Mark your calendars. October 21 is the end of the world, at least that is according to U.S. Christian broadcaster Harold Camping.

Should we start to bunker down and settle our affairs before Friday? Considering the Camping previously predicted the end of the world on May 21 and the world is still alive and kicking, we should look forward to surviving Friday and enjoy the rest of the weekend.

Never let it be said that Harold Camping is a quitter as he's back with more predictions of the world's end. But apparently the May 21 non-Apocalypse left the broadcaster flummoxed and he's now predicting a more benign end on October 21.

"The end is going to come very, very quietly probably within the next month...by October 21st," said Camping in a radio address delivered earlier this month.

"Probably there will be no pain suffered by anyone because of their rebellion against God...We can become more and more sure that they'll quietly die and that will be the end of their story."

Notice the word "probably"? Camping is now covering his bases in case the world goes right along existing this Friday. Not that Camping and his Family Radio won't be able to explain the world not going kaput on October 21. Back in May when Doomsday didn't occur, he simply reversed his position and said the Rapture will take a little longer than what God told him it would take.

"What really happened this past May 21st?" Camping said on his Family Radio website.

"What really happened is that God accomplished exactly what He wanted to happen. That was to warn the whole world that on May 21 God's salvation program would be finished on that day."

Camping's prediction back in May got a lot of media attention because of his organization's promotional campaign. He and his followers had thousands of billboards across the U.S. about the May 21 Doomsday scenario. Camping, an engineer by training, had calculated the end of the world from clues he found in the bible.

Even if October 21 proves not to be a Doomsday event, don't expect Harold Camping to give up his predicting duties. Not only does predicting the end of the world get him media attention, it's also a lucrative business to be in. Camping's supporters donated money to his non-profit company to promote the end of the world and since that didn't happen, Camping hasn't given the money back.