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NEO Discovery Statistics

NEAR-EARTH ASTEROID DISCOVERY STATISTICS

Some entries in the following charts and tables are dependent upon a diameter that is roughly inferred from the object’s estimated absolute magnitude (H) and its assumed reflectivity, or albedo. The absolute magnitude (H) of a near-Earth asteroid (NEA) is a measure of the object's brightness one astronomical unit from the sun and Earth and at zero phase angle (i.e., the angle between the sun and Earth, as seen from the NEA, is zero). The absolute magnitude (H) for a particular NEA is computed from the observed apparent magnitudes of the object at various times when the phase angles and the distances from the sun and Earth are known. An effective diameter is the diameter of a hypothetical spherical NEA that would provide the same apparent brightness as the observed NEA, whose actual shape is unknown.

Since most NEAs do not have a known reflectivity, or albedo, this albedo must be estimated before the H values, representing intrinsic brightness, can be converted to an approximate diameter. Pravec et al (2012) determined that, for their sample of 583 main-belt asteroids and NEAs, the mean albedos and their standard deviations are 0.057 (±0.013) for the Tholen/Bus/DeMeo C/G/B/F/P/D types and 0.197 (±0.051) for the S/A/L types. Since the albedos for NEAs are most likely to be either approximately 6% for asteroids of the C-type and associated taxonomic classes or 20% for asteroids of the more populous S-type and associated taxonomic classes, we have used an approximate mean value of 14% albedo and an H value of 17.75 to represent a one kilometer spherical NEA. Since the determined H values are uncertain, and likely biased by a few tenths (see Pravec et al., 2012, Icarus) and the single 14% albedo is only a rough mean representing a bimodal albedo distribution, the estimated numbers of one kilometer and larger sized objects in the tables below are very rough. However, these statistics are useful for monitoring the annual NEA discovery progress.

Using near-infrared data provided by the WISE spacecraft in 2010 and early 2011, Mainzer et al (2011) were able to determine diameters and albedos for 250 NEAs with a minimum uncertainty of 10% and 20% respectively. Hence they were able to determine the albedo distribution of these objects with known diameters and this distribution was then used to compute diameters for previously known NEOs with known H values but unknown diameters or albedos. They provided an estimate of 981 (±19) NEAs as the total population of NEAs one kilometer and larger. At the time of their analysis (Spring 2011), they also estimated that 911 (±17) of these large NEAs had already been discovered. While this latter estimate is both higher and more accurate than the estimated numbers given for Spring 2011 in the following tables, this statistical technique cannot be easily employed for day-to-day estimates of the population of NEAs one kilometer and larger. In the following tables, we will continue to use the simpler method described in the previous paragraph.

Mainzer, A. et al. (2011). NEOWISE observations of near-Earth objects: Preliminary Results. Astrophysical Journal. 743:156.
Pravec, P., A.W. Harris, P. Kusnirak, A. Galad, K. Hornoch (2012). Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations. Icarus (submitted 6/2012).
Stuart, J.S. (2003). Observational constraints on the number, albedos, sizes and impact hazards of the near-Earth asteroids. Ph.D. thesis, MIT.

All Asteroids

Table: Number of Near-Earth Asteroid Discoveries at Half-Year Intervals: All Asteroids

Table 1. NEAs Discovered by Site

Half Year
Intervals
LINEAR
(704)
NEAT
(566,608,644)
Spacewatch
(691,291)
LONEOS
(699)
Catalina
(703,E12,G96)
Pan-STARRS
(F51)
NEOWISE
(C51)
OtherCumulative
Total
 1995 (1)001400004334
 1995 (2)001201002349
 1996 (1)151800004377
 1996 (2)051000002394
 1997 (1)321000004413
 1997 (2)149400007447
 1998 (1)4491911007528
 1998 (2)9221562005650
 1999 (1)75012611001755
 1999 (2)8707719003878
 2000 (1)10821421130041040
 2000 (2)15014121700081241
 2001 (1)942872200021394
 2001 (2)18364152000041680
 2002 (1)15857161410061932
 2002 (2)130896700052169
 2003 (1)10230233300092366
 2003 (2)13338332170082606
 2004 (1)167194114250062878
 2004 (2)13772925600063142
 2005 (1)778292211500103403
 2005 (2)5930541919300103768
 2006 (1)44445131950034072
 2006 (2)52175461990054405
 2007 (1)3842072010034678
 2007 (2)7402552660075055
 2008 (1)7404312810055459
 2008 (2)66043028000115859
 2009 (1)51032026000186220
 2009 (2)58031031500176641
 2010 (1)29021025708797044
 2010 (2)7502203461737147555
 2011 (1)410170328683128024
 2011 (2)2901502521040238447
 2012 (1)260130352120078965
 2012 (2)2901302771310269441
 2013 (1)301302881510189914
 2013 (2)0012031520812910479
 2014 (1)00803322411614611222
 2014 (2)0080285380243811957
 2015 (1)*00001031624612232
* Incomplete half-year (based on discovery data through 2015-Mar-05 06:05 local)

