Evidence of Rocky Planetesimals Orbiting Two Hyades Stars

Abstract

The Hyades is the nearest open cluster, relatively young and containing numerous A-type stars; its known age, distance, and metallicity make it an ideal site to study planetary systems around 2-3 Msun stars at an epoch similar to the late heavy bombardment. Hubble Space Telescope far-ultraviolet spectroscopy strongly suggests ongoing, external metal pollution in two remnant Hyads. For ongoing accretion in both stars, the polluting material has log[n(Si)/n(C)] > 0.2, is more carbon deficient than chondritic meteorites, and is thus rocky. These data are consistent with a picture where rocky planetesimals and small planets have formed in the Hyades around two main-sequence A-type stars, whose white dwarf descendants bear the scars. These detections via metal pollution are shown to be equivalent to infrared excesses of Lir/L* ~ 1e-6 in the terrestrial zone of the stars.

7 pages, 3 figures, 2 tables, accepted to MNRAS

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Cited by in corpus (12)

• The frequency of planetary debris around young white dwarfs
• The imprint of exoplanet formation history on observable present-day spectra of hot Jupiters
• Circumstellar Debris and Pollution at White Dwarf Stars
• Spectroscopic Evolution of Disintegrating Planetesimals: Minutes to Months Variability in the Circumstellar Gas Associated with WD 1145+017
• Solar Abundances of Rock Forming Elements, Extreme Oxygen and Hydrogen in a Young Polluted White Dwarf
• Relentless and Complex Transits from a Planetesimal Debris Disk
• How do disks and planetary systems in high-mass open clusters differ from those around field stars?
• Review of scientific topics for Millimetron space observatory
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• Interstellar Meteors from Tidal Disruption of Rocky Planets on Eccentric Orbits Around M Dwarfs