Detection of large grains in the coma of Comet C/2001 A2 (LINEAR) from Arecibo radar observations

Michael C. Nolan; John K. Harmon; Ellen S. Howell; Donald B. Campbell; Jean Luc Margot

doi:10.1016/j.icarus.2005.11.010

Detection of large grains in the coma of Comet C/2001 A2 (LINEAR) from Arecibo radar observations

Michael C. Nolan, John K. Harmon, Ellen S. Howell, Donald B. Campbell, Jean Luc Margot

Research output: Contribution to journal › Article › peer-review

12 Scopus citations

Abstract

Arecibo S-band (λ = 13 cm) radar observations of Comet C/2001 A2 (LINEAR) on 2001 July 7-9 showed a strong echo from large coma grains. This echo was significantly depolarized. This is the first firm detection of depolarization in a grain-coma radar echo and indicates that the largest grains are at least λ/2π or 2 cm in radius. The grains are moving at tens of m s^-1 with respect to the nucleus. The nondetection of the nucleus places an upper limit of 3 km on its diameter. The broad, asymmetric echo power spectrum suggests a fan of grains that have a steep (differential number ∼a^-4) size distribution at cm-scales, though the observed fragmentation of this comet complicates that picture.

Original language	English (US)
Pages (from-to)	432-441
Number of pages	10
Journal	Icarus
Volume	181
Issue number	2
DOIs	https://doi.org/10.1016/j.icarus.2005.11.010
State	Published - Apr 2006
Externally published	Yes

Keywords

Comets
Radar

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

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10.1016/j.icarus.2005.11.010

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@article{ce9ad56171374a7282d8c11e1bf53564,

title = "Detection of large grains in the coma of Comet C/2001 A2 (LINEAR) from Arecibo radar observations",

abstract = "Arecibo S-band (λ = 13 cm) radar observations of Comet C/2001 A2 (LINEAR) on 2001 July 7-9 showed a strong echo from large coma grains. This echo was significantly depolarized. This is the first firm detection of depolarization in a grain-coma radar echo and indicates that the largest grains are at least λ/2π or 2 cm in radius. The grains are moving at tens of m s-1 with respect to the nucleus. The nondetection of the nucleus places an upper limit of 3 km on its diameter. The broad, asymmetric echo power spectrum suggests a fan of grains that have a steep (differential number ∼a-4) size distribution at cm-scales, though the observed fragmentation of this comet complicates that picture.",

keywords = "Comets, Radar",

author = "Nolan, {Michael C.} and Harmon, {John K.} and Howell, {Ellen S.} and Campbell, {Donald B.} and Margot, {Jean Luc}",

note = "Funding Information: The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, which is operated by Cornell University under a cooperative agreement with the National Science Foundation. We thank Mark Sykes and Lance Benner for helpful reviews. ",

year = "2006",

month = apr,

doi = "10.1016/j.icarus.2005.11.010",

language = "English (US)",

volume = "181",

pages = "432--441",

journal = "Icarus",

issn = "0019-1035",

publisher = "Academic Press Inc.",

number = "2",

}

TY - JOUR

T1 - Detection of large grains in the coma of Comet C/2001 A2 (LINEAR) from Arecibo radar observations

AU - Nolan, Michael C.

AU - Harmon, John K.

AU - Howell, Ellen S.

AU - Campbell, Donald B.

AU - Margot, Jean Luc

N1 - Funding Information: The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, which is operated by Cornell University under a cooperative agreement with the National Science Foundation. We thank Mark Sykes and Lance Benner for helpful reviews.

PY - 2006/4

Y1 - 2006/4

N2 - Arecibo S-band (λ = 13 cm) radar observations of Comet C/2001 A2 (LINEAR) on 2001 July 7-9 showed a strong echo from large coma grains. This echo was significantly depolarized. This is the first firm detection of depolarization in a grain-coma radar echo and indicates that the largest grains are at least λ/2π or 2 cm in radius. The grains are moving at tens of m s-1 with respect to the nucleus. The nondetection of the nucleus places an upper limit of 3 km on its diameter. The broad, asymmetric echo power spectrum suggests a fan of grains that have a steep (differential number ∼a-4) size distribution at cm-scales, though the observed fragmentation of this comet complicates that picture.

AB - Arecibo S-band (λ = 13 cm) radar observations of Comet C/2001 A2 (LINEAR) on 2001 July 7-9 showed a strong echo from large coma grains. This echo was significantly depolarized. This is the first firm detection of depolarization in a grain-coma radar echo and indicates that the largest grains are at least λ/2π or 2 cm in radius. The grains are moving at tens of m s-1 with respect to the nucleus. The nondetection of the nucleus places an upper limit of 3 km on its diameter. The broad, asymmetric echo power spectrum suggests a fan of grains that have a steep (differential number ∼a-4) size distribution at cm-scales, though the observed fragmentation of this comet complicates that picture.

KW - Comets

KW - Radar

UR - http://www.scopus.com/inward/record.url?scp=33645852863&partnerID=8YFLogxK

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U2 - 10.1016/j.icarus.2005.11.010

DO - 10.1016/j.icarus.2005.11.010

M3 - Article

AN - SCOPUS:33645852863

SN - 0019-1035

VL - 181

SP - 432

EP - 441

JO - Icarus

JF - Icarus

IS - 2

ER -

Detection of large grains in the coma of Comet C/2001 A2 (LINEAR) from Arecibo radar observations

Abstract

Keywords

ASJC Scopus subject areas

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