Ariel: Exploring the atmospheres of exoplanets
- Launch:
- Mission duration: 4 years with possibility to extend
- Mission status: In development
Monitoring distant and diverse worlds
Ariel (Atmospheric remote-sensing infrared exoplanet large-survey) is a European Space Agency-led mission that will characterize more planets beyond our solar system than ever before. The space telescope will monitor these exoplanets atmosphere, ranging from rocky planets to gas giants, from a point in space called Lagrange 2, 1.5 million kilometres away from Earth, sharing this location with the James Webb Space Telescope. Ariel will study approximately a thousand such planets, measuring the molecules, clouds, winds in their atmospheres and their thermal structures.
Ariel will study exoplanets in two complementary ways: transit and emission spectroscopy.
- Spectroscopy refers to splitting the colours of light, as with a prism. Ariel will focus on visible and infrared light, which are most informative for planets. When a planet transits in front of its host star, light from the star filters through the upper atmosphere of the planet and is imprinted with the signatures of atoms and molecules which can then be observed. This is the best way for astronomers to figure out what exoplanets are made of.
- Emission spectroscopy means studying the light given off by the planet itself. Light tells us about the temperature at different places in the atmosphere.
By combining transit and emission spectroscopy, Ariel will paint a holistic picture of hundreds of exoplanets and their atmospheres.
Scientific objectives
Ariel is designed to:
- Perform a large-scale survey of exoplanets
- Study the chemical composition and temperature of exoplanet atmospheres to better understand planet formation and atmospheric properties
Artist's impression of the ESA's Ariel exoplanet satellite. (Credit: Airbus)
Canada's contribution
Canada will supply components called cryoharnesses, which are crucial electrical data cables, connecting the telescope's complex imaging detector arrays to the spacecraft's computer. Cryoharnesses are optimized to transmit electrical signals without transmitting too much heat. While the detectors operate at very cold temperatures (40K or −230 °C) the computer is at "room temperature
" (293K or 20 °C), therefore the cryoharnesses must be compatible with this challenging range of temperatures.
In fall , ABB Inc. was selected to develop this set of space-qualified power and data cables and their interfaces. ABB Inc. has contributed similar technology to other missions, notably for the James Webb Space Telescope.
For this investment, Canadian scientists will get to participate in important research.
- Dr. Nicolas Cowan has been appointed co-Principal Investigator of the Ariel mission, and will join the ESA's Ariel Science Team. Associate Professor in the departments of Physics and of Earth & Planetary Sciences at McGill University, Cowan studies the atmospheres of exoplanets using infrared telescopes on the ground and in space. He and his team are particularly keen to use the Ariel emission spectra to construct temperature maps of exoplanets.
- Up to 12 Canadian scientists will be invited to join the Ariel Mission Consortium, allowing them to select targets, define science objectives, and gain privileged access to Ariel's data.