Large Asteroids

Table: Number of Near-Earth Asteroid Discoveries at Half-Year Intervals: Large Asteroids

Table 2. Large NEAs Discovered by Site

Half Year
Intervals
LINEAR
(704)
NEAT
(566,608,644)
Spacewatch
(691,291)
LONEOS
(699)
Catalina
(703,E12,G96)
Pan-STARRS
(F51)
NEOWISE
(C51)
OtherCumulative
Total
 1995 (1)00300002176
 1995 (2)00400001181
 1996 (1)02200000185
 1996 (2)02000000187
 1997 (1)01300001192
 1997 (2)23100002200
 1998 (1)74210002216
 1998 (2)242130003249
 1999 (1)160244000275
 1999 (2)230112002304
 2000 (1)332114001346
 2000 (2)372350004397
 2001 (1)238040000432
 2001 (2)225040001464
 2002 (1)294230001503
 2002 (2)1910010001534
 2003 (1)143260002561
 2003 (2)175142001591
 2004 (1)155123001618
 2004 (2)910112000641
 2005 (1)100219001664
 2005 (2)645010001690
 2006 (1)30219000705
 2006 (2)102012000720
 2007 (1)20309001735
 2007 (2)50107000748
 2008 (1)20109000760
 2008 (2)30104000768
 2009 (1)10009000778
 2009 (2)60006002792
 2010 (1)00004030799
 2010 (2)10001030804
 2011 (1)20005100812
 2011 (2)00106300822
 2012 (1)00009100832
 2012 (2)10005200840
 2013 (1)00004000844
 2013 (2)00003201850
 2014 (1)00002420858
 2014 (2)00001310863
 2015 (1)*00000300866
* Incomplete half-year (based on discovery data through 2015-Mar-05 06:05 local)
NOTE: In the year 2010, the "Other" site category was exclusively WISE.
A separate table of WISE discoveries is
available.

Data compiled by Alan Chamberlin.

NUMBER OF NEOS
With over 90% of the near-Earth objects larger than one kilometer already discovered, the NEO Program is now focusing on finding 90% of the NEO population larger than 140 meters. A separate table containing WISE discoveries for NEAs and comets is available.

The chart below shows the cumulative total known near-Earth asteroids versus time. The blue area shows all near-Earth asteroids while the red area shows only large near-Earth asteroids (those with diameters roughly one kilometer and larger).
Table: Number of Known Near-Earth Asteroids Over Time
(click on the chart above for a larger version)

The chart below shows the total known near-Earth asteroids per size bin. Diameters are estimated using an assumed average albedo for NEAs. The first size bin represents NEAs smaller than 30m in diameter. The second represents NEAs with diameters from 30m to 100m, and so on.
Known Near-Earth Asteroids by Size Bin
Data shown in the chart above represent known NEAs as of the date shown in the bottom-right corner of the chart.

The table below shows the total number of NEOs known at selected dates. The most recent date at the top of the table is generally not the date the table was updated, but rather the discovery date of the most recently discovered NEO. Numbers for large asteroids (PHA-KM and NEA-KM) are rough estimates (see introductory note above). This table is updated daily using discovery data published by the Minor Planet Center.

