Exoplanets are planets located in solar systems other than our own. The first confirmed discovery was made in 1995. Since then, just over 4 300 have been registered by the American National Aeronautics and Space Administration (NASA). In a study published in the research journal Nature, an international team, including researchers from Lund University in Sweden, succeeded in analysing isotope signals from the exoplanet TYC-8778b.
“It is a gas planet located 300 light-years from Earth. We were able for the first time to successfully study an exoplanet’s atmosphere using isotope measurements – it is a milestone”, says Jens Hoeijmakers, astronomy researcher at Lund University.
For the study, the researchers used the European Southern Observatory’s VLT facility (Very Large Telescope) in Chile. Thanks to the captured weak signal, the research team could establish that the atmosphere around TYC-8778b is unusually rich in carbon-13 – a natural and stable isotope of carbon with a nucleus that contains six protons and seven neutrons.
“Isotopes are keys that can provide us with valuable information about conditions at specific places in the universe. The discovery of carbon-13 indicates, among other things, that this planet was formed a very long way from its host star”, states Jens Hoeijmakers.
The gas giant TYC-8778b was discovered in 2019 by the German astronomy researcher Alex Bohn. It is a planet similar to Jupiter and located 150 times farther away from its star than the distance between the Earth and the sun. The chance of life on the planet in question is therefore very small. However, knowledge about the exoplanet’s atmosphere sets the stage for new studies of more Earth-like planets where the chance of extraterrestrial life is greater.
“Isotope measurements of this type are the future. I think they will be the starting shot for obtaining more in-depth knowledge about exoplanets. Using the new method, we can learn more about how and when these remarkable planets were formed”, concludes Jens Hoeijmakers.
In addition to Lund University, the following higher education institutions and organisations took part in the work: the Leiden Observatory, Leiden University, the Max Planck Institute for Astronomy, University of Amsterdam, Jet Propulsion Laboratory, Caltech and KU Leuven.