This is then combined with a modelling system for quantifying CO2 emissions down to individual building level.

BBC: US researchers map carbon emissions at street level

They also look very similar to the simulations coming out of Piomas (Pan-Arctic Ice-Ocean Modelling and Assimilation System), an influential computer model that has been used to estimate Arctic sea-ice volume and which has been the basis for several predictions about when summer sea ice might disappear completely.

BBC: Cryosat spots Arctic sea-ice loss in autumn

Dr Murray stressed there was no direct evidence these stars did have Earth-sized planets in orbit about them, but modelling had shown that if sufficient terrestrial material existed in a system it would eventually clump together into bodies as big as the Earth.

BBC: 'Hungry' stars reveal planet presence