in october 2005, a rotational lightcurve of "erna" was obtained from photometric observations by french and italian astronomers raymond poncy (), roberto crippa (), federico manzini and silvano casulli. lightcurve analysis gave a well-defined rotation period of 8.7893 hours with a brightness variation of 0.35 magnitude (). another lightcurve from the palomar transient factory in november 2010 gave a similar period of 8.790 hours with an amplitude of 0.35 magnitude ().