10 POINTS!! What are some good points to why space exploration is worth the cost?

Earth is not going to sustain life forever. Eventually an event will happen that could very well destroy the planet (such as a large comet striking the planet, the sun dying out, a singularity event or we could tear the world apart ourselves through war or experimentation with forces we cant control). This could happen tomorrow or a billion years from now. If the Human race wants to survive as a whole, we need to branch our existence out through the cosmos. Not to mention the chance for scientific discovery that could revolutionize technology as a whole, or make energy cleaner, cheaper and more efficient. But, just like digging an oil well, it will be a gamble. There is no sure evidence that any other known planet (even those outside our own galaxy) can support human life, or that we will discover any new elements or materials that will be of any benefit to us. It is a gamble we must endeavor to make though. I hope this was helpful