Editing Jupiter trojan (section)

=== Rotation ===
The rotational properties of Jupiter trojans are not well known. Analysis of the rotational [[light curve]]s of 72 Jupiter trojans gave an average rotational period of about 11.2&nbsp;hours, whereas the average period of the control sample of asteroids in the asteroid belt was 10.6&nbsp;hours.<ref name=Barucci2002/> The distribution of the rotational periods of Jupiter trojans appeared to be well approximated by a [[Maxwell distribution|Maxwellian function]],<ref group="Note">The Maxwellian function is <math>F=\begin{smallmatrix}\frac{1}{\sqrt{2\pi}\sigma}P^2\exp(-(P-P_0)^2/\sigma^2)\end{smallmatrix}</math>, where <math>P_0</math> is the average rotational period, <math>\sigma</math> is the [[Statistical dispersion|dispersion]] of periods.</ref> whereas the distribution for main-belt asteroids was found to be non-Maxwellian, with a deficit of periods in the range 8–10&nbsp;hours.<ref name=Barucci2002/> The Maxwellian distribution of the rotational periods of Jupiter trojans may indicate that they have undergone a stronger collisional evolution compared to the asteroid belt.<ref name=Barucci2002/>

In 2008 a team from [[Calvin College]] examined the [[light curve]]s of a debiased sample of ten Jupiter trojans, and found a [[median]] spin period of 18.9 hours. This value was significantly higher than that for main-belt asteroids of similar size (11.5 hours). The difference could mean that the Jupiter trojans possess a lower average density, which may imply that they formed in the [[Kuiper belt]] (see below).<ref>{{cite journal|last1=Molnar|first1=Lawrence A.|last2=Haegert|first2=Melissa J.|last3=Hoogeboom|first3=Kathleen M.|date=April 2008|title=Lightcurve Analysis of an Unbiased Sample of Trojan Asteroids|journal=The Minor Planet Bulletin|publisher=Association of Lunar and Planetary Observers|volume=35|issue=2|pages=82–84|oclc=85447686|bibcode=2008MPBu...35...82M}}</ref>