Finding a planet

How a student-led team put Aarhus on the astrophysics map

by Joe Sutherland and Sofia Gerganova

Kepler 62f, one of two habitable planets found recently (NASA AMES)

Kepler 62f, one of two habitable planets found recently (NASA AMES)

It’s not every day you discover a new planet. So when Aarhus University PhD candidate Vincent van Eylen did so last month, it raised more than a few eyebrows.

Van Eylen, who is 24, led a team to the discovery of Kepler-410A b, a planet orbiting a sun some 425 light years away. It was even more impressive since it was made entirely by a team at Aarhus University. It is the first time one of their PhD candidates has led an effort to document a new planet.

“This is the first time that someone from this university has led the work to confirm the existence of a planet, as opposed to being a part of a [larger] team,” says Jørgen Christensen-Dalsgaard, the head of the astrophysics department at Aarhus University. “For a PhD student, it’s very important to discover something as big as this.”

The planet has been under observation for around four years. It is one of several found near Kepler-410 A, a star found and observed with NASA’s Kepler satellite. It is similar in makeup to Neptune, and is almost three Earths wide. It is much closer to its sun than we are: a year on Kepler-410A b would take only a few weeks, so the planet is likely to be far too hot to sustain life.

Van Eylen’s team consisted of fifteen researchers and astrophysicists from seven different universities. All pooled their various talents into Aarhus for this venture. The process up to this announcement hasn’t been straight-forward.

“There wasn’t really one moment when we realised everything was correct,” Van Eylen says. “It was rather a process of gradual improvements which has ultimately led to the paper. Having that accepted for publication after a process of peer-review was, of course, a great moment.”

A moment that was quite straight-forward was a high-profile endorsement from his home country. On January 22, the Prime Minister of Belgium, Elio Di Rupo, used the hashtag “#BelgianTalent” on Twitter to cap off his praise.

“Congratulations to the Belgian Vincent Van Eylen, who has discovered a new extrasolar planet with his team!” he wrote.

A Belgian in Aarhus

Vincent Van Eylen first arrived in Denmark on an Erasmus-supported masters programme. He hails from Keerbergen, a small town near the centre of Belgium sporting just under 13,000 residents at last count.

Astronomy is a subject curiosity led him into. “For a long time I didn’t quite know what I would go study,” he says. “I started doing astronomy out of interest, after choosing physics earlier, but it is not that I have wanted to do this all my life.”

Van Eylen, from Belgium, led the Aarhusian team and was greeted by his home country prime minister (PHOTO: Vincent van Eylen)

Van Eylen led the Aarhusian team in the discovery and was greeted for it by his home country prime minister on Twitter (PHOTO: Vincent van Eylen)

For him, the possibility of life on other planets is a focal point of his future research, fuelled by a desire to know more about the universe.

“I think it is absolutely fascinating to wonder if there is life somewhere else in the universe,” he says. “It is one of those big open questions, which we haven’t conclusively answered.”

With a small population and chilly winters, Aarhus can seem an unusual choice for international students. Van Eylen says the successes of the university, particularly in scientific research, helped make his decision for him.

Kepler-410A b is just one of several large projects underway in Aarhus. In April of last year, the university announced its involvement in a 37 million kroner investment in the aptly-named European Extremely Large Telescope – an apparatus that will measure four times the diameter of the current largest in the world.

The telescope will be strong enough to see signs of life on other planets “at a light years distance”, according to astrophysicist Uffe Gråe Jørgensen of the University of Copenhagen. “The good image quality will mean that you can see individual stars in distant galaxies,” he continues, “some 60 million light years from here.”

Yet, Aarhus University’s exploration of new facilities doesn’t stop there. Currently, the university is building two more telescopes, in Tenerife and China. This will form part of the Stellar Observations Network Group (SONG) initiative, seeking to create an international network of robotic telescopes.

“When a star sets here, it will be rising in the US, when it sets in the US, it will be rising in China. Then we could continue to keep a watch of the star,” professor Christensen-Dalsgaard says.

SONG aims to make it easier for researchers to age and identify new stars light years away. The network will also seek out new planets with similar characteristics to Earth, in hopes of finding signs of life elsewhere in the universe.

The end goal for SONG is to create eight identical “nodes”, four in each hemisphere. This will allow the observation of the same stars for months at a time.

“The Brits once said that the sun never sets in the British Empire,” Christensen-Dalsgaard adds. “What we say is that a star should never set at Aarhus University.”

Van Eylen will also be involved in other planetary work at the university over his doctorate, which lasts a further two years. “I am sure that in exoplanets, there will be many great results to come in the next few months and years from our university and of course from astronomers worldwide,” he says. “The best discoveries are the next ones.”

Joe Sutherland and Sofia Gerganova are undergraduate students from the UK currently living and studying journalism in Denmark.