Abstract
We present the study of absolute magnitude (H) and slope parameter (G)
of 170,000 asteroids observed by the Pan-STARRS1 telescope during the
period of 15 months within its 3-year all-sky survey mission. The
exquisite photometry with photometric errors below 0.04 mag and
well-defined filter and photometric system allowed to derive H and G
with statistical and systematic errors. Our new approach lies in the
Monte Carlo technique simulating rotation periods, amplitudes, and
colors, and deriving most-likely H, G and their systematic errors.
Comparison of H_M by Muinonen's phase function (Muinonen et al., 2010)
with the Minor Planet Center database revealed a negative offset of
0.22±0.29 meaning that Pan-STARRS1 asteroids are fainter. We
showed that the absolute magnitude derived by Muinonen's function is
systematically larger on average by 0.14±0.29 and by
0.30±0.16 when assuming fixed slope parameter (G=0.15,
G_{12}=0.53) than Bowell's absolute magnitude (Bowell et al., 1989). We
also derived slope parameters of asteroids of known spectral types and
showed a good agreement with the previous studies within the derived
uncertainties. However, our systematic errors on G and G_{12} are
significantly larger than in previous work, which is caused by poor
temporal and phase coverage of vast majority of the detected asteroids.
This disadvantage will vanish when full survey data will be available
and ongoing extended and enhanced mission will provide new data.
Original language | English |
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Title of host publication | Asteroids, Comets, Meteors: Book of Abstracts, Helsinki, Finland, 2014 |
Editors | Karri Muinonen, Antti Penttila, Michael Granvik, Anne Virkki, Grigori Fedorets, Olli Wilkman, Tomas Kohout |
Publisher | University of Helsinki Press |
Pages | 577 |
Number of pages | 1 |
ISBN (Electronic) | 978-952-10-8962-6 |
Publication status | Published - Jul 2014 |