In Louise's report she debates whether it's a good idea to find out more about this planet or if it's just a waste of money.

Is it necessary to spend so much money sending robots to Mars?

Here are a few points on both sides.

Learn about Earth

On one hand Mars is the most Earth-like planet known to humans.

By finding out if there was life on Mars and if so what happened to it, we could find out more about what will happen to the Earth in the future.

No life?

On the other hand there might not have been life on Mars at all and therefore we would be spending a lot of money on nothing.

However, if they find life (which is possible because they recently found ice on Mars) we could possibly live there.