An Earth-like world is one that’s rocky and that orbits a Sun-like, or G-Type, star. The Milky Way has 400 billion stars, with 7 % of them being G-type, meaning that less than six billion stars may have Earth-like planets in our Galaxy.
Astronomy is advancing to the point where we can see planets forming around young stars. This was an unthinkable only a few years ago. It was only two years ago that astronomers captured the first image of a newly-forming planet.
The object, called Fomalhaut b, was first announced in 2008. It was clearly visible in several years of Hubble observations that revealed it was a moving dot. Now it has vanished and scientists seek for a plausible explanation.
The system around HD 158259 star consists of an innermost large rocky planet (a “super-Earth”) and five small gas giants (“mini-Neptunes”) that have exceptionally regular spacing between them.
Cheops (Characterising Exoplanet Satellite), the satellite for the study of the exoplanets of the European Space Agency (Esa), has passed the exams and now it is ready to go to work.
Astronomers have found an exoplanet more than twice the size of Earth to be potentially habitable, opening the search for life to planets significantly larger than Earth but smaller than Neptune.
The habitable-zone planet is one of three orbiting a star known as TOI 700, a cool M dwarf located about 100 light-years from Earth. The candidate planet, TOI 700 d, is is at a distance where temperatures would allow water to exist in liquid form.
CHEOPS stands for the Characterizing Exoplanet Satellite. It’s a partnership between ESA and Switzerland, with 10 other EU states contributing. Its mission is not to find more exoplanets, but to study the ones we already know of.
In the first observation of its kind, astronomers using the Very Large Telescope in Chile have found evidence of a Neptune-size planet orbiting a white dwarf, the collapsed remnant of a Sun-like star that has run out of nuclear fuel.
We get excited when we detect water on another world, which so far hasn’t happened often. But this study shows that the presence of water, though tantalizing and worth pursuing scientifically, guarantees nothing.