HD 40307 b [SEP] constellation
HD 40307 b
HD 40307 b is an extrasolar planet orbiting the star HD 40307, located 42 light-years away in the direction of the southern constellation Pictor. The planet was discovered by the radial velocity method, using the European Southern Obervatory's HARPS apparatus, in June 2008. It is the second smallest of the planets orbiting the star, after HD 40307 e. The planet is of interest as this star has relatively low metallicity, supporting a hypothesis that different metallicities in protostars determine what kind of planets they will form
40307 d was discovered through the Doppler spectroscopy method, which functions by measuring the variations in radial velocity in a star produced by the gravitational effect of orbiting exoplanets. The radial velocities were measured by the High Accuracy Radial Velocity Planet Searcher spectrography system (HARPS) at the La Silla Observatory in Chile's Atacama Desert. The other less massive planets orbiting HD 40307 were discovered in the same way: HD 40307 b and HD 40307 c first, and then HD 40307 e, HD 40307 f, and HD 40307 g. The discovery