John M. Grunsfeld Quotes

Discovering traces of life on Mars would be of tremendous scientific significance: The first time that any signs of extraterrestrial life had ever been detected. Many people would also find it heartening to learn that we're not entirely alone in this vast, cold cosmos.

As far as I'm concerned, Enceladus has become the go-to place in our solar system for issues bearing on extraterrestrial life. It's a great place to examine extraterrestrial organic chemistry that is water-based and, therefore, like biotic chemistry on Earth.

Theoretically, there are planets with an environment that can support life. As yet there is no evidence that there indeed is life on other planets. It's only a matter of time before we get to know.

It may be that no life is found, Which only to one engine bound Falls off, but cycles always round.

I actually think the chances that we'll find E.T. are pretty good.

Life outside of Earth is probably going to be really hard to find.

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.

Where there's water on Earth, you find life as we know it. So if you find water somewhere else, it becomes a remarkable draw to look closer to see if life of any kind is there, even if it's bacterial, which would be extraordinary for the field of biology.

The total number of people that do a job that has the same description as mine in the entire world is fewer than 10. There's a lot of effort looking for life in space - that's a lot of what NASA does, but they're not necessarily looking for the kind of life that can hold up its side of a conversation.

Maybe the search for life shouldn't restrict attention to planets like Earth. Science fiction writers have other ideas: balloon-like creatures floating in the dense atmospheres of planets such as Jupiter, swarms of intelligent insects, nano-scale robots and more.

We can never prove that we're alone in the universe. But the Allen Telescope Array could prove that we're not.

Wonder if there is life on another planet? Let's suppose there is. Suppose further, that only one star in a trillion has a planet that could support life. If that were the case, then there would be at least 100 million planets that harbored life.

With 'Extinction Machine,' I wanted to start some conversations about whether we're alone in the universe and what that might mean.

I think there must be some other life forms, even if they're microscopic.

We're going to understand that there is life on other bodies in the solar system.

If you set out in a spaceship to find the one planet in the galaxy that has life, the odds against your finding it would be so great that the task would be indistinguishable, in practice, from impossible.

I don't think we are the only planet that has life.

When I was a grad student at MIT, I had a chance to become friends with the Viking Mission's chief scientist, Dr. Gerald Soffen. Viking was the first Mars lander looking for signs of life on Mars.

I think there's all kinds of life out there, including intelligent life, but the reason we haven't found each other is because of vast distances.

It's presumptuous for us to think we are the only beings in the cosmos.

Among the plausible niches for extraterrestrial life in our solar system, the clouds of Venus are among the most accessible and the least well explained.

As far as whether there is life there on Mars or whether there was actually ever life there, I don't know. It would be great to find out, though.

There's no doubt that the search for planets is motivated by the search for life. Humans are interested in whether or not life evolves on other planets. We'd especially like to find communicating, technological life, and we look around our own solar system, and we see that of all the planets, there's only one that's inhabited.

Our field is very focused on finding Earth 2.0, and anything we can do to narrow the search is helpful.

The biggest breakthrough in the next 50 years will be the discovery of extraterrestrial life. We have been searching for it for 50 years and found nothing. That proves life is rarer than we hoped, but does not prove that the universe is lifeless. We are only now developing the tools to make our searches efficient and far-reaching, as optical and radio detection and data processing move forward.