The hunt for exoplanets is enriched by a new discovery, this time absolutely unprecedented: an exoplanet with (for now) truly unique characteristics.
The exoplanet, called 'Nu2 Wolves d' is located 50 light-years away in the constellation Lupus, around a star called Nu2 Lupi. It is about 2,5 times the size of the Earth and almost 9 times its mass.
How was Nu2 Lupi discovered d
The scientists who published the study used measurements with archival data from other observatories and numerical models to characterize the density and composition of the exoplanet and its neighbors. They discovered that the planet has a rocky interior, and much more water than the Earth. However, water is not liquid; instead of taking in high-pressure ice or high-temperature steam, making planets uninhabitable.
Swiss astronomers had already announced in 2019 the detection of three exoplanets with masses between those of Earth and Neptune (17 times the Earth) and it takes 12, 28 and 107 days to circle their parent star.
Yann Alibert, professor of astrophysics at the University of Bern and co-author of the study, said: “We already knew this for the two inner planets, which led us to target CHEOPS at the star system in the first place. The third planet is quite far from the star: no one expected to see its transit!”
It was a turning point. It is the first time that an exoplanet with a revolution period of more than 100 days has been spotted passing a star bright enough to be visible to the naked eye."
Yann Alibert
Because it is a unique discovery
David Ehrenreich, professor at the University of Geneva and CHEOPS mission scientist, who co-signed the study, says: “Due to its relatively long period, the amount of stellar radiation reaching the exoplanet is mild compared to many other exoplanets discovered. The less radiation a planet receives, the less it changes over time. Therefore, a planet with a long period could have retained more information about its origin."
So far, the few astronomers of these exoplanets they had found faint orbiting stars. In other words: little of their light reaches Earth and therefore makes them difficult to study. Not this time: Because its bright host star is close enough to us, the exoplanet is easier to study. This makes it a golden target for future studies with no known equivalent.
David Ehrenreich
An exoplanet that does Photobombing
Photobomb is a term for an object when it suddenly enters the camera's field of view while taking a photograph. The same case happened with CHEOPS. The satellite was photographing a planetary system 50 light years away and suddenly spotted this exoplanet that “ruined the photo,” but it turned out that way.
The team was led by the Universities of Geneva and Bern and by members of the PlanetS National Research Competence Center.
