WHY NASA IS SENDING HUMAN MISSION TO THE MARS???

In the past few years many countries around the world had send the mission to the mars to explore it and find possibilities of life on mars.. 

Over the years, Nasa has sent five robotic vehicles,, known as rovers.. which are spirit, curiosity, opportunity, perseverance and sojourmer. As february 2021,  curiosity is still active while spirit, sojourmer and opportunity completed their missions before losing contact. 

Since these rovers has given many information regarding composition of atmosphere, composition of soil, rocks, and about the conditions of life on mars.. which are helpful for the scientists to study about the mars. 

Since these robotic vehicles has advanced technology in it,, but also they have many limitations. So, now american space agency is preparing for the human missions on mars. They will send humans to the mars for the better understanding of the conditions of mars in every aspects. 

Mars is one of the planet in our solar system which have almost same composition as earth..So from many previous years scientists are looking forward to explore the mars and to know everything about mars. They are looking forward to build a human civilization on mars..

But before building human civilization on mars,, it should be explore completely. Rovers has given the proof of life on mars,, In many pic taken by rovers something strange is seen. Which seems to be like the things on earth,, By looking this scientists are predicting that although mars atmosphere is unsafe for life,, but thousands years ago,, mars may have the conditions exactly same as on earth today..this seems to be that some civilization may exist thousands years ago on mars, but due to some reason that civilization extinct from mars..

If this is true than human missions on mars will reveal the secret of mars,, which is hidden beneath the surface of mars..