The Size Distribution of Near-Earth Objects Larger Than 10 m

We analyzed data from the first year of a survey for Near-Earth Objects (NEOs) that we are carrying out with the Dark Energy Camera (DECam) on the 4 m Blanco telescope at the Cerro Tololo Inter-American Observatory. We implanted synthetic NEOs into the data stream to derive our nightly detection efficiency as a function of magnitude and rate of motion. Using these measured efficiencies and the solar system absolute magnitudes derived by the Minor Planet Center for the 1377 measurements of 235 unique NEOs detected, we directly derive, for the first time from a single observational data set, the NEO size distribution from 1 km down to 10 m. We find that there are NEOs larger than 10 m. This result implies a factor of 10 fewer small NEOs than some previous results, though our derived size distribution is in good agreement with several other estimates.

[1]  R. Wainscoat,et al.  The size-frequency distribution of H > 13 NEOs and ARM target candidates detected by Pan-STARRS1 , 2016, 1611.03095.

[2]  P. Tricarico.  The near-Earth asteroid population from two decades of observations , 2016, 1604.06328.

[3]  T. Grav,et al.  INITIAL PERFORMANCE OF THE NEOWISE REACTIVATION MISSION , 2014, 1406.6025.

[4]  G. Fazio,et al.  PHYSICAL PROPERTIES OF NEAR-EARTH ASTEROID 2011 MD , 2014, 1406.5253.

[5]  R. Keppens,et al.  THE DYNAMICS OF FUNNEL PROMINENCES , 2014, 1405.3419.

[6]  D. Trilling,et al.  CONSTRAINING THE PHYSICAL PROPERTIES OF NEAR-EARTH OBJECT 2009 BD , 2014, 1403.7699.

[7]  J. Borovička,et al.  A 500-kiloton airburst over Chelyabinsk and an enhanced hazard from small impactors , 2013, Nature.

[8]  P. A. Price,et al.  THE PAN-STARRS 1 PHOTOMETRIC REFERENCE LADDER, RELEASE 12.01 , 2013, 1303.3634.

[9]  B. Gladman,et al.  The orbital distribution of Near-Earth Objects inside Earth's orbit , 2012 .

[10]  E. L. Wright,et al.  NEOWISE STUDIES OF SPECTROPHOTOMETRICALLY CLASSIFIED ASTEROIDS: PRELIMINARY RESULTS , 2011, 1109.6407.

[11]  K. Honscheid,et al.  The Dark Energy Camera (DECam) , 2008, Astronomical Telescopes + Instrumentation.

[12]  J. Munn,et al.  The USNO-B Catalog , 2002, astro-ph/0210694.

[13]  Stephanie C. Werner,et al.  The Near-Earth Asteroid Size–Frequency Distribution: A Snapshot of the Lunar Impactor Size–Frequency Distribution , 2002 .

[14]  A. Harris,et al.  The population of near-Earth asteroids , 2000 .

[15]  D. Rabinowitz,et al.  A reduced estimate of the number of kilometre-sized near-Earth asteroids , 2000, Nature.

[16]  David L. Rabinowitz,et al.  The size distribution of the earth-approaching asteroids , 1993 .

[17]  Maarten Schmidt,et al.  Space Distribution and Luminosity Functions of Quasi-Stellar Radio Sources , 1968 .