Solar System 7 light-years away. Compared to many other planetary systems, the Solar System stands out in lacking planets interior to the orbit of Mercury. The known Solar System also lacks super-Earths (Planet Nine could be a super-Earth beyond the known Solar System). Uncommonly, it has only small rocky planets and large gas giants; elsewhere planets of intermediate size are typical—both rocky and gas—so there is no "gap" as seen between the size of Earth and of Neptune (with a radius 3.8 times as large). Also, these super-Earths have closer orbits than Mercury. This led to hypothesis that all planetary systems start
Gustav Holst likens to "unresolved timelessness ... never ending, since space does not end, but drifting away into eternal silence". Apart from his concession with "I Vow to Thee..."', Holst insisted on the unity of the whole work, and opposed the performance of individual movements. Nevertheless, Imogen wrote that the piece had "suffered from being quoted in snippets as background music". During and after the composition of "The Planets", Holst wrote or arranged numerous vocal and choral works, many of them for the wartime Thaxted Whitsun Festivals, 1916–18. They include the "Six Choral Folksongs" of 1916, based on West Country tunes, of