Five centuries ago, the Italian mathematician and philosopher Giordano Bruno was burnt alive by the Catholic Church for asserting that our universe may have innumerable suns and infinite earths that revolve around it. Today, we know of more than 3,500 planets orbiting various stars in the Milky Way, all discovered within the last quarter of a century. Humankind could move away from the medieval dark ages largely by virtue of the unrelenting nudge that science gave to our collective wisdom and conscience time after time.
The plethora of planets discovered beyond the confines of our solar system has reopened, with a whole new vigour, the question of ‘are we alone in this universe’? Henry Throop is someone who has been a frontline participant in the ongoing quest to understand habitable worlds outside of Earth.
As a scientist with the Planetary Science Institute in the US, Henry investigates the big questions in planetary science, including the origin of life on Earth, and the likelihood of it happening elsewhere in the universe.
About 20 years ago, the first discovery of planets around Sun-like stars was made. This was a vital moment in history as, Henry explains, “for the first time, we had evidence that our solar system was not the only place that had planets. In a sense, this was similar to the big shift that happened in our thinking when we realised that the Sun, and not the Earth, was at the centre of the solar system. Suddenly, we were not the centre of the universe — but inhabitants of one of many planets in the solar system.”
Seen against the backdrop of desolate space, Earth may appear a tiny world. Yet, our planet is much interesting because it is the only place that we know of, that supports life in such endless forms, one of which has evolved to a level where it has begun to wonder about its own origins, and of the universe and the possibility of life elsewhere.
Ambitious adventures
“Humans are curious, which is what makes us explorers,” says Henry. “Understanding the universe isn’t something we do because of its utility, or because of any short-term economic benefit. We do it because that is what defines us.”
It’s this perennial urge to peep into the unknown that has led to ambitious adventures in space science. As a key member of the science team for NASA’s New Horizons mission, the spacecraft that rendezvoused with Pluto in 2015 after a journey of 10 years, Henry explains the thrill of studying alien worlds distant from us. “Pluto was the last unexplored planet in the solar system.
Just like explorers on Earth went on travel across the globe to find what was beyond their horizon, the same we are doing now with exploring the solar system. New Horizons’s flyby of Pluto showed that many of our guesses about the outer solar system were completely wrong! The biggest surprise was that Pluto is more geologically active than we thought it would be. Pluto is small, old, and far from the Sun — all things that should make it cold and ‘dead’ — but what we found was that it was more geologically active than we thought. Such discoveries also help us understand how planets of the solar system compare to the ones we are discovering elsewhere.”
Henry Throop’s interests as a planetary scientist cuts through different areas, from the origins of life on Earth, to the formation of the solar system, search for rings around Pluto, and the evolution and habitability of planets around other stars. “I’m very lucky to be in a field where we are studying things that the public is also deeply interested in. The questions that scientists ask about the universe are essentially the same ones that public also ask,” which is why Henry spends a major chunk of his time in outreach activities, interacting with the public.
Staggering diversity
While living in Africa for three years, he worked extensively with rural schools, helping to develop their science programs. He has travelled and presented hundreds of lectures in science festivals, planetariums, school groups and public events across the US, Mexico, Africa, and lately in India. “Science is only useful when knowledge is shared. The public after all funds our work,” he says.
Henry has made India his home for the past two-and-a-half years, teaching at the St. Xavier’s College in Mumbai, doing research and also interacting with school and university students. Having travelled the breadth of the country, he finds the staggering diversity of India most inspiring. “I find the people of India to be optimistic, hard-working, with strong goals and dreams. It’s great to be around so much energy and enthusiasm.”
Henry Throop was in the city earlier this week for a series of public lectures on planetary science and astrobiology at the Indian Institute of Space Science & Technology, and the Kerala Science & Technology Museum.
