Asteroid (101955) 1999 RQ36: Spectroscopy from 0.4 to 2.4μm and meteorite analogs

Beth Ellen Clark, Richard P. Binzel, Ellen S. Howell, Edward A. Cloutis, Maureen Ockert-Bell, Phil Christensen, Maria Antonietta Barucci, Francesca DeMeo, Dante Lauretta, Harold Connolly, Alicia Soderberg, Carl Hergenrother, Lucy Lim, Josh Emery, Michael Mueller

Research output: Contribution to journalArticle

83 Citations (Scopus)

Abstract

We present reflectance spectra from 0.4 to 2.4μm of Asteroid (101955) 1999 RQ36, the target of the OSIRIS-REx spacecraft mission. The visible spectral data were obtained at the McDonald Observatory 2.1-m telescope with the ES2 spectrograph. The infrared spectral data were obtained at the NASA Infrared Telescope Facility using the SpeX instrument. The average visible spectrum is combined with the average near-infrared wavelength spectrum to form a composite spectrum. We use three methods to constrain the compositional information in the composite spectrum of Asteroid (101955) 1999 RQ36 (hereafter RQ36). First, we perform a least-squares search for meteorite spectral analogs using 15,000 spectra from the RELAB database. Three most likely meteorite analogs are proposed based on the least-squares search. Next, six spectral parameters are measured for RQ36 and their values are compared with the ranges in parameter values of the carbonaceous chondrite meteorite classes. A most likely meteorite analog group is proposed based on the depth of overlap in parameter values. The results of the least-squares search and the parametric comparisons point to CIs and/or CMs as the most likely meteorite analogs for RQ36, and COs and CHs as the least likely. RQ36 has a spectrally " blue" continuum slope that is also observed in carbonaceous chondrites containing magnetite. We speculate that RQ36 is composed of a " CM1" -like material. Finally, we compare RQ36 to other B-type asteroids measured by Clark et al. (Clark, B.E. et al. [2010]. J. Geophys. Res. 115, E06005). The results of this comparison are inconclusive. RQ36 is comparable to Themis spectral properties in terms of its albedo, visible spectrum, and near-infrared spectrum from 1.1 to 1.45μm. However, RQ36 is more similar to Pallas in terms of its near-infrared spectrum from 1.6 to 2.3μm. Thus it is possible that B-type asteroids form a spectral continuum and that RQ36 is a transitional object, spectrally intermediate between the two end-members. This is particularly interesting because Asteroid 24 Themis was recently discovered to have H2O ice on the surface (Rivkin, A., Emery, J. [2010]. Nature 464, 1322-1323; Campins, H. et al. [2010a]. Nature 464, 1320-1321).

Original languageEnglish (US)
Pages (from-to)462-475
Number of pages14
JournalIcarus
Volume216
Issue number2
DOIs
StatePublished - Dec 2011

Fingerprint

meteorites
asteroids
asteroid
meteorite
spectroscopy
analogs
carbonaceous chondrites
visible spectrum
near infrared
carbonaceous chondrite
infrared spectra
continuums
infrared telescopes
composite materials
OSIRIS
albedo
magnetite
spectrographs
observatories
spacecraft

Keywords

  • Asteroids
  • Asteroids, Composition

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Clark, B. E., Binzel, R. P., Howell, E. S., Cloutis, E. A., Ockert-Bell, M., Christensen, P., ... Mueller, M. (2011). Asteroid (101955) 1999 RQ36: Spectroscopy from 0.4 to 2.4μm and meteorite analogs. Icarus, 216(2), 462-475. https://doi.org/10.1016/j.icarus.2011.08.021

Asteroid (101955) 1999 RQ36 : Spectroscopy from 0.4 to 2.4μm and meteorite analogs. / Clark, Beth Ellen; Binzel, Richard P.; Howell, Ellen S.; Cloutis, Edward A.; Ockert-Bell, Maureen; Christensen, Phil; Barucci, Maria Antonietta; DeMeo, Francesca; Lauretta, Dante; Connolly, Harold; Soderberg, Alicia; Hergenrother, Carl; Lim, Lucy; Emery, Josh; Mueller, Michael.

In: Icarus, Vol. 216, No. 2, 12.2011, p. 462-475.