----------------------------------------------------------------------------
   Date      NEC  Atira  Aten Apollo  Amor  PHA-KM  PHA  NEA-KM  NEA    NEO
----------  ----  ----- ----- ------ -----  ------ ----  ------ -----  -----
2015-02-27    96     15   905   6609  4703     153 1558     866 12232  12328
2015-02-01    96     14   898   6529  4667     153 1546     866 12108  12204
2015-01-01    95     14   889   6450  4604     153 1533     863 11957  12052
2014-12-01    95     14   880   6386  4567     153 1524     861 11847  11942
2014-11-01    95     14   874   6312  4504     153 1515     858 11704  11799
2014-10-01    94     14   867   6222  4441     153 1510     858 11544  11638
2014-09-01    94     14   861   6169  4386     153 1504     858 11430  11524
2014-08-01    94     14   856   6116  4313     153 1495     858 11299  11393
2014-07-01    94     14   854   6073  4281     153 1485     858 11222  11316
2014-06-01    94     14   845   6036  4224     152 1477     854 11119  11213
2014-05-01    94     14   838   5969  4177     152 1465     852 10998  11092
2014-04-01    94     14   826   5853  4068     152 1457     851 10761  10855
2014-03-01    94     13   819   5797  4041     152 1452     851 10670  10764
2014-02-01    94     13   811   5752  4003     152 1445     851 10579  10673
2014-01-01    94     13   804   5699  3963     152 1441     850 10479  10573
2013-12-01    94     13   799   5644  3937     152 1437     850 10393  10487
2013-11-01    94     13   798   5573  3910     152 1429     850 10294  10388
2013-10-01    94     12   786   5514  3848     151 1421     846 10160  10254
2013-09-01    94     12   780   5457  3793     151 1417     845 10042  10136
2013-08-01    94     12   778   5426  3756     151 1411     845  9972  10066
2013-07-01    94     12   773   5398  3731     151 1404     844  9914  10008
2013-06-01    94     12   770   5368  3713     151 1398     842  9863   9957
2013-05-01    94     11   765   5328  3693     151 1391     842  9797   9891
2013-04-01    94     11   760   5287  3662     151 1382     841  9720   9814
2013-03-01    94     11   755   5239  3633     151 1373     841  9638   9732
2013-02-01    93     11   750   5200  3606     151 1369     841  9567   9660
2013-01-01    93     11   743   5119  3568     151 1355     840  9441   9534
2012-12-01    93     11   735   5066  3537     151 1344     840  9349   9442
2012-11-01    92     10   727   5012  3500     151 1335     837  9249   9341
2012-10-01    92     10   721   4937  3444     151 1324     835  9112   9204
2012-09-01    92     10   717   4904  3414     151 1321     834  9045   9137
2012-08-01    92     10   712   4879  3380     151 1316     833  8981   9073
2012-07-01    91     10   711   4873  3371     151 1312     832  8965   9056
2012-06-01    91     10   706   4847  3348     151 1303     829  8911   9002
2012-05-01    91     10   704   4814  3324     151 1298     826  8852   8943
2012-04-01    91     10   702   4763  3297     151 1292     825  8772   8863
2012-03-01    91     10   696   4683  3270     151 1286     823  8659   8750
2012-02-01    91     10   686   4636  3229     151 1280     823  8561   8652
2012-01-01    91     10   676   4567  3194     151 1272     822  8447   8538
2011-12-01    91     10   672   4535  3169     151 1265     818  8386   8477
2011-11-01    91     10   669   4494  3135     149 1255     815  8308   8399
2011-10-01    91     10   662   4432  3090     148 1244     814  8194   8285
2011-09-01    90     10   661   4397  3037     148 1238     813  8105   8195
2011-08-01    90     10   661   4381  3011     148 1235     812  8063   8153
2011-07-01    89     10   659   4368  2987     148 1231     812  8024   8113
2011-06-01    89     10   659   4351  2962     148 1225     811  7982   8071
2011-05-01    89     10   656   4325  2939     148 1217     809  7930   8019
2011-04-01    89     10   645   4276  2910     148 1210     807  7841   7930
2011-03-01    89     10   634   4213  2886     148 1201     805  7743   7832
2011-02-01    89     10   624   4167  2868     148 1190     805  7669   7758
2011-01-01    89     10   618   4092  2835     148 1174     804  7555   7644
2010-12-01    89      9   609   4037  2804     148 1165     804  7459   7548
2010-11-01    89      9   598   3968  2758     148 1159     804  7333   7422
2010-10-01    89      9   588   3912  2719     148 1145     804  7228   7317
2010-09-01    89      9   582   3865  2654     148 1140     803  7110   7199
2010-08-01    89      9   579   3851  2643     148 1137     800  7082   7171
2010-07-01    89      9   574   3829  2632     148 1135     799  7044   7133
2010-06-01    88      9   568   3798  2610     148 1127     798  6985   7073
