The first near-infrared image of a dust ring around a young, nearby star has been taken by the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) on board the Hubble Space Telescope. The image may give astronomer Glenn Schneider and his colleagues a new look at early planet formation (Astrophys. J. 513, L127- L130; 1999).

Planets are thought to condense out of the disks of dust and gas surrounding newborn stars by a process of accretion— in which small particles collide and stick together. Such circumstellar disks are hard to see, because the glare from the central star outshines the weaker, reflected light from the disk. This particular image was captured using a coronagraphic camera on NICMOS to block out the glare of the star (grey circle on the image).

This disk is unusual as it is only 1.6 billion miles wide (the ring diameter is 13 billion miles), leaving a large dust-free area inside the ring. The much smaller rings found around planets such as Saturn are held in place by the gravitational force of moons orbiting nearby. The narrowness of this stellar ring implies that it may be confined by one or more unseen bodies — probably new planets. Without some mechanism to keep them intact, dust rings around stars would spread outwards, reducing their ability to form planets.

The colour of the ring is somewhat reddish (scale bar gives flux density in μJy per pixel), showing that it is made up of grains several μm in size, which is larger than typical interstellar dust. This stellar ring is surprisingly young, indicating that planets may have formed in less than ten million years.