NEOWISE OBSERVATIONS OF NEAR-EARTH OBJECTS: PRELIMINARY RESULTS

Journal Article · Tue Dec 20 00:00:00 EST 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/743/2/156· OSTI ID:22004400

Mainzer, A; Bauer, J; Masiero, J; Eisenhardt, P ^[1]; Grav, T; Mo, W ^[2]; McMillan, R S ^[3]; Cutri, R M ^[4]; Walker, R ^[5]; Wright, E ^[6]; Tholen, D J; Jedicke, R; Denneau, L ^[7]; Spahr, T ^[8]; DeBaun, E ^[9]; Elsbury, D ^[10]; Gautier, T ^[11]; Gomillion, S ^[12]; Hand, E ^[13]; Watkins, J ^[14] ; others, and

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1. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)
2. Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD (United States)
3. Lunar and Planetary Laboratory, University of Arizona, 1629 East University Blvd., Tucson, AZ 85721-0092 (United States)
4. Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)
5. Monterey Institute for Research in Astronomy, Monterey, CA (United States)
6. Department of Physics and Astronomy, UCLA, P.O. Box 91547, Los Angeles, CA 90095-1547 (United States)
7. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI (United States)
8. Minor Planet Center, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
9. Department of Physics and Astronomy, Dartmouth University, Hanover, NH 03755 (United States)
10. University of California Santa Barbara, Broida Hall, Santa Barbara, CA 93103 (United States)
11. Cornell University, Ithaca, NY 14853 (United States)
12. Department of Engineering Physics, Embry-Riddle Aeronautical University, 600 S. Clyde Morris Boulevard, Daytona Beach, FL 32114 (United States)
13. Department of Mechanical Engineering, University of Missouri-Kansas City, Kansas City, MO 64110 (United States)
14. Department of Earth and Space Sciences, UCLA, 595 Charles Young Drive East, Box 951567, Los Angeles, CA 90095 (United States)

With the NEOWISE portion of the Wide-field Infrared Survey Explorer (WISE) project, we have carried out a highly uniform survey of the near-Earth object (NEO) population at thermal infrared wavelengths ranging from 3 to 22 {mu}m, allowing us to refine estimates of their numbers, sizes, and albedos. The NEOWISE survey detected NEOs the same way whether they were previously known or not, subject to the availability of ground-based follow-up observations, resulting in the discovery of more than 130 new NEOs. The survey's uniform sensitivity, observing cadence, and image quality have permitted extrapolation of the 428 near-Earth asteroids (NEAs) detected by NEOWISE during the fully cryogenic portion of the WISE mission to the larger population. We find that there are 981 {+-} 19 NEAs larger than 1 km and 20,500 {+-} 3000 NEAs larger than 100 m. We show that the Spaceguard goal of detecting 90% of all 1 km NEAs has been met, and that the cumulative size distribution is best represented by a broken power law with a slope of 1.32 {+-} 0.14 below 1.5 km. This power-law slope produces {approx}13, 200 {+-} 1900 NEAs with D > 140 m. Although previous studies predict another break in the cumulative size distribution below D {approx} 50-100 m, resulting in an increase in the number of NEOs in this size range and smaller, we did not detect enough objects to comment on this increase. The overall number for the NEA population between 100 and 1000 m is lower than previous estimates. The numbers of near-Earth comets and potentially hazardous NEOs will be the subject of future work.

• OSTI ID: 22004400
• Journal Information: Astrophysical Journal, Vol. 743, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ALBEDO
ASTEROIDS
COMETS
EXTRAPOLATION
INFRARED SURVEYS
PLANETS
SATELLITES