\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{YORP Effect on Asteroid 162173 Ryugu: Implications for the Dynamical
History}



\author[1]{Masanori Kanamaru}%
\author[2]{Sho Sasaki}%
\author[3]{Tomokatsu Morota}%
\author[3]{Yuichiro Cho}%
\author[4]{Eri Tatsumi}%
\author[5]{Masatoshi Hirabayashi}%
\author[6]{Naru Hirata}%
\author[7]{Hiroki Senshu}%
\author[1]{Yuri Shimaki}%
\author[8]{Naoya Sakatani}%
\author[9]{Satoshi Tanaka}%
\author[10]{Tatsuaki Okada}%
\author[11]{Tomohiro Usui}%
\author[12]{Seiji Sugita}%
\author[13]{Sei-ichiro Watanabe}%
\affil[1]{Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA)}%
\affil[2]{Osaka University}%
\affil[3]{The University of Tokyo}%
\affil[4]{Instituto de Astrofisica de Canarias}%
\affil[5]{Auburn University}%
\affil[6]{University of Aizu}%
\affil[7]{Chiba Institute of Technology}%
\affil[8]{Rikkyo University}%
\affil[9]{JAXA ISAS}%
\affil[10]{JAXA}%
\affil[11]{Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency}%
\affil[12]{University of Tokyo}%
\affil[13]{Nagoya University}%


\vspace{-1em}



  
  \date{May 25, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
Asteroid 162173 (Ryugu) is a carbonaceous asteroid that was visited by
Japan's Hayabusa2 spacecraft in 2018. The formation mechanism of
spinning-top shape of Ryugu is an essential clue to the dynamical
history of the near-Earth asteroid. In this study, we address the
spin-state evolution of Ryugu induced by the
Yarkovsky--O'Keefe--Radzievskii--Paddack (YORP) effect, i.e., the
thermal recoil torque that changes the rotation period and spin-pole
direction.\\
Given the current orbit, spin state, and three-dimensional shape
observed by Hayabusa2, we computed the YORP torque exerted on Ryugu
using a simplified thermal model approximating zero thermal
conductivity. Despite differences in meter-scaled topography, all 20
shape models that we examined indicate that the spin velocity of Ryugu
is currently decreasing at a rate of
(-0.42---6.3)*10\textsuperscript{-6} deg/day\textsuperscript{2}. Our
findings also suggest that the thermal torque on the asteroid is
responsible for maintaining the spin pole upright with respect to the
orbital plane.\\
Therefore, the YORP effect could explain the significant spin-down from
a period of 3.5 h initially to 7.6 h currently. The corresponding time
scale of the rotational deceleration is estimated to be 0.58--8.7
million years, depending on the input shape models. This time scale is
comparable to e.g., the formation period of the largest crater, Urashima
(5--12 Ma) or the western bulge (2--9 Ma) as derived from previous
studies on crater statistics in Ryugu. It is considered that the
rotation of the asteroid started to decelerate in the wake of the major
crater formation or the resurfacing event on the western hemisphere.%
\end{abstract}%



\sloppy




\selectlanguage{english}
\FloatBarrier
\end{document}

