HD 40307

HD 40307 was observed during or before 1900 as part of the Cape Photographic Durchmusterung. The designation HD 40307 is from the Henry Draper Catalogue, which is based on spectral classifications made between 1911 and 1915 by Annie Jump Cannon and her co-workers, and was published between 1918 and 1924. == Characteristics ==

As a K-type star, HD 40307 emits orange-tinted light. It came within 6.4 light-years of the Sun about 413,000 years ago. == Planetary system ==

A planetary system around HD 40307 contains four confirmed planets and two other possible planets, all within of the star. After spending five years observing the star, the European Organisation for Astronomical Research in the Southern Hemisphere (ESO) announced that they had discovered three super-Earths in orbit around HD 40307 in June 2008. All three planets were detected by the radial velocity method, using the HARPS spectrograph system. In 2012, an independent analysis carried out by a team of astronomers led by Mikko Tuomi of the University of Hertfordshire confirmed the existence of these planets and found an additional three planets in the systems. Five of the planets orbit very close to the star, The outermost planet orbits at a distance similar to the distance of Venus to the Sun and is situated well in the system's liquid water habitable zone. The most recent discovery also indicates via dynamical analysis that the true planetary masses can not be much higher than their minimum masses. == See also ==