While the universe eventually will come to a "cold and dark" demise billions of years from now, Christians know that God is always with his creation and welcomes everyone to eternal life, said Jesuit Father Jose Funes, the head of the Vatican Observatory.
The Vatican newspaper, L'Osservatore Romano, published the priest-astronomer's article Dec. 12 under the headline "The end that won't come -- at least for now."
He said the claims that the end of the Mayan "Long Count" calendar Dec. 21 marks the end of the world were "irrational," however, science offers more probable scenarios than pseudo prophesies do.
Discoveries suggest the 14-billion-year-old universe is in constant expansion. If that "inflation" model is correct, and it's based on solid findings, he said, the universe will "rip apart" billions of years from now.
The mysterious dark energy driving the expansion may produce strange effects, such as "the universe even could have not one end but rather 'multiends,' that is, some of its parts will come to an end at different moments," he said.
Father Funes' article was followed by a lengthier piece written by Piero Benvenuti, an Italian astronomer and the former head European scientist for the Hubble Space Telescope project.
He said the sciences, not soothsayers, have "very precise data on the evolution of the cosmos, particularly until what point a planet like Earth can sustain biological and intelligent life."
The world's end is linked to the evolution of the sun, which was formed about 5 billion years ago and will warm the Earth for another 3.5 billion years, he said.
As the gas fueling the sun starts to be depleted, the sun will slowly turn into a so-called "red giant," expanding more than 250 times its present diameter, he said. That means the planets closest to the sun, perhaps including the Earth, will be "swallowed up" by the swelling star, he said.
Not even setting up a human colony on another planet will save the day -- though it might delay the species' extinction -- because the sun's next dying phase as a hot, dense "white dwarf" will make the whole solar system uninhabitable, Benvenuti said.
More immediate world-ending disasters could be so-called "Near Earth Objects" -- chunks of ice or rock, some more than a mile wide -- hurtling close to Earth's orbit, he said.
Despite the inevitable end of the world, both Benvenuti and Father Funes underlined the hopeful message of Christ.
"It would be a good opportunity, during the season of Advent, that an alternative message of reassuring wisdom come from the churches' pulpits" to counteract the "improbable predictions and other militant prophesies" that have been flooding the media, Benvenuti said.
As the Gospel says, "the kingdom of God is at hand," and Jesus offers humanity "the opportunity to become immune to every upheaval, to every killer asteroid or gobbling sun, by seizing his saving word that doesn't change," he said.
Father Funes said human history has meaning as the world "was a gift of the God-with-us."
"The Word of God reminds us that we are heading toward a fundamentally good future, despite the crises of every kind in which we are immersed. That's because we are assured that, in Christ, there is a future for humanity and for the universe," he said.