Press Releases

ExoClock Press Release (09/2022)ExoClock Counts Down Ariel Exoplanet Targets 

ExoClock Logo. Credit: ExoClock.

Details of the orbits of 450 candidate exoplanet targets of the European Space Agency’s Ariel space mission have been 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, has been co-authored by 217 professional and amateur astronomers, as well as university and high school students.

“The ethos of ExoClock can be described in three key words: inclusive, interactive, and integrated. It is open to everyone and accepts contributions from amateur astronomers, students, schools and public citizens,” said Anastasia Kokori, ExoClock project coordinator. “This is the third paper produced by the ExoClock team. The majority of the authors are amateur observers – around 160 – and this significant number highlights the interest and the value of the amateur community in contributing to space research.”

Ariel will study a population of more than 1000 exoplanets to characterise their atmospheres. The ExoClock project, which launched in September 2019, aims to support the long-term monitoring of exoplanets through regular observations using small and medium scale telescopes. 

Participants submit measurements known as ‘light curves’, which show 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 to have precise knowledge of the expected transit time of each exoplanet that it observes, in order to maximise the mission’s efficiency and impact.

“The new study showed that over 40% of ephemerides for proposed Ariel targets needed to be updated. This highlights the important role that the ExoClock community can play in monitoring the Ariel targets frequently,” said Tsiaras. 

ExoClock participants schedule and carry out observations, analyse the data and submit their results for review and feedback from members of the science team. This interactive process helps maintain consistency in results, and enriches the experience of the participants who learn through dialogue.

The results show that small and medium sized telescopes can successfully observe ephemerides for the large majority of the Ariel candidate targets. They also show how observations by amateur astronomers using their own telescopes can contribute to real science and have a high impact for a mission. The project helps to integrate Ariel with other space missions, ground-based telescopes, literature data and wider society, making best use of all available resources.

Kokori said: “Science is for everyone, and we are very happy 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 is wonderful to see so many people willing to learn and work together in a collaborative spirit. Our team keeps growing daily with participants from all over the world.” 

Further information

The project is part of the Ariel ephemerides working group, aiming to refine the ephemerides of Ariel targets. 

The updated ephemerides were produced as a result of a combination of around 18000 data points: 2911 observations from the ExoClock network, 12633 light curves from space telescopes, 2442 mid-time points from the literature and 184 observations provided by the Exoplanet Transit Database (ETD). 

The pre-print of the publication is available at:

The database is accessible at OSF:

Science Contacts

Anastasia Kokori
London, UK

Angelos Tsiaras 
Arcetri Astrophysical Observatory – INAF
Florence, Italy


EPSC2022 Press Office
+44 7756 034243


About the Europlanet Science Congress (EPSC) 

The Europlanet Science Congress ( formerly the European Planetary Science Congress, is the annual meeting of the Europlanet Society. With a track record of 16 years, and regularly attracting around 1000 participants, EPSC is the largest planetary science meeting in Europe. It covers the entire range of planetary sciences with an extensive mix of talks, workshops and poster sessions, as well as providing a unique space for networking and exchanges of experiences.

Follow on Twitter via @europlanetmedia and using the hashtag #EPSC2022.

Details of media briefings and recordings can be found at:

All Europlanet media releases can be found at:

About Europlanet

Since 2005, Europlanet ( has provided Europe’s planetary science community with a platform to exchange ideas and personnel, share research tools, data and facilities, define key science goals for the future, and engage stakeholders, policy makers and European citizens with planetary science.  In 2022, EPSC is held jointly with the European Astrobiology Network Association (EANA) annual meeting.

The Europlanet 2024 Research Infrastructure (RI) has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 871149 to provide access to state-of-the-art research facilities and a mechanism to coordinate Europe’s planetary science community. 

The Europlanet Society promotes the advancement of European planetary science and related fields for the benefit of the community and is open to individual and organisational members. The Europlanet Society is the parent organisation of the Europlanet Science Congress (EPSC).

About EANA
The European Astrobiology Network Association (, joins together people interested in the origins of life and the search for extraterrestrial life in the Solar System and beyond. This interdisciplinary domain involves scientists from multiple disciplines such as chemistry, physics, biology, geology, astronomy, and human sciences.  

Example of scientific data produced by amateur astronomers. Credit: ExoClock

Ariel Press Release (06/2022) – Calling AI experts! Join the hunt for exoplanets

Artificial Intelligence (AI) experts have been challenged to help a new space mission to investigate Earth’s place in the universe.

