On the Flux of Extrasolar Dust in Earth’s Atmosphere

Micron size extrasolar dust particles have been convincingly detected bysatellites. Larger extrasolar meteoroids (5-35 microns) have most likely beendetected by ground based radar at Arecibo and New Zealand. We present estimatesof the minimum detectable particle sizes and collecting areas for both radarsystems. We show that particles larger than about 10 microns can propagate fortens of parsecs through the interstellar medium, opening up the possibilitythat ground based radar systems can detect AGB stars, young stellar objectssuch as T Tauri stars, and debris disks around Vega-like stars. We provideanalytical and numerical estimates of the ejection velocity in the case of adebris disk interacting with a Jupiter mass planet. We provide rough estimatesof the flux of large micrometeoroids from all three classes of sources. Currentradar systems are unlikely to detect significant numbers of meteors from debrisdisks such as Beta Pictoris. However, we suggest improvements to radar systemsthat should allow for the detection of multiple examples of all three classes.Comment: 62 pages, 8 figures, LaTeX, to appear in Astrophysical Journa