Space exploration is like those people who explores earth after the extinction of dinasours. There are too much thing to explore. And mankind should know earth is small planet among trillions. So, there are more living things in other place. Alien is the proof that there are other living things which are more high tech than us. Perhaps they call us 'alien' too? Space exploration is really important to find an alternative planet or resources. Human should accept the fact that other 'living thing' is exist in this universe.

Earth definitely is dying. No one can save our earth, but reducing the effects of global warming, ozone layer depletion are possible. But again, we cannot create ozone layer or create iceberg at northpole.

Space got more mysteries than our earth. That is why we need to explore.