..>Is there any chance that we can put a man on Mars?>.........
>Is our sun unique, or is it just a type of star?
It does not seem to be terribly special. There are many other star systems with similar stellar characteristics as ours (probably several billion in our galaxy alone).
>Now within 100 years...
>Is there any chance that we can put a man on Mars?
>... put a man outside the Solar System?
>... find other Earth-like planets?
>... find life on other planets?
Yes, yes, yes and yes.
Man on Mars. It could be done within 20-50 years, if money and politics were not factors.
Man outside the solar system: No
Find Earthlike planet: Depends on what you define as Earthlike, but there have been hundreds of extrasolar planets detected, the problem with Earthlike ones is, they are smaller, and our detection methods are most reliable for finding very large (massive) planets like Jupiter massed or bigger.
Find life on other planets: Doubtful. Given the vastness of space, and the distances involved, life would have to be rather abundant in our spur of our spiral arm to have any chance of ever detecting it.
I think they've found one or two extrasolar planets that have the potential to be earth-like, meaning about the right size and temperature, but detecting things like water or an atmosphere on them is still beyond our means. As for landing on Mars, if NASA had twice the budget it does now, which is modest by the way, we could start sending people to Mars within a few years. Technologically, there are no hurtles in our way of doing that. I doubt any missions outside the solar system will be possible within the next 100 years, however. The distances are just too great. Our fastest probes would take thousands of years just to reach the nearest star.
Just to add to the first answer: I am pretty sure that Obama set a goal to put a man on Mars in the year 2020 or something like that.
