Unfortunately, pioneers will always pave the way with sacrifices.

We can continue to try and clean up the gutters all over the world and spend all of our resources looking at just the dirty spots and trying to make them clean. Or we can lift our eyes up and look into the skies and move forward in an evolutionary way.

Kids, help your parents if they don't know how to use a smartphone.

The best way to study Mars is with two hands, eyes and ears of a geologist, first at a moon orbiting Mars... and then on the surface.

I know: If you're looking down at Earth, you're looking through an atmosphere that has a bit of haze in many places and not just occasional clouds.

The first human beings to land on Mars should not come back to Earth. They should be the beginning of a build-up of a colony/settlement, I call it a 'permanence'.

The energy varies with the square of the velocity, so if you need five times the velocity, that's 25 times the energy.