Probing the terrestrial regions of planetary systems: Warm debris disks with emission features

Nicholas P. Ballering, George H. Rieke, András Gáspár

Research output: Contribution to journalArticlepeer-review

23 Scopus citations


Observations of debris disks allow for the study of planetary systems, even where planets have not been detected. However, debris disks are often only characterized by unresolved infrared excesses that resemble featureless blackbodies, and the location of the emitting dust is uncertain due to a degeneracy with the dust grain properties. Here, we characterize the Spitzer Infrared Spectrograph spectra of 22 debris disks exhibiting 10 μm silicate emission features. Such features arise from small warm dust grains, and their presence can significantly constrain the orbital location of the emitting debris. We find that these features can be explained by the presence of an additional dust component in the terrestrial zones of the planetary systems, i.e., an exozodiacal belt. Aside from possessing exozodiacal dust, these debris disks are not particularly unique; their minimum grain sizes are consistent with the blowout sizes of their systems, and their brightnesses are comparable to those of featureless warm debris disks. These disks are in systems of a range of ages, though the older systems with features are found only around A-type stars. The features in young systems may be signatures of terrestrial planet formation. Analyzing the spectra of unresolved debris disks with emission features may be one of the simplest and most accessible ways to study the terrestrial regions of planetary systems.

Original languageEnglish (US)
Article number57
JournalAstrophysical Journal
Issue number1
StatePublished - Sep 20 2014


  • circumstellar matter
  • infrared: stars
  • interplanetary medium
  • zodiacal dust

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Probing the terrestrial regions of planetary systems: Warm debris disks with emission features'. Together they form a unique fingerprint.

Cite this