Tag Archives: Science

Astrophysicist Andrew Skemer Brings Distant Planets Close to Home

By Chloe Lindeman, Co-Editor-in-Chief

The question of whether life exists on other planets is one of the most fundamental questions humans ask. It is also one of the most difficult to answer.

This week, Swarthmore College alumnus and Astrophysicist at the University of California Santa Cruz Andrew Skemer came to Haverford’s campus for a talk and informal lunch, both revolving around his research on exoplanets, or planets that orbit stars other than our sun. The first was found in 1995; as of now, more than 3000 have been detected.

“When I started grad school, there was like one exoplanet paper a week, and now there are like 10 a day,” said Skemer. “It’s a really exciting 10 to 20 years coming up in exoplanet imaging.”

Skemer’s work relies on something called adaptive optics, which take earth’s atmosphere into account to improve images coming from telescopes. In addition to teaching us about our own solar system, studying exoplanets lets us answer questions about the wider universe, including how common these orbiting bodies are.

“Planets around stars are ubiquitous. They’re everywhere,” said Skemer. This includes our nearest neighbors – earlier this year, neighboring star Proxima Centauri was found to have a planet orbiting it in its so-called ‘habitable zone.’ Exoplanet imaging and other detection methods promise to give us more information.

“In the next 20 years, we’ll have a spectrum of [Proxima b] and we’ll know if there’s oxygen and methane on it,” said Skemer, noting two atmospheric gases whose presence may be one indicator of life.

Arjun Khandelwal (HC ’17), a physics and astronomy double major who does exoplanet research of his own, highlighted the importance of Skemer’s work and studying exoplanets in general.

“[Exoplanets] help us answer one of the grandest questions in the world: whether we are alone in the great enveloping cosmic dark,” said Khandelwal. “Most exoplanet work focuses on finding them in indirect ways because imaging them is really hard, but adaptive optics … is a wonderful technique to actually get pictures of alien worlds. It’s amazing that we have the ability to do that!”

Alien life or no, exoplanets promise to be important in the future of astronomy. Skemer pointed out that, when it comes to some areas of astronomy, like stars, we have answered most of the basic questions. We can observe a star and determine things like its mass, age and composition.

“With exoplanets, I promise you, we’ve answered almost none of the questions.” And that, Skemer says, is exactly what makes this such an exciting field.

For now, we can’t say much about the possibility of life on even the planets around the closest stars, but stay tuned.

“The next two or three decades will be the first time in human history that we’ll be able to detect life on other planets, if there is any,” said Khandelwal. “I was always fascinated by that question growing up, and it’s absolutely incredible to me that it might be answered in just the next couple of decades.”