Howe many planets around M dwarf stars? The study: “HADES RV Programme with HARPS-N at TNG. XV. Planetary occurrence rates around early-M dwarfs” of M. Pinamonti (INAF-OATo) recently appeared on A&A

M dwarf stars, with temperature ranging between 2400 and 3900 K and mass between 0.08 and 0.7 solar masses, are ideal targets for the search of exoplanets. This because the most important techniques to search for exoplanets are more effective when applied to stars of this spectral type than to more massive stars. For instance, the method of radial velocity

» Read more

A super-Earth for the star GJ 9689. The study: “HADES RV programme with HARPS-N at TNG. XIV. A candidate super-Earth orbiting the M-dwarf GJ 9689 with a period close to half the stellar rotation period” of J. Maldonado (INAF-OAPA) recently appeared on A&A

M stars are the most common stars in the Universe. They have a mass ranging between 0.6 and 0.08 Solar masses in the main sequence, and an effective temperature ranging between 3900 K and 2400 K. In these stars, the signals due to the presence of planets, such as radial velocity (periodic oscillations of the star from its rest position

» Read more

A sub-Neptunian exoplanet around the star GJ 720 A. The study: “HADES RV Programme with HARPS-N at TNG XIII. A sub-Neptune around the M dwarf GJ 720 A” of E. González-Álvarez (CSIC-INTA) recently appeared on A&A

About 19.3% of the 4001 exoplanets confirmed to date were discovered with the technique of the radial velocity (from https://exoplanets.nasa.gov/). This method consists in using time series of spectroscopic observations in order to measure the periodic oscillations of the position of stars due to the presence of orbiting exoplanets. In fact, in a planetary system both the planets and the

» Read more

A new super-Earth around an M star. The study: “HADES RV program with HARPS-N at the TNG. IX: A super-Earth around the M dwarf Gl 686” of L. Affer (INAF-OAPA) recently appeared on A&A

Low mass star (in particular M-type star, with a mass between 0.075 and 0.5 solar masses) are typical targets for the search and study of exoplanets. In these stars, in fact, the radial velocity method is more efficient than in stars with higher mass. Radial velocity consists in detecting periodic oscillations in the stellar spectra due to the motion of

» Read more

A new super-Earth discovered thanks to Harps-N. The study “HADES RV Programme with HARPS-N at TNG. GJ 3942 b behind dominant activity signals” of M. Perger published by A&A

The analysis of radial velocity is one of the two main methods used to detect exoplanets. This method consists in measuring the Doppler effect on stellar spectra deriving the velocity component along the line of sight (the radial velocity). If the star has a planet, they both orbit around the common center of mass,  producing periodic oscillations of the osberved

» Read more