Astronomers using the twin 10-meter telescopes at the W. M. Keck Observatory in Hawaii recently explored one of the most compact dust disks ever resolved around another star. If placed in our own solar system, the disk would reach nearly to Jupiter’s orbit. An outer disk that extends hundreds of times farther accompanies the compact inner disk.
The centerpiece of the study is the Keck Interferometer Nuller (KIN), a device that combines light captured by both of the giant telescopes in a way that allows researchers to study faint objects otherwise lost in a star’s brilliant glare.
“This is the first compact disk detected by the KIN, and a demonstration of its ability to detect dust clouds a hundred times smaller than a conventional telescope can see,” said Christopher Stark, an astronomer at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who led the research team.
By merging the beams from both telescopes in a particular way, the KIN essentially creates a precise blind spot that blocks unwanted starlight but allows faint adjacent signals — such as the light from dusty disks surrounding the star — to pass through.
In April 2007, the team targeted 51 Ophiuchi, a young, hot, B-type star about 410 light-years away in the constellation Ophiuchus. Astronomers suspect the star and its disks represent a rare, nearby example of a young planetary system just entering the last phase of planet formation, although it is not yet known whether planets have formed there.
