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The Mission Accessible Near-Earth Objects Survey (MANOS): first photometric results

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 نشر من قبل Audrey Thirouin
 تاريخ النشر 2016
  مجال البحث فيزياء
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The Mission Accessible Near-Earth Objects Survey (MANOS) aims to physically characterize sub-km Near-Earth Objects (NEOs). We report first photometric results from the survey which began in August, 2013. Photometric observations were performed using 1 m to 4 m class telescopes around the world. We present rotational periods and lightcurve amplitudes for 86 sub-km NEOs, though in some cases, only lower limits are provided. Our main goal is to obtain lightcurves for small NEOs (typically, sub-km objects) and estimate their rotational periods, lightcurve amplitudes, and shapes. These properties are used for statistical study to constrain overall properties of the NEO population. A weak correlation seems to indicate that smaller objects are more spherical than the larger ones. We also report 7 NEOs that are fully characterized (lightcurve and visible spectra) as the most suitable candidates for a future human or robotic mission. Viable mission targets are objects fully characterized, with a Delta_v(NHATS) <12 km s^-1, and a rotational period P>1h. Assuming a similar rate of object characterization as reported in this paper, approximately 1,230 NEOs need to be characterized in order to find 100 viable mission targets.



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