IS THE MONEY USED FOR SPACE EXPLORATION A COMPLETE WASTE ??

I've heard a bunch of people complaining about the excessive use of money for space exploration. We have many problems on the earth itself but instead of solving those why in the world do we launch rockets and waste tons of money. I've even heard people say that space exploration is a luxury that is completely unnecessary. Well, do you think the same?

The thing is that humanity is very insecure. Just like the asteroid that obliterated the planet billions of years ago, there are many more lurking around the corner. And in a matter of seconds, humanity may vanish into thin air. Hence, to find an alternative place to live in case of emergency or colonizing the space so that even if one planet is destroyed, humanity as a whole can survive, space explorations turn out to be a compulsion. The money may not be directly beneficial to us but it can be considered as an investment for our future generation and the entire human race. 

There are many more points, aspects, and layers to this that won't fit in this short article. So, do comment if u want a detailed version of this. It will encourage me and help me push myself further.