Ohio State astronomers win ExoCup 2018

Adreyn Yates
Wed, 12 Dec 2018 02:16:30 +0000
Campus, News, astronomy, ExoCup, exoplanet, ohio state, Ohio State astronomy, Ohio State astronomy research, Ohio State exocup, Ohio State exoplanet research

The ExoCup winner, KELT-9b, orbiting around its star, KELT-9.
Credit: R. HURT/IPAC/JPL-CALTECH/NASA.

A planet discovered by a team co-led by Ohio State astronomers won an international, intergalactic competition known as the ExoCup.

Scott Gaudi, professor of astronomy at Ohio State, is co-principal investigator of the study, Kilodegree Extremely Little Telescope or KELT, that discovered the winning planet, KELT-9b, along with astronomers Keivan Stassun from Vanderbilt and Josh Pepper from Lehigh University.

The ExoCup is a NCAA March Madness-style competition. Astronomers submit their exoplanet discoveries to Exocast, an exoplanet podcast hosted by three scientists, and they choose which planets face-off against each other on Twitter where participants have 24 hours to vote for the best exoplanet, planets outside our solar system. The exoplanet that won its bracket moves on to the next, totaling four rounds.

After winning the first round, Gaudi said he started asking his students and the astronomy department to head to the Twitter polls to vote for KELT-9b, so it could make it to the second round.

“We won the second round pretty easily, and then, it went to the third round. That [round] was a lot closer, and we barely got by,” Gaudi said.

Securing a third round victory, KELT-9b headed to finals.

In the finals, KELT-9b went head-to-head with a young planet, PDS 70b, which was “born” earlier this year. This planet was discovered with the high-tech, 8 meter Gemini telescope in Chile. Gaudi said he knew this round would be a tough one, so he “pulled out all the stops.”

Gaudi said he had an extra 24 hours in the finals to get votes for KELT-9b, so he turned to twitter, colleagues and his students to submit their vote before time ran out.

“At that very last 10 minutes, we went from 49% of the votes to having 51% of the votes. We just barely squeaked by right at the very end,” Gaudi said.

“It’s just for fun,” he said. “It’s a really great way to get people involved with exoplanets and to learn about them.”

KELT- 9b was discovered by KELT, a camera lens-like telescope. After a lot of research and hard work, Gaudi and his team declared their discovery a real planet and were able to report in the June 2017 issue of Nature and at a presentation at the American Astronomical Society’s spring meeting.

The gas giant is about twice the size of Jupiter and almost as hot as our solar system’s sun. The planet orbits its parent star, KELT-9 — which is twice the size and temperature as our sun — in about 1.5 days. This planet and its parent star are located in a constellation called Cygnes, which is about 650 light years from Earth, according to Gaudi.

“It’s very, very close to its parent star and because the planet’s parent star is so hot it’s bombarding this planet with high-energy radiation,” Gaudi said. “That makes the planet very hot, so the planet itself is actually almost as hot as the sun and hotter than most stars we know of — based on day side temperature.”

Gaudi said KELT-9 is a strange planet, and that the group knows hydrogen is escaping through evaporation due to the heat. He added that the planet is so hot, the entire planet is made of gas and that no solids can form.

Gaudi added that it is exciting that such a small telescope can discover these planets given what he says is a popular assumption that a larger telescope is needed.

“I think this highlights the kind of things that are happening here that probably a lot of students aren’t aware of,” Gaudi said.

The winners of ExoCup 2018 are automatically in ExoCup 2019. Gaudi said he hopes to see students participate in next year’s competition and KELT-9b will be the winner of another cup.