A SURVEY of the sky has spotted what may be the largest object discovered in the solar system since Pluto was found in 1930.
Tentatively called 2004 DW, the object is part of the Kuiper belt – a collection of icy bodies beyond Neptune. The only objects clearly visible at that distance are Pluto and its moon Charon, as both have icy surfaces that reflect roughly half the incident sunlight. But most Kuiper Belt objects are darker, reflecting only about 9 per cent of sunlight, says Chad Trujillo of the Gemini Observatory, who works on the Caltech sky survey. If…
