April 30, 2024

Life on Earth and Beyond

“I always said the most interesting thing about me are my socks.” – Thomas Zurbuchen

In the wake of the recent ETH Global Lecture: Life on Earth and Beyond, I found myself thinking about the existence of extra-terrestrial life in the universe and the importance of planet socks. It turns out that both can be explained in simple terms. The first goes like this: With all the many, many billions of probable planets outside our solar system, the chances of there being – or that there has been – life on a number of them is high. The question is only: What kind of life?

Thomas Zurbuchen, Swiss-American astrophysicist, ETH Department of Earth Sciences, previously the head of NASA’s science missions, is initially on hand to shed light on the planet socks issue. Newly hired in 2016 as the associate administrator for the science directorate at NASA after an academic career, he found himself in need of clothes that would suit appearances before the US Congress. Wanting to add an interesting accent to his conservative new attire, Zurbuchen knew the right opening: socks that matched his job. Socks with planets on them. Socks he shows off at the lecture.

Also in attendance is the Swiss astronomer and Nobel Prize winner Didier Queloz. Also wearing planet socks. “I knew I would be sitting next to you.” He grins over at Zurbuchen. It’s a great start to a relaxed existential discussion.

Both scientists are now part of ETH’s research on exoplanets and space, which also entails looking at why there is life in the universe and whether we are alone.

The answer to which, since the first exoplanets were discovered in 1992 (by Queloz and two colleagues) turns out to be probably not. The list of newly located planets has increased exponentially from hundreds to thousands — 5616 as of last week according to the Nasa Exoplanet Archive.

Let’s assume you are looking at a projected image of the first image released from NASA’s James Webb Space Telescope ((Part of host Anna Maltsev’s presentation), which shows thousands of galaxies. According to Zurbuchen, if you were to put a grain of sand on the tip of your finger and stretch it out towards the image, you could cover 6000 galaxies behind that little grain of sand. If you extrapolate, he says, “that makes an order 100 billion stars, perhaps up to 400 billion. With thousands of billions of worlds that are there, and every one of those stars on the average has one planet or more.”

Queloz links possible life on those planets to physics: “There’s a magical element in our galaxies because the laws of physics are such that they enable the stars, they enable the chemistry, they enable water, they enable planets and they enable life. They even enable the consciousness we’re using for this discussion.”

“That’s why I’m a strong believer that we will find out why there is life. There’s the beautiful element of the power of the brain, it’s a fascinating tool. It’s the most powerful tool we can use think in this universe right now.”

“So the universe makes a brain that thinks about itself,” Zurbuchen quips.