Planet the Sun: Jupiter is the largest, at 318 Earth masses, whereas Mercury is the smallest, at 0.055 Earth masses. The planets of the Solar System can be divided into categories based on their composition: An exoplanet (extrasolar planet) is a planet outside the Solar System. In early 1992, radio astronomers Aleksander Wolszczan and Dale Frail announced the discovery of two planets orbiting the pulsar PSR 1257+12. This discovery was confirmed, and is generally considered to be the first definitive detection of exoplanets. These pulsar planets are believed to have formed from the unusual remnants of the supernova that produced the
Gustav Holst horrors". Nevertheless, the composer and critic Colin Matthews recognises even in these apprentice works an "instinctive orchestral flair". Of the few pieces from this period which demonstrate some originality, Matthews pinpoints the G minor String Trio of 1894 (unperformed until 1974) as the first underivative work produced by Holst. Matthews and Imogen Holst each highlight the "Elegy" movement in "The Cotswold Symphony" (1899–1900) as among the more accomplished of the apprentice works, and Imogen discerns glimpses of her father's real self in the 1899 "Suite de ballet" and the "Ave Maria" of 1900. She and Matthews have asserted that Holst