Image: Artist’s impression of the disc of dust and gas around a brown dwarf

Description: Rocky planets are thought to form through the random collision and sticking together of what are initially microscopic particles in the disc of material around a star. These tiny grains, known as cosmic dust, are similar to very fine soot or sand. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have for the first time found that the outer region of a dusty disc encircling a brown dwarf — a star-like object, but one too small to shine brightly like a star — also contains millimetre-sized solid grains like those found in denser discs around newborn stars. The surprising finding challenges theories of how rocky, Earth-scale planets form, and suggests that rocky planets may be even more common in the Universe than expected.
Title: Artist’s impression of the disc of dust and gas around a brown dwarf
Credit: http://www.eso.org/public/images/eso1248a/
Author: ALMA (ESO/NAOJ/NRAO)/M. Kornmesser (ESO)
Usage Terms: Creative Commons Attribution 4.0
License: CC BY 4.0
License Link: http://creativecommons.org/licenses/by/4.0
Attribution Required?: Yes