The Ariel Data Challenge 2022, which launches on 30th June, is inviting AI and machine learning experts from industry and academia to help astronomers understand planets outside our solar system, known as exoplanets.

Dr Ingo Waldmann, Associate Professor in Astrophysics, UCL (University College London) and Ariel Data Challenge lead said:

“AI has revolutionised many fields of science and industry in the past years. The field of exoplanets has fully arrived in the era of big-data and cutting edge AI is needed to break some of our biggest bottlenecks holding us back.” 

Understanding our place in the universe

For centuries, astronomers could only glimpse the planets in our solar system but in recent years, thanks to telescopes in space, they have discovered more than 5000 planets orbiting other stars in our galaxy.

The European Space Agency’s Ariel telescope will complete one of the largest ever surveys of these planets by observing the atmospheres of around one fifth of the known exoplanets.  

Due to the large number of planets in this survey, and the expected complexity the captured observations, Ariel mission scientists are calling for the help of the AI and machine learning community to help interpret the data.

Ariel Data Challenge

Ariel will study the light from each exoplanet’s host star after it has travelled through the planet’s atmosphere in what is known as a spectrum. The information from these spectra can help scientists investigate the chemical make-up of the planet’s atmosphere and discover more about these planets and how they formed.

Scientists involved in the Ariel mission need a new method to interpret these data. Advanced machine learning techniques could help them to understand the impact of different atmospheric phenomena on the observed spectrum.

The Ariel Data Challenge calls on the AI community to investigate solutions. The competition is open from 30th June to early October.

Participants are free to use any model, algorithm, data pre-processing technique or other tools to provide a solution. They may submit as many solutions as they like and collaborations between teams are welcomed.

For the first time, this year the competition is also offering 20 participants access to High Powered Computing resource through DiRAC, part of the UK’s Science and Technology Facilities Council’s computing facilities.

Kai Hou (Gordon) Yip, Postdoctoral Research Fellow at UCL and Ariel Data Challenge Lead said:

“With the arrival of next-generation instrumentation, astronomers are struggling to keep up with the complexity and volume of incoming exo-planetary data. The NeurIPS data challenge 2022 provides an excellent platform to facilitate cross-disciplinary solutions with AI experts.”

The competition

Winners will be invited to present their solution at the prestigious NeurIPS conference. First prize winning teams will be awarded $2,000 and second prize winners will receive $500.

Winners will also be invited to present their solution to the Ariel consortium.

The competition is supported by the UK Space Agency, European Research Council, European Space Agency and Europlanet Society.

Previous competition

This is the third Ariel Machine Learning Data challenge following successful competitions in 2019 and 2021. The 2021 challenge welcomed 130 participants from across Europe, including entrants from leading academic institutes and AI companies.

This challenge, and its predecessor have taken a bite-sized aspect of a larger problem to help make exoplanet research more accessible to the machine learning community. The challenge is not designed to solve the data analysis issues faced by the mission outright but provides a forum for discussion and to encourage future collaborations.

More details about the competition and how to take part can be found on the Ariel Data Challenge website. Follow @ArielTelescope for more updates.

To continue reading the full Ariel press release, click HERE

Ariel Data Challenge Logo

Ariel Press Release (06/22) – ESA member states sign new Ariel collaboration agreement

European Space Agency (ESA) member states have signed a new agreement on 8 June to confirm roles for the Ariel mission.   

During its four year mission, Ariel will improve our understanding of what exoplanets are made of, how they were formed and how they evolve. Scientific data will be released to the scientific community and general public at regular intervals throughout its planned four-year operational phase.

Ariel, which was proposed by an international consortium led by UCL (University College London), was selected by ESA from 26 proposals put forward to be the next medium class mission in its science programme. A consortium of more than 50 institutes from 17 countries will work together to build the mission’s payload module.

The agreement between ESA member states ensures that the work taking place across the consortium continues to be supported by their national agencies.

Professor Giovanna Tinetti, Principal Investigator and science development lead for Ariel at UCL, said:

“Ariel will be transformational in helping us understand the planets in our galaxy. By studying hundreds of diverse worlds in different environments, we will see our own planet in context, giving us a better sense of why Earth formed as it did.”

Paul Eccleston, Ariel Consortium Programme Manager and Chief Engineer at the Science and Technology Facilities Council’s RAL Space said:

“Ariel is bringing together scientists, engineers and technicians from across Europe to deliver this fantastic mission which will allow us to study planets outside our solar system and understand our place in the universe. I’m proud of the progress the consortium has already made to design the payload. These ties are only set to strengthen as we progress towards launch.”

