Professor Joe Carson likes to joke with his astrophysics class: Find a planet, you get an “A.” No planet, “F.”

Finding a planet

Two College of Charleston seniors have discovered a planet in the Andromeda galaxy. Here are a few facts about it:Name: k And b (for kappa Andromedae, the star, and the “b” planet discovered in the Andromeda galaxy).Distance from Earth: 170 light years.Size: 1.8 times bigger than Neptune, more than 100 times bigger than Earth.College of Charleston, Joe Carson

Seniors Thea Kozakis and Laura Stevens just scored the “A.” Analyzing photographic data from the Subaru telescope in Hawaii, Kozakis noticed a giant light shining closer in to the massive star kappa Andromedae than she had ever seen before.

After months of monitoring and data crunching, she and Stevens confirmed that when the star moved, the light moved with it. The body wasn’t a star in the sky background; it was orbiting the star.

How cool is that? Among nearly 850 planets discovered outside the solar system, only a handful have been located directly from telescope images. The idea that two undergraduate students accomplished the rare feat is “even more unusual, if not unprecedented,” Carson said.

And significant science. Researchers have questioned whether massive stars have any planets in orbit, and speculated that if they do, the planets themselves would be large. K And b, the planet the students found, provides some answers.

The College of Charleston team among others now will study its orbit, atmosphere and gravity, looking for more clues about its makeup and whether any orbit irregularities suggest another planet around it.

The discovery was so ground-breaking that it had to be kept quiet until the data could be verified. They gave the planet the random nickname “Derek,” at the astronomy lab manager’s suggestion, so they could talk about it. The name stuck. Derek is what they call the planet today.

Derek is a gaseous blob that is a lot like a huge Jupiter, itself the largest planet in our solar system. So no, there’s no life there. But if Derek has moons, they “would be excellent places to find life,” Carson said.

For Kozakis, who grew up peering at planets with her amateur astronomer father, John Kozakis, this is life-dream stuff. A physics and astrophysics double major, she wanted to study the cosmos because there was so much left to discover. It’s a little mind boggling to make one of those discoveries so early in her career.

“I can’t really believe it, just knowing I was the first person in the world to see this planet,” she said.

Her dad told her he always expected she would do things like this. Her mom, Jackie Kozakis, “has already told half the world,” she said.

Well, professor, does she get the grade?

“They’ll all get A’s on this project,” Carson said, laughing. “If I could give them a higher grade I would.”

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