In the
Tholen classification and in the
SDSS-based taxonomy,
Marghanna is a common, carbonaceous
C-type asteroid, while in the Bus–Binzel
SMASS classification, it is a hydrated C-type (Ch).
Rotation period In May 2011, a rotational
lightcurve of
Marghanna was obtained from
photometric observations by American astronomer
Brian Skiff and collaborators using telescopes at the
Lowell Observatory in Flagstaff, Arizona. The 2019-revised lightcurve analysis gave a well-defined
rotation period of () hours with a small brightness variation of ()
magnitude, indicative of a rather spherical shape (). Lower rated measurements determined a period of 15.95 hours (Rafa Mohamed, 1995), 24 hours (Raymond Poncy, 2005) and hours (Brian Skiff, 2014) with an amplitude of , and magnitude, respectively ().
Diameter and albedo According to the surveys carried out by the
NEOWISE mission of NASA's
Wide-field Infrared Survey Explorer (WISE), the Infrared Astronomical Satellite
IRAS, and the Japanese
Akari satellite,
Marghanna measures (), () and () kilometers in diameter and its surface has an
albedo of (), () and (), respectively. The
Collaborative Asteroid Lightcurve Link derives an albedo of 0.0423 and a diameter of 74.23 kilometers based on an
absolute magnitude of 9.7, while the Cornell Mid-IR Asteroid Spectroscopy (MIDAS) survey determined a diameter of () kilometers and Benoit Carry one of () kilometers. Alternative mean-diameters published by the WISE team include (), (), () and () with a corresponding albedo of (), (), () and (). Two
asteroid occultations on 11 March 2008 and on 4 May 2010, gave a best-fit ellipse dimension of () and (), respectively, each with an intermediate quality rating of 2. These timed observations are taken when the asteroid passes in front of a distant star. == References ==