There are a number of "beliefs" if you will. If you want to believe the stories in the bible you have to accept that a civilization long before the bible's existence believed something totally different well almost anyway. Much of the bible and other religious scriptures resemble what the Sumerians believed. From what Zacharia Sitchen and others have translated from the Sumerian tablets is that the Sumerians were genetically created by "Anunnaki." Anunnaki were supposedly from planet Nibiru. The story is the Anunnaki genetically created the Sumerian people with a mixture of DNA of Ape and Anunnaki as slave to mine gold and other minerals. The first of those being Adam and Eve although their names were different this is what they were translated to be at the time of the writing of the bible.
As far as mars is concerned it is believed that it's a rest stop if you will for the Anunnaki when they visit earth.
Now as far as the "Great flood" is concerned. There are several explanations to that. One of those being that when Nibiru aka Planet X came into our solar system on it's 3600 year orbit it struck Earth (known as Tiamet) creating our asteroid belt, the moon, etc. The stars are believed to be fragments of Nibiru which is known to be a glowing planet. There's a lot more to this story but more or less it's why Earth is so different than other planets. The large gashes in it's surface (Oceans) and it's believed that all continents were in fact one. But after the collision the continents began to drift apart (continental drift or plate tectonics) and this is why there was life on all continents. IE the Indians in North America, etc
The other is that the Anunnaki Gods and half brothers Enki and Enlil fought over whether or not to kill all humans. Enki and his half sister Ninki created Adam and Eve. While Enlil created Edin. Enki was the serpent who encouraged them to eat from the tree of knowledge. Enlil drove them out of the garden and Enki was there to clothe them. During the time of Noah Enlil wanted to wipe out all of mankind because he thought they were rebelling. So he created the Great Flood while Enki gave Noah the plans to build the Ark.
It's a pretty interesting story I do have to say. And if you really do the studying of it it gets into explaining the Pyramids which is where the Sumarians began, stone henge, Easter Island, Nasca Lines, etc . Another interesting bit to note here is Sumar was where Iraq is now. Some other interesting things to point out is the whole deal with 2012 is because the Sumerians. Myans, Indians etc all pretty much had a similar calendar. The calendar itself is more or less ancient astrology. The reason it ends in 2012 12/21/2012 to be precise as far as the Sumerians are concerned is because this is suppose to be when Nibiru enters back in to our orbit.
And others believe that Pluto has a lot to do with it as well. The masks are coming off.
