularism in which God is overlooked or eliminated from one's life, there are also "many signs that tell us there is a reawakening of the religious sense, a rediscovery of the importance of God" in people's lives, the pope said. The prediction that humanity would gain freedom, dignity and autonomy by replacing religion with pure reason "has failed" and the two World Wars from the past century have severely tested the belief that reason bereft of God would bring progress, he said.