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Simulations show that the system of three Neptune-mass planets is in a dynamically stable configuration, with theoretical calculations favouring a mainly rocky composition for both inner planets, but a significant gaseous envelope surrounding a rocky/icy core for the outer planet.

The detection of an Earth-mass planet orbiting our neighbour star α Centauri B is reported; the planet has an orbital period of 3.236 days and is about 0.04 astronomical units from the star.

A population of extrasolar planets has been uncovered with minimum masses of 1.9–10 times the Earth's mass, called super-Earths, but atmospheric studies can be precluded by the distance and size of their stars. Here, observations of the transiting planet GJ 1214b are reported; it has a mass 6.55 times that of the Earth and a radius 2.68 times the Earth's radius. The star is small and only 13 parsecs away, permitting the study of the planetary atmosphere with current observatories.

The radial-velocity technique could detect a small gas giant orbiting a binary star and determine its mass: 65.2 ± 11.8 Earth masses. The system also hosts a smaller inner planet, making it one of the few known multiplanetary circumbinary systems.

Absorption lines of iron in the dayside atmosphere of an ultrahot giant exoplanet disappear after travelling across the nightside, showing that the iron has condensed during its travel.

Observations of TOI-849b reveal a radius smaller than Neptune’s but a large mass of about 40 Earth masses, indicating that the planet is the remnant core of a gas giant.

The authors find that a nearby planetary system has two terrestrial planets that transit in front of their star (from our perspective). Transiting terrestrial planets are sought after, as they can be characterized in detail, including their atmospheres. Having two in the same system is very rare.

Three planets orbit the Sun-like star ν² Lupi. CHEOPS data show that all of them are transiting and show remarkable diversity. In particular, dry and gas-poor inner planet b has experienced extensive atmospheric loss, while planets c and d are water rich and have a small gaseous envelope of primordial origin.

A low-mass star that is just 12 parsecs away from Earth is shown to be transited by an Earth-sized planet, GJ 1132b, which probably has a rock/iron composition and might support a substantial atmosphere.

Data from the Kepler spacecraft and the HARPS-N ground-based spectrograph indicate that the extrasolar planet Kepler-78b has a mean density similar to that of Earth and imply that it is composed of rock and iron.

In the ultraviolet spectrum, the Neptune-mass exoplanet GJ 436b is shown to have transit depths far greater than those seen in the optical spectrum, indicating that it is surrounded and trailed by a large cloud composed mainly of hydrogen atoms.

LTT 9779 b is Neptune-sized planet rotating around its star with a period of 0.79 days and an equilibrium temperature of 2,000 K. It is not clear how it retained its atmospheric envelope, which contains ~10% of H/He, as it should have been photoevaporated by now.

Kepler-107 b and c have the same radius but, contrary to expectations, the outermost Kepler-107 c is much denser. This difference cannot be explained by photoevaporation by stellar high-energy particle flux and it suggests that Kepler-107 c experienced a giant impact event.