Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26

Near-Earth object (NEO) 1998 KY _26 is a target of the Hayabusa2# spacecraft, which it will rendezvous with in 2031 July. The asteroid has been noted to rotate rapidly and has a large out-of-plane nongravitational acceleration. We present observations consisting of deep- g - and R -band imaging obta...

Full description

Saved in:
Bibliographic Details
Main Authors: Bryce T. Bolin, Christoffer Fremling, Matthew Belyakov, Jin Beniyama, Marco Delbo, Robert Jedicke, Ian Wong, Laura-May Abron, Keith S. Noll, Andrew W. Stephens
Format: Article
Language:English
Published: IOP Publishing 2025-01-01
Series:The Astronomical Journal
Subjects:
Online Access:https://doi.org/10.3847/1538-3881/adccbe
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850273931751063552
author Bryce T. Bolin
Christoffer Fremling
Matthew Belyakov
Jin Beniyama
Marco Delbo
Robert Jedicke
Ian Wong
Laura-May Abron
Keith S. Noll
Andrew W. Stephens
author_facet Bryce T. Bolin
Christoffer Fremling
Matthew Belyakov
Jin Beniyama
Marco Delbo
Robert Jedicke
Ian Wong
Laura-May Abron
Keith S. Noll
Andrew W. Stephens
author_sort Bryce T. Bolin
collection DOAJ
description Near-Earth object (NEO) 1998 KY _26 is a target of the Hayabusa2# spacecraft, which it will rendezvous with in 2031 July. The asteroid has been noted to rotate rapidly and has a large out-of-plane nongravitational acceleration. We present observations consisting of deep- g - and R -band imaging obtained with the Keck I/Low Resolution Imaging Spectrometer (LRIS) and visible spectroscopy from Gemini North/Gemini Multi-Object Spectrograph (GMOS) taken of 1998 KY _26 on 2024 June 8–9 when the asteroid was ∼0.037 au from the Earth. The asteroid does not show evidence of a dust coma and has a surface brightness profile similar to nearby background stars in the deep images. The spectrum of 1998 KY _26 from the combined LRIS and GMOS observations most closely resembles Xe-type asteroids, possessing a spectral slope of 6.71% ± 0.43% 100 nm ^−1 , and color indices g – r = 0.63 ± 0.03, r – i = 0.15 ± 0.03, i – z = 0.05 ± 0.04, and implies a diameter of ∼10 m. From our deep image stacks, we compute a 3 σ upper limit on the dust production of 1998 KY _26 of <10 ^−5 kg s ^−1 , <10 ^−2 kg s ^−1 , and <10 ^−1 kg s ^−1 assuming μ m, mm, and cm size dust particles. In addition, we compare the orbit of 1998 KY _26 and other known asteroids with large nongravitational parameters to NEO population models and find that the majority, including 1998 KY _26 , likely originated from the inner Main Belt, while the second most numerous group originates from the outer main belt, followed by a third group possibly originating from the Jupiter Family Comet population. Given its inner Main Belt origin, its Xe-type spectrum, and rapid rotation, we hypothesize that the nongravitational acceleration of 1998 KY _26 may be caused by the shedding of large dust grains from its surface due to its rotation rather than H _2 O vapor outgassing.
format Article
id doaj-art-3b5c8b00ea944bebb2a27d33cf72464d
institution OA Journals
issn 1538-3881
language English
publishDate 2025-01-01
publisher IOP Publishing
record_format Article
series The Astronomical Journal
spelling doaj-art-3b5c8b00ea944bebb2a27d33cf72464d2025-08-20T01:51:17ZengIOP PublishingThe Astronomical Journal1538-38812025-01-01169630310.3847/1538-3881/adccbeKeck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26Bryce T. Bolin0https://orcid.org/0000-0002-4950-6323Christoffer Fremling1https://orcid.org/0000-0002-4223-103XMatthew Belyakov2https://orcid.org/0000-0003-4778-6170Jin Beniyama3https://orcid.org/0000-0003-4863-5577Marco Delbo4https://orcid.org/0000-0002-8963-2404Robert Jedicke5https://orcid.org/0000-0001-7830-028XIan Wong6https://orcid.org/0000-0001-9665-8429Laura-May Abron7https://orcid.org/0009-0000-8709-5273Keith S. Noll8https://orcid.org/0000-0002-6013-9384Andrew W. Stephens9https://orcid.org/0000-0002-4434-2307Eureka Scientific , Oakland, CA 94602, USA ; bbolin@eurekasci.comDivision of Physics, Mathematics and Astronomy, California Institute of Technology , Pasadena, CA 91125, USA; Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USADivision