Unlike the primordial disks around very young (<10 Myr-old) stars, the dusty disks around main sequence stars are tenuous, virtually gas-free, and should have lifetimes much less than the age of the star. So why are they still there? The simplest answer is that these disks are generated by the grinding together of planetesimals that have formed around the star. Debris disks are exciting for a number of reasons, not least because they present a unique source of information about the properties of young planets that are otherwise difficult or impossible to observe.
Debris Disks
Debris Disk Morphology
What do debris disks look like? Images of the nearest and brightest debris disks reveal rings, warps, and asymmetries, with mounting evidence that these irregularities are due to the presence of large planets in the disk. We are studying the debris disks around several nearby stars: the solar analogue HD 107146, the triple-planet host HR 8799, the planet host beta Pictoris, the familiar bright A star Vega, and probably more by the time you read this. For disks shaped by planetary systems, the disk morphology can provide crucial constraints on the masses and orbital radii of the young planets.