Research output: Contribution to journalArticle

Clark, BE, Binzel, RP, Howell, ES, Cloutis, EA, Ockert-Bell, M, Christensen, P, Barucci, MA, DeMeo, F, Lauretta, D, Connolly, H, Soderberg, A, Hergenrother, C, Lim, L, Emery, J & Mueller, M 2011, 'Asteroid (101955) 1999 RQ36: Spectroscopy from 0.4 to 2.4μm and meteorite analogs', Icarus, vol. 216, no. 2, pp. 462-475. https://doi.org/10.1016/j.icarus.2011.08.021
Clark BE, Binzel RP, Howell ES, Cloutis EA, Ockert-Bell M, Christensen P et al. Asteroid (101955) 1999 RQ36: Spectroscopy from 0.4 to 2.4μm and meteorite analogs. Icarus. 2011 Dec;216(2):462-475. https://doi.org/10.1016/j.icarus.2011.08.021
Clark, Beth Ellen ; Binzel, Richard P. ; Howell, Ellen S. ; Cloutis, Edward A. ; Ockert-Bell, Maureen ; Christensen, Phil ; Barucci, Maria Antonietta ; DeMeo, Francesca ; Lauretta, Dante ; Connolly, Harold ; Soderberg, Alicia ; Hergenrother, Carl ; Lim, Lucy ; Emery, Josh ; Mueller, Michael. / Asteroid (101955) 1999 RQ36 : Spectroscopy from 0.4 to 2.4μm and meteorite analogs. In: Icarus. 2011 ; Vol. 216, No. 2. pp. 462-475.
@article{c2f10b9c449c4b6a96ae437ea7b9e673,
title = "Asteroid (101955) 1999 RQ36: Spectroscopy from 0.4 to 2.4μm and meteorite analogs",
abstract = "We present reflectance spectra from 0.4 to 2.4μm of Asteroid (101955) 1999 RQ36, the target of the OSIRIS-REx spacecraft mission. The visible spectral data were obtained at the McDonald Observatory 2.1-m telescope with the ES2 spectrograph. The infrared spectral data were obtained at the NASA Infrared Telescope Facility using the SpeX instrument. The average visible spectrum is combined with the average near-infrared wavelength spectrum to form a composite spectrum. We use three methods to constrain the compositional information in the composite spectrum of Asteroid (101955) 1999 RQ36 (hereafter RQ36). First, we perform a least-squares search for meteorite spectral analogs using 15,000 spectra from the RELAB database. Three most likely meteorite analogs are proposed based on the least-squares search. Next, six spectral parameters are measured for RQ36 and their values are compared with the ranges in parameter values of the carbonaceous chondrite meteorite classes. A most likely meteorite analog group is proposed based on the depth of overlap in parameter values. The results of the least-squares search and the parametric comparisons point to CIs and/or CMs as the most likely meteorite analogs for RQ36, and COs and CHs as the least likely. RQ36 has a spectrally {"} blue{"} continuum slope that is also observed in carbonaceous chondrites containing magnetite. We speculate that RQ36 is composed of a {"} CM1{"} -like material. Finally, we compare RQ36 to other B-type asteroids measured by Clark et al. (Clark, B.E. et al. [2010]. J. Geophys. Res. 115, E06005). The results of this comparison are inconclusive. RQ36 is comparable to Themis spectral properties in terms of its albedo, visible spectrum, and near-infrared spectrum from 1.1 to 1.45μm. However, RQ36 is more similar to Pallas in terms of its near-infrared spectrum from 1.6 to 2.3μm. Thus it is possible that B-type asteroids form a spectral continuum and that RQ36 is a transitional object, spectrally intermediate between the two end-members. This is particularly interesting because Asteroid 24 Themis was recently discovered to have H2O ice on the surface (Rivkin, A., Emery, J. [2010]. Nature 464, 1322-1323; Campins, H. et al. [2010a]. Nature 464, 1320-1321).",
keywords = "Asteroids, Asteroids, Composition",
author = "Clark, {Beth Ellen} and Binzel, {Richard P.} and Howell, {Ellen S.} and Cloutis, {Edward A.} and Maureen Ockert-Bell and Phil Christensen and Barucci, {Maria Antonietta} and Francesca DeMeo and Dante Lauretta and Harold Connolly and Alicia Soderberg and Carl Hergenrother and Lucy Lim and Josh Emery and Michael Mueller",
year = "2011",
month = "12",
doi = "10.1016/j.icarus.2011.08.021",
language = "English (US)",
volume = "216",
pages = "462--475",
journal = "Icarus",
issn = "0019-1035",
publisher = "Academic Press Inc.",
number = "2",

}

TY - JOUR

T1 - Asteroid (101955) 1999 RQ36

T2 - Spectroscopy from 0.4 to 2.4μm and meteorite analogs

AU - Clark, Beth Ellen

AU - Binzel, Richard P.

AU - Howell, Ellen S.

AU - Cloutis, Edward A.

