Details on the orbits of 450 possible exoplanet targets from the European Space Agency’s Ariel space mission were presented this week at the Europlanet Science Congress (EPSC) 2022 and submitted for publication in the Astrophysical Journal Supplement Series. The study, coordinated by the ExoClock project (www.exoclock.space), was co-authored by 217 professional and amateur astronomers, as well as university and high school students.
“The ExoClock ethos can be summed up in three keywords: inclusive, interactive and integrated. It is open to all and accepts contributions from amateur astronomers, students, schools and citizens,” said Anastasia Kokori, ExoClock project coordinator. “This is the ExoClock team’s third release. The majority of the authors are amateur observers – approximately 160 – and this significant number underscores the interest and value of the amateur community in contributing to space exploration.”
Ariel will study a population of more than 1000 exoplanets to characterize their atmospheres. Launched in September 2019, the ExoClock project aims to support the long-term monitoring of exoplanets through regular observations with small and medium-sized telescopes.
Participants submit measurements, known as “light curves,” showing the drop in intensity as a planet “transits,” or passes in front of its host star and blocks some of the light. When Ariel launches in 2029, it will need accurate knowledge of the expected transit time of each exoplanet it observes to maximize mission efficiency and impact.
“The new study showed that over 40% of the ephemeris for proposed Ariel targets needed to be updated. This underscores the important role the ExoClock community can play in regularly monitoring the Ariel goals,” said Tsiaras.
ExoClock participants plan and conduct observations, analyze the data, and submit their results for review and feedback by members of the science team. This interactive process helps ensure consistency of results and enriches the experience of participants learning through dialogue.
The results show that small and medium-sized telescopes can successfully observe ephemeris for the vast majority of candidate Ariel targets. They also show how observations made by amateur astronomers with their own telescopes can contribute to real science and have a major impact on a mission. The project is helping to integrate Ariel with other space missions, ground-based telescopes, literature data and the wider society while making the best use of all available resources.
Kokori said: “Science is for everyone and we are very excited that through the project everyone can be part of a real space mission. Our observers come from more than 35 countries and have different backgrounds. It’s wonderful to see so many people willing to learn and work together in a collaborative spirit. Our team is growing every day with participants from all over the world.”