I have always been interested in the topic of life beyond Earth.  Do you believe in the possibility of alien life?
I'm not sure. The science of studying extraterrestrial life in all the different forms is called exobiology.
The fact that scientist have found evidence that planets such as Venus and Mars could have been hospititible enivronments leads me to think that alien life is a possibility
Even though  mars had oceans in the past, now it's cold, dry and pretty much uninhabitable. 
Yes, but since it was habitable possibly in the past, think about what other planets out in the universe might be habitable for life.  
Yes cumulative evidence shows that during the Noachian time period, Mars's surface had liquid water and could have possible been inhabitable for microorganisms.
There have been a lot of studies about possible future colonization of Mars.  I find that to be really cool
There is something called the Drake Equation. It speculates the possible existence of life somewhere else in the universe.
I have heard of that.  It is a formula to estimate the existence of extraterrestrial life
They have actually been searcing for extraterrestrial life since the mid-20th century.