A solar system including six planets around a star 2,000 light-years away has been spotted by astronomers.
The planets range between two and four-and-a-half times the radius of Earth, and between two and 13 times its mass.
Five of the planets orbit the star closer than Mercury orbits our Sun.
The find, published in Nature, is the first from the latest data release from the Kepler space telescope - which includes details of more than 1,000 additional exoplanet candidates.
The planets are likely to have atmospheres made of light gases, but also likely to be too hot to support life.
The Kepler team released the raw data that led to the discovery as part of its commitment to making its findings publicly available.
Kepler has already yielded evidence of a three-planet system, Kepler-9, and in January the team announced it had spotted the first definitively rocky exoplanet, Kepler-10.
The newly-discovered solar system, around the star Kepler 11, is a rich "laboratory" for studying planetary formation. Its surprising number of planets orbiting so closely together gives astrophysicists a unique system to refine their theories of how planets form.
The find is different from the planetary system HD10180, first announced in August 2010, in which a rich exoplanet system comprising at least five planets orbits a star 127 light-years away. In that study, the "wobble" that the planets' gravity caused on their host star was used to infer their presence; a sixth and seventh planet are yet to be confirmed.
The Kepler telescope, by contrast, performs a more direct observation, measuring the minuscule dimming that occurs when planets pass in front of their host star.
Typically, in these "transit" measurements, the dimmings merely suggest planets; their presence is confirmed by ground-based telescopes that look for the "wobble" - a method known as radial velocity measurements.
In the case of Kepler-11, the planets orbit their host star so close to one another that they have noticeable gravitational effects on each other. These effects rhythmically change the time that each needs to orbit the star, and the authors were able to work out the masses of the planets. BBC News
