As we approach the 100th anniversary of the Titanic sinking on April 15th - and the 3D re-release of the movie Titanic on April 4th - we thought we'd share some things you probably didn't know about the Titanic. For instance: -A full moon may have caused the fatal iceberg to cross paths with the Titanic. That's according to Donald Olson, an astronomer at Texas State University-San Marcos. He quotes National Geographic's Richard A. Lovett, saying a full moon in January of 1912 may have caused strong tides that sent a bunch of icebergs southward into the Titanic's path.

-Nearly 5 Titanics could be built with the money James Cameron's Titanic movie has made worldwide. The California ScienCenter says the Titanic would cost about $400 million to build today. The movie Titanic has made over $1.8 billion worldwide since it's release in 1997. The money earned from the April 4th 3D re-release will only add to that total.

-You can take a cruise that echoes the Titanic experience. They will leave exactly 100 years after the Titanic began it's voyage. They'll go to Halifax, Nova Scotia, where many of the Titanic victims were laid to rest. Later they will go to the spot in the Atlantic where the ship sank for a day of reflection. They offer no guarantees that you'll spot an iceberg on this memorial cruise.

Check out the trailer of the 3D re-release of Titanic, and take our Titanic quiz and see if you can guess which answer is false.