A payload design review will be completed later this year, with the design expected to be finalised by 2025. A flight acceptance review will be completed in early 2029 ahead of launch later that year.

Find out more from: UK Space Agency
To read the Ariel press release in PDF, click HERE

Artist impression of ESA’s Ariel exoplanet satellite.
Artist impression of ESA’s Ariel exoplanet satellite. Credit: Airbus.

Ariel Press Release (12/2021) – Airbus will build ESA’s Ariel exoplanet satellite

The European Space Agency (ESA) and Airbus have signed a contract to move forward with the design and construction of the Atmospheric Remote-sensing Infrared Exoplanet Large-survey (Ariel). Work on the Ariel payload module by the Ariel Mission Consortium is already well underway and the two teams will be working closely together to deliver the mission for launch in 2029.

 “With this milestone for the Ariel mission we celebrate the continuation of the outstanding relationship with our industry partners to keep Europe at the forefront of excellence in the field of exoplanet research well into the next decade and beyond,” says Günther Hasinger, ESA’s Director of Science.

The contract was celebrated between the two parties with a small ceremony at ESA headquarters in Paris on 6 December.

Airbus will lead the European industrial consortium building the satellite bus. The Toulouse facility in France will be the main site for designing, manufacturing and integrating the spacecraft elements, while Airbus Stevenage in the UK will lead the engineering of the avionics, radio frequency communication and electrical design of the platform.

“Airbus has extensive experience of leading ground-breaking science missions, including Juice, Gaia, Solar Orbiter, Lisa Pathfinder and Cheops, on which we are building for ESA’s latest science mission, Ariel,” said Jean-Marc Nasr, head of Space Systems at Airbus.

The mission’s payload module, which includes a one metre-class cryogenic telescope and associated science instruments, is provided by the Ariel Mission Consortium. The consortium comprises more than 50 institutes from 17 European countries. NASA also contributes to the payload. In 2021 the Consortium completed ten reviews covering each of the payload subsystems to ensure that the teams understand what needs to be built and that the preliminary designs for each part are feasible and, crucially, will work together correctly.

“The international Ariel Mission Consortium been making fantastic progress with the payload. We are looking forward to working closely with Airbus to ensure the payload works perfectly on board the spacecraft. Together we will be enabling amazing new discoveries about planets beyond our Solar System” said Paul Eccleston, Ariel Mission Consortium Project Manager and RAL Space Chief Engineer.

To continue reading the full Ariel press release, click HERE
To read the ESA press release, click HERE

Artist’s impression of Ariel on its way to Lagrange Point 2 (L2). Here, the spacecraft is shielded from the Sun and has a clear view of the whole sky. Image Credit: ESA/STFC RAL Space/UCL/Europlanet-Science Office

Ariel Press Release (09/2021) – Winners announced for the Ariel Data Challenge!

Artificial intelligence (AI) experts from around the world have been competing for the opportunity to help astronomers to explore planets in our local galactic neighbourhood.

The European Space Agency’s Ariel telescope, which launches in 2029, will study the atmospheres of around 1000 planets outside our solar system, known as exoplanets.

Observing faint signals to measure the make-up of exoplanet atmospheres is incredibly challenging and is made even more so by other signals the instrument may pick up. The effect of star activity, like sun spots, and even the noise of the spacecraft itself can obscure the information scientists receive from Ariel.

The Ariel Machine Learning Data Challenge, sponsored by Spaceflux Ltd, was set to harness the expertise of the artificial intelligence community to help disentangle this unwanted noise from the light filtering through exoplanet atmospheres. Over 110 teams from around the world participated with 35 teams submitting viable solutions. The teams represented a mix of academia and AI companies.

The competition winners, ML Analytics, an artificial intelligence company in Portugal, and a team from TU Dortmund University in Germany were able to achieve highly accurate solutions for even the most difficult to observe planets.

To continue reading the full press release, follow this link:
Winners announced for the machine vs stellar and instrument noise data challenge

Credit: ESA/STFC RAL Space/UCL/UK Space Agency/ ATG Medialab

Ariel Press Release (11/2020) – The European Space Agency formally adopts Ariel, the exoplanet explorer

The European Space Agency (ESA) have formally adopted Ariel, the first mission dedicated to study the nature, formation and evolution of exoplanets.