of Geological and Planetary Sciences, California Institute of Technology , Pasadena, CA 91125, USAUniversité Côte d’Azur , CNRSgrange, Observatoire de la Côte d’Azur, F 06304, Nice, France; Institute of Astronomy, Graduate School of Science, The University of Tokyo , Mitaka, Tokyo, 181-0015, JapanUniversité Côte d’Azur , CNRSgrange, Observatoire de la Côte d’Azur, F 06304, Nice, France; University of Leicester , School of Physics and Astronomy, Leicester, LE1 7RH, UKInstitute for Astronomy, University of Hawai‘i at Mānoa , Honolulu, HI 96822, USASpace Telescope Science Institute , Baltimore, MD 21218, USAGriffith Observatory , Los Angeles, CA 90027, USAGoddard Space Flight Center , Greenbelt, MD 20771, USAGemini Observatory/NSF NOIRLab , Hilo, HI 96720, USANear-Earth object (NEO) 1998 KY _26 is a target of the Hayabusa2# spacecraft, which it will rendezvous with in 2031 July. The asteroid has been noted to rotate rapidly and has a large out-of-plane nongravitational acceleration. We present observations consisting of deep- g - and R -band imaging obtained with the Keck I/Low Resolution Imaging Spectrometer (LRIS) and visible spectroscopy from Gemini North/Gemini Multi-Object Spectrograph (GMOS) taken of 1998 KY _26 on 2024 June 8–9 when the asteroid was ∼0.037 au from the Earth. The asteroid does not show evidence of a dust coma and has a surface brightness profile similar to nearby background stars in the deep images. The spectrum of 1998 KY _26 from the combined LRIS and GMOS observations most closely resembles Xe-type asteroids, possessing a spectral slope of 6.71% ± 0.43% 100 nm ^−1 , and color indices g – r = 0.63 ± 0.03, r – i = 0.15 ± 0.03, i – z = 0.05 ± 0.04, and implies a diameter of ∼10 m. From our deep image stacks, we compute a 3 σ upper limit on the dust production of 1998 KY _26 of <10 ^−5 kg s ^−1 , <10 ^−2 kg s ^−1 , and <10 ^−1 kg s ^−1 assuming μ m, mm, and cm size dust particles. In addition, we compare the orbit of 1998 KY _26 and other known asteroids with large nongravitational parameters to NEO population models and find that the majority, including 1998 KY _26 , likely originated from the inner Main Belt, while the second most numerous group originates from the outer main belt, followed by a third group possibly originating from the Jupiter Family Comet population. Given its inner Main Belt origin, its Xe-type spectrum, and rapid rotation, we hypothesize that the nongravitational acceleration of 1998 KY _26 may be caused by the shedding of large dust grains from its surface due to its rotation rather than H _2 O vapor outgassing.https://doi.org/10.3847/1538-3881/adccbeNear-Earth objectsAsteroid surfaces
spellingShingle Bryce T. Bolin
Christoffer Fremling
Matthew Belyakov
Jin Beniyama
Marco Delbo
Robert Jedicke
Ian Wong
Laura-May Abron
Keith S. Noll
Andrew W. Stephens
Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
The Astronomical Journal
Near-Earth objects
Asteroid surfaces
title Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
title_full Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
title_fullStr Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
title_full_unstemmed Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
title_short Keck and Gemini Characterization of Hayabusa2# Rendezvous Target 1998 KY26
title_sort keck and gemini characterization of hayabusa2 rendezvous target 1998 ky26
topic Near-Earth objects
Asteroid surfaces
url https://doi.org/10.3847/1538-3881/adccbe
work_keys_str_mv AT brycetbolin keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT christofferfremling keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT matthewbelyakov keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT jinbeniyama keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT marcodelbo keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT robertjedicke keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT ianwong keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT lauramayabron keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT keithsnoll keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26
AT andrewwstephens keckandgeminicharacterizationofhayabusa2rendezvoustarget1998ky26