ESA's Ariel mission will boldly spot exoplanets not seen before
The meter-long telescope expected to launch in 2028
The European Space Agency is launching a mission to find out how planets form and how life emerges in space, it announced on Tuesday.
Ariel, also known as the Atmospheric Remote-sensing Infrared Exoplanet Large-survey mission, will narrow down on the search for exoplanets and is expected to launch in 2028.
Other spacecraft such as NASA’s Kepler Space Telescope have already discovered thousands of exoplanet candidates. Several of them have caught the attention of astronomers, as they have the potential to be rocky and lie within the habitable zone of their host star. But it’s difficult to find out much information beyond their size, mass and orbit.
“There is a gap in our knowledge of how the planet’s chemistry is linked to the environment where it formed, or whether the type of host star drives the physics and chemistry of the planet’s evolution,” ESA said in a statement.
Ariel’s telescope will operate at infrared and visible light, and will probe a planet’s atmosphere using infrared spectroscopy. It will sniff out the chemical signatures for vital ingredients needed for life to emerge as the exoplanet passes in front of its parent star during orbit.
During the transit, the star’s light will be partially blocked and as it dims Ariel can measure the abundance of chemicals at a precision level of 10-100 parts per million relative to the star.
It will detect signs of water vapor, carbon dioxide, methane and metallic compounds on warm and hot planets on roughly 1,000 exoplanet types, ranging from super-Earths – planets with larger masses than Earth but smaller than Uranus and Neptune – to gas giants like Jupiter and Saturn.
Ariel will also analyse the cloud dynamics and monitor daily and seasonal changes in the atmosphere for planets that display especially promising signs for life.
Günther Hasinger, ESA Director of Science, said Ariel “is a logical next step in exoplanet science”.
“[It’ll allow] us to progress on key science questions regarding their formation and evolution, while also helping us to understand Earth's place in the universe."
Ariel was chosen as ESA’s fourth medium-sized mission after the Huygens mission to Titan, one of Saturn’s moon; INTEGRAL, a gamma ray space observatory; and Planck, which studied the cosmic microwave background radiation.
The Ariel spacecraft is expected to be launched on ESA’s new Ariane 6 rocket from the spaceport in Kourou, French Guiana, in 2028. The satellite’s design is yet to be defined.
For those that can’t wait another ten years for some exoplanet hunting action, NASA will be launching TESS, the The Transiting Exoplanet Survey Satellite, in May later this year as Kepler appears to be running low on gas and will retire soon. ®