– Ariel has passed major feasibility reviews and has been formally adopted into the program of future missions for implementation.
– It will survey about 1000 planets outside our solar system during its lifetime.
– Ariel will unveil the nature, formation and evolution of a large and assorted sample of planets around different types of stars in our galaxy.

To continue reading the full press release, follow this link:
The European Space Agency formally adopts Ariel, the exoplanet explorer

Artist’s rendering of the Ariel Spacecraft. Credit: Ariel/Science Office

 Ariel Press Release (04/2019) – Ariel Data Challenge Series launched to build global community for exoplanet data solutions

Ariel, a mission to make the first large-scale survey of exoplanet atmospheres, has launched a global competition series to find innovative solutions for the interpretation and analysis of exoplanet data. The first Ariel Data Challenge invites professional and amateur data scientists around the world to use Machine Learning (ML) to remove noise from exoplanet observations caused by starspots and by instrumentation.

To continue reading the full press release, follow this link:
Ariel Data Challenge Launch 2019

The Ariel Data Challenge Series 2019. Credit: ARIEL Consortium

Ariel Press Release (03/2018) –
Ariel selected as ESA’s next medium-class science mission

Ariel, a mission to answer fundamental questions about how planetary systems form and evolve, has been selected by the European Space Agency (ESA) as its next medium-class science mission, due for launch in 2028. During a 4-year mission, Ariel will observe 1000 planets orbiting distant stars and make the first large-scale survey of the chemistry of exoplanet atmospheres. ESA’s Science Programme Committee announced the selection of Ariel from three candidate missions on 21st March 2018.

To continue reading the full press release, follow this link:
Ariel Selection Press Release UK 2018


Ariel will be placed in orbit around the Lagrange Point 2 (L2), a gravitational balance point 1.5 million kilometres beyond the Earth’s orbit around the Sun. Image Credit: ESA/STFC RAL Space/UCL/Europlanet-Science Office


Ariel Press Release (01/2015) –
Mission Announcement

An ambitious European mission is being planned to answer fundamental questions about how planetary systems form and evolve. Ariel will investigate the atmospheres of several hundreds planets orbiting distant stars. It is one of three candidate missions selected last month by the European Space Agency (ESA) for its next medium class science mission, due for launch in 2026. The Ariel mission concept has been developed by a consortium of more than 50 institutes from 12 countries, including UK, France, Italy, Germany, the Netherlands, Poland, Spain, Belgium, Austria, Denmark, Ireland, Portugal. The mission will be presented today at the Pathways 2015 conference in Bern, Switzerland, by Ariel’s Principal Investigator, Prof Giovanna Tinetti of UCL.

“The essential nature of exoplanets is still something of a mystery to us: despite finding nearly 2000 exoplanets we haven’t yet found any discernible pattern linking the presence, size or orbital parameters of a planet to what its parent star is like,” said Tinetti. “If we are going to answer questions, such as how is the chemistry of a planet linked to the environment in which it forms, or is its birth and evolution driven by its host star, we need to study a statistically large sample of exoplanets. This is what Ariel is designed to do.”

During its 4-year mission, Ariel will observe over 500 exoplanets ranging from Jupiter- and Neptune-size down to super-Earths in a wide variety of environments. While some of the planets known by the time of Ariel’s launch may be habitable, the main focus of the mission will be on exotic, hot planets in orbits very close to their star.

Hot exoplanets represent a natural laboratory in which to study the chemistry and formation of exoplanets. In cooler planets, different gases separate out through condensation and sinking into distinct cloud layers. The scorching heat experienced by hot exoplanets overrides these processes and keeps all molecular species circulating throughout the atmosphere.

Ariel will have a meter-class mirror to collect infrared light from distant star systems and to focus it to a spectrometer. This will spread the light into a ‘rainbow’ and extract the chemical fingerprints of gases in the planets’ atmospheres, as the planet passes in front or behind the star.

Ariel will be placed in orbit at Lagrange Point 2 (L2), a gravitational balance point beyond the Earth’s orbit, where the spacecraft is shielded from the Sun and has a clear view of the whole night sky. This will maximise its options for observing exoplanets discovered previously by other missions.

Ariel’s Project Manager, Paul Eccleston, said “STFC RAL Space is excited to be involved in such an ambitious mission, and one which is crucial to the study of how planets form and evolve. Working with such a large consortium means that we will be able to draw on world leading expertise from around Europe to get the very best results for of the mission.”