Planets

The NGC 346 cluster with 10 circled stars surrounded by protoplanetary disks (Image NASA, ESA, CSA, STScI, O. C. Jones (UK ATC), G. De Marchi (ESTEC), M. Meixner (USRA))

An article published in “The Astrophysical Journal” reports the results of the study of a group of protoplanetary disks with an age of up to 30 million years, even 10 times older than current models of planet formation predict. A team led by Guido De Marchi of ESA’s European Space Research and Technology Centre used observations conducted with the James Webb space telescope of the cluster NGC 346, in the Small Magellanic Cloud. That region is characterized by a limited amount of elements heavier than hydrogen and helium, just like the early universe. This study confirms that in those conditions, protoplanetary disks can last much longer than astronomers thought.

Artist's concept of the exoplanet TOI-3261 b being struck by stellar wind (Image NASA/JPL-Caltech/K. Miller (Caltech/IPAC))

An article published in “The Astronomical Journal” reports the identification of the exoplanet TOI-3261 b, an ultrahot Neptune very close to its star, one of the very few planets of that type known. A team of researchers used observations conducted with NASA’s TESS space telescope and detections obtained with the ESPRESSO and HARPS instruments to confirm its existence and obtain information on its characteristics. TOI-3261 b orbits in what is known as the Neptune desert precisely because it’s in an area where it’s very rare to find Neptune-type planets. For this reason, it will help to understand the evolution of certain types of planets.

Artist’s impression of the exoplanet Barnard b with Barnard's Star in the background (Image ESO/M. Kornmesser)

An article published in the journal “Astronomy & Astrophysics” reports the identification of an exoplanet smaller than Earth orbiting Barnard’s Star. A team of researchers identified the exoplanet designated as Barnard b using the ESPRESSO instrument installed on ESO’s VLT in Chile. This discovery was later confirmed with other specialized exoplanet-hunting instruments: HARPS, HARPS-N, and CARMENES. The researchers also detected other signatures that suggest the presence of three exoplanet candidates, but follow-up investigations are needed to verify their existence.

An article published in the journal “Nature Astronomy” reports a possible reconstruction of the system of the ultra-cool dwarf star TRAPPIST-1 that led to the current configuration of its seven rocky planets. A team of researchers examined their orbits and in particular their orbital resonances, concluding that the planets formed in two steps in a protoplanetary disk divided into two parts. Initially, this led to the formation of two planetary subsystems and only later did planetary migrations occur with influences between various planets that led to the current situation.

A cutout of the interior of Mars beneath NASA's InSight lander with the dry upper crust and the mid-crust saturated with water

An article published in the journal “Proceedings of the National Academy of Sciences (PNAS)” reports the results of an analysis of seismic data collected on the planet Mars by NASA’s InSight lander that concludes that the mid-crust of Mars could be filled with liquid water that saturates a layer of igneous rock. Vashan Wright and Matthias Morzfeld of the Scripps Institution of Oceanography and Michael Manga of the University of Berkeley used models similar to those used to map aquifers and oil fields to try to understand the composition of deep layers of the Martian subsurface.

The best explanation for the data collected by the InSight mission is that between 11.5 and 20 kilometers deep there’s a layer of igneous rock saturated with liquid water. The depth makes it impossible to reach it but if the entire mid-crust of Mars were made like this, there would be enough water to form an ocean between one and two kilometers deep on the surface.