THE ABSENCE OF COLD DUST AND THE MINERALOGY AND ORIGIN OF THE WARM DUST ENCIRCLING BD +20 307

Journal Article · Mon Jan 10 00:00:00 EST 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/726/2/72· OSTI ID:21567673

Weinberger, A J ^[1]; Becklin, E E; Zuckerman, B ^[2]; Song, I ^[3]

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1. Department of Terrestrial Magnetism, Carnegie Institution of Washington 5241 Broad Branch Road NW, Washington, DC 20015 (United States)
2. Department of Physics and Astronomy, University of California Los Angeles, Box 951547, Los Angeles, CA 90095-1562 (United States)
3. Department of Physics and Astronomy, University of Georgia, Athens, GA 30602-2451 (United States)

Spitzer Space Telescope photometry and spectroscopy of BD +20 307 show that all of the dust around this remarkable Gyr-old spectroscopic binary arises within 1 AU. No additional cold dust is needed to fit the infrared excess. Peaks in the 10 and 20 {mu}m spectrum are well fit with small silicates that should be removed on a timescale of years from the system. This is the dustiest star known for its age, which is {approx}>1 Gyr. The dust cannot arise from a steady-state collisional cascade. A catastrophic collision of two rocky, planetary-scale bodies in the terrestrial zone is the most likely source for this warm dust because it does not require a reservoir of planetesimals in the outer system.

• OSTI ID: 21567673
• Journal Information: Astrophysical Journal, Vol. 726, Issue 2; Other Information: DOI: 10.1088/0004-637X/726/2/72; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COLLISIONS
DUSTS
INTERACTIONS
MATTER
MINERALOGY
ORIGIN
PLANETS
STARS