AU - Ockert-Bell, Maureen

AU - Christensen, Phil

AU - Barucci, Maria Antonietta

AU - DeMeo, Francesca

AU - Lauretta, Dante

AU - Connolly, Harold

AU - Soderberg, Alicia

AU - Hergenrother, Carl

AU - Lim, Lucy

AU - Emery, Josh

AU - Mueller, Michael

PY - 2011/12

Y1 - 2011/12

N2 - We present reflectance spectra from 0.4 to 2.4μm of Asteroid (101955) 1999 RQ36, the target of the OSIRIS-REx spacecraft mission. The visible spectral data were obtained at the McDonald Observatory 2.1-m telescope with the ES2 spectrograph. The infrared spectral data were obtained at the NASA Infrared Telescope Facility using the SpeX instrument. The average visible spectrum is combined with the average near-infrared wavelength spectrum to form a composite spectrum. We use three methods to constrain the compositional information in the composite spectrum of Asteroid (101955) 1999 RQ36 (hereafter RQ36). First, we perform a least-squares search for meteorite spectral analogs using 15,000 spectra from the RELAB database. Three most likely meteorite analogs are proposed based on the least-squares search. Next, six spectral parameters are measured for RQ36 and their values are compared with the ranges in parameter values of the carbonaceous chondrite meteorite classes. A most likely meteorite analog group is proposed based on the depth of overlap in parameter values. The results of the least-squares search and the parametric comparisons point to CIs and/or CMs as the most likely meteorite analogs for RQ36, and COs and CHs as the least likely. RQ36 has a spectrally " blue" continuum slope that is also observed in carbonaceous chondrites containing magnetite. We speculate that RQ36 is composed of a " CM1" -like material. Finally, we compare RQ36 to other B-type asteroids measured by Clark et al. (Clark, B.E. et al. [2010]. J. Geophys. Res. 115, E06005). The results of this comparison are inconclusive. RQ36 is comparable to Themis spectral properties in terms of its albedo, visible spectrum, and near-infrared spectrum from 1.1 to 1.45μm. However, RQ36 is more similar to Pallas in terms of its near-infrared spectrum from 1.6 to 2.3μm. Thus it is possible that B-type asteroids form a spectral continuum and that RQ36 is a transitional object, spectrally intermediate between the two end-members. This is particularly interesting because Asteroid 24 Themis was recently discovered to have H2O ice on the surface (Rivkin, A., Emery, J. [2010]. Nature 464, 1322-1323; Campins, H. et al. [2010a]. Nature 464, 1320-1321).

AB - We present reflectance spectra from 0.4 to 2.4μm of Asteroid (101955) 1999 RQ36, the target of the OSIRIS-REx spacecraft mission. The visible spectral data were obtained at the McDonald Observatory 2.1-m telescope with the ES2 spectrograph. The infrared spectral data were obtained at the NASA Infrared Telescope Facility using the SpeX instrument. The average visible spectrum is combined with the average near-infrared wavelength spectrum to form a composite spectrum. We use three methods to constrain the compositional information in the composite spectrum of Asteroid (101955) 1999 RQ36 (hereafter RQ36). First, we perform a least-squares search for meteorite spectral analogs using 15,000 spectra from the RELAB database. Three most likely meteorite analogs are proposed based on the least-squares search. Next, six spectral parameters are measured for RQ36 and their values are compared with the ranges in parameter values of the carbonaceous chondrite meteorite classes. A most likely meteorite analog group is proposed based on the depth of overlap in parameter values. The results of the least-squares search and the parametric comparisons point to CIs and/or CMs as the most likely meteorite analogs for RQ36, and COs and CHs as the least likely. RQ36 has a spectrally " blue" continuum slope that is also observed in carbonaceous chondrites containing magnetite. We speculate that RQ36 is composed of a " CM1" -like material. Finally, we compare RQ36 to other B-type asteroids measured by Clark et al. (Clark, B.E. et al. [2010]. J. Geophys. Res. 115, E06005). The results of this comparison are inconclusive. RQ36 is comparable to Themis spectral properties in terms of its albedo, visible spectrum, and near-infrared spectrum from 1.1 to 1.45μm. However, RQ36 is more similar to Pallas in terms of its near-infrared spectrum from 1.6 to 2.3μm. Thus it is possible that B-type asteroids form a spectral continuum and that RQ36 is a transitional object, spectrally intermediate between the two end-members. This is particularly interesting because Asteroid 24 Themis was recently discovered to have H2O ice on the surface (Rivkin, A., Emery, J. [2010]. Nature 464, 1322-1323; Campins, H. et al. [2010a]. Nature 464, 1320-1321).

KW - Asteroids

KW - Asteroids, Composition

UR - http://www.scopus.com/inward/record.url?scp=80054916700&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80054916700&partnerID=8YFLogxK

U2 - 10.1016/j.icarus.2011.08.021

DO - 10.1016/j.icarus.2011.08.021

M3 - Article

AN - SCOPUS:80054916700

VL - 216

SP - 462

EP - 475

JO - Icarus

JF - Icarus

SN - 0019-1035

IS - 2

ER -