Quotes from David Grinspoon

The mature Anthropocene begins when we acquire the ability to live sustainably and become a lasting presence on this world.

There was a long history of people believing there was life on Venus. It was about the same size as Earth. It had clouds. It was commonly believed it was tropical - wet, hot and steamy.

What if life is not carbon-based? Can life exist as a gas or a plasma? Could planets or stars in some sense be alive? What about an interstellar cloud? Could life exist on such a small or large scale, or move so fast or so slowly that we wouldn't recognize it? Could you have an intelligent virus?

Whenever I see a nighttime picture of Earth from space, with its glowing lights, I am stirred by its beauty.

NASA, and all the other spacefaring nations of the world, have agreed to a set of 'planetary-protection' principles, aimed at preventing the accidental contamination of another habitable world with organisms from Earth.

You cannot study other planets without referring to Earth and without applying the techniques and the insights of Earth science. And you cannot really do a good job understanding the Earth without the insights from planetary exploration.

What we should really be thinking about is what it would look like for a truly intelligent technological species to be interacting with their planet's atmosphere.

Responsible global behaviour is ultimately an act of self-preservation of, by, and for the global beast that modern technological humanity has become.

We've almost been wiped out as a species many times, going back millions of years, and we've survived by reinventing ourselves and enlarging our circles of awareness, inventing new technologies and social structures.

I think a lot of people interested in space exploration tend to hear stories about the great missions, how they work technically, what we learned. But they don't really hear the story of what it takes to get a mission from scratch to the launch pad and into space.

Astrobiology is a great point of contact for science outreach. The public is naturally interested in extra-terrestrial life. Astrobiology provides an accessible point of access that leads to deeper questions.

My high-school friends and I felt part of a community of smart, forward-looking space and technology freaks.

There's eco-pragmatism, where you recognize, 'Yeah, we live on a planet that's permanently altered by humanity, and rather than seek to return to or preserve pure wilderness, we recognize that's an illusion, and we proceed under the new knowledge that we live, in fact, in a human-dominated planet.'

Radiation is one of the important factors in evolution. It causes mutation, and some level of mutation is actually good for evolution.

Mars does not have an atmosphere and does not have a magnetic field today, so the planet doesn't have the protection from radiation that our atmosphere and magnetic fields provide us on Earth.

We need to have a vision of the world we want to create so that we can see ourselves as collaborators with future generations in the project of shaping it.

What I'm interested in is the conversations going on about the Anthropocene and what it means to view ourselves as a part of Earth's geological history.

The basic ability to not wipe oneself out, to endure, to use your technological interaction with the world in such a way that has the possibility of the likelihood of lasting and not being temporary - that seems like a pretty good definition of intelligence.

Even as our unwitting alterations to Earth's carbon and hydrological cycles slowly make storms more damaging, our ability to monitor our planet from space and make reliable short-term forecasts have equipped us enormously to withstand them.

In my Ph.D. thesis, written in 1989, I discussed the fact that when a civilization develops the technology to prevent catastrophic asteroid impacts, it marks a significant moment in the evolution of the planet.

Even as a kid enthralled with science fiction, I wondered about the role of people in the long-term evolution of the Earth, the far future and the fate of humanity.

Earth is a stunningly lovely planet for so many reasons. Among these is the wondrous presence of curious, artful, inventive humanity.

Now, humans have become a dominant force of planetary change and, thus, we may have entered an eon of post-biological evolution in which cognitive systems have gained a powerful influence on the planet.

Time and time again, our species has escaped existential threats by reinventing ourselves, finding new skills not coded in our genes to survive new challenges not previously encountered.