2010-05-01    87      9   560   3754  2591     147 1115     796  6914   7001
2010-04-01    87      9   552   3708  2574     147 1109     796  6843   6930
2010-03-01    87      9   544   3671  2549     146 1100     795  6773   6860
2010-02-01    87      9   540   3617  2524     146 1088     794  6690   6777
2010-01-01    87      9   535   3591  2506     146 1085     792  6641   6728
2009-12-01    87      9   531   3570  2496     146 1080     790  6606   6693
2009-11-01    86      9   520   3494  2467     146 1072     787  6490   6576
2009-10-01    86      9   511   3439  2434     146 1068     785  6393   6479
2009-09-01    86      9   506   3386  2387     146 1059     783  6288   6374
2009-08-01    86      9   504   3366  2360     146 1057     782  6239   6325
2009-07-01    86      9   504   3356  2351     145 1055     778  6220   6306
2009-06-01    85      9   501   3345  2340     144 1052     777  6195   6280
2009-05-01    85      9   499   3318  2326     144 1043     776  6152   6237
2009-04-01    85      9   496   3286  2312     144 1039     773  6103   6188
2009-03-01    85      9   491   3225  2293     144 1027     773  6018   6103
2009-02-01    85      9   487   3166  2267     143 1015     770  5929   6014
2009-01-01    85      9   481   3122  2247     143 1006     768  5859   5944
2008-12-01    84      9   480   3080  2218     143  996     767  5787   5871
2008-11-01    84      9   474   3032  2196     143  988     765  5711   5795
2008-10-01    84      8   467   2970  2145     142  978     764  5590   5674
2008-09-01    83      8   464   2939  2110     142  968     763  5521   5604
2008-08-01    83      8   461   2925  2096     142  963     762  5490   5573
2008-07-01    83      8   459   2908  2084     142  954     760  5459   5542
2008-06-01    83      8   455   2897  2076     142  951     759  5436   5519
2008-05-01    83      8   451   2867  2058     142  945     758  5384   5467
2008-04-01    83      8   449   2820  2029     142  942     757  5306   5389
2008-03-01    83      7   440   2752  2004     141  932     750  5203   5286
2008-02-01    83      7   428   2692  1974     140  918     748  5101   5184
2008-01-01    83      7   426   2665  1957     140  910     748  5055   5138
2007-12-01    83      7   423   2630  1940     140  899     745  5000   5083
2007-11-01    83      7   411   2572  1904     140  889     741  4894   4977
2007-10-01    82      7   397   2523  1862     140  878     740  4789   4871
2007-09-01    82      7   390   2485  1830     139  871     739  4712   4794
2007-08-01    82      7   388   2474  1820     138  866     735  4689   4771
2007-07-01    82      7   388   2470  1813     138  865     735  4678   4760
2007-06-01    82      7   383   2448  1804     137  856     733  4642   4724
2007-05-01    82      7   382   2435  1793     137  852     731  4617   4699
2007-04-01    82      7   381   2409  1776     137  848     727  4573   4655
2007-03-01    82      6   375   2369  1753     137  841     725  4503   4585
2007-02-01    82      6   367   2336  1737     136  833     721  4446   4528
2007-01-01    82      6   359   2316  1724     136  824     720  4405   4487
2006-12-01    81      6   354   2290  1706     136  821     718  4356   4437
2006-11-01    81      5   344   2241  1683     135  809     712  4273   4354
2006-10-01    79      5   337   2211  1651     135  799     710  4204   4283
2006-09-01    79      5   330   2174  1624     134  790     706  4133   4212
2006-08-01    79      5   328   2157  1611     134  785     706  4101   4180
2006-07-01    79      5   327   2146  1594     134  783     705  4072   4151
2006-06-01    79      5   326   2135  1581     134  780     705  4047   4126
2006-05-01    79      5   325   2107  1554     134  770     701  3991   4070
2006-04-01    78      5   321   2080  1539     134  761     699  3945   4023
2006-03-01    78      5   319   2065  1520     134  760     698  3909   3987
2006-02-01    78      5   316   2030  1503     134  752     695  3854   3932
2006-01-01    78      5   312   1975  1476     133  743     690  3768   3846
2005-12-01    78      5   302   1943  1455     132  732     687  3705   3783
2005-11-01    77      5   297   1901  1429     131  722     682  3632   3709
2005-10-01    76      4   289   1845  1389     130  710     671  3527   3603
2005-09-01    76      4   286   1811  1370     130  705     668  3471   3547
2005-08-01    76      4   283   1797  1354     130  699     667  3438   3514
2005-07-01    76      4   279   1778  1342     129  692     664  3403   3479
2005-06-01    76      4   275   1763  1322     129  688     659  3364   3440
2005-05-01    75      4   274   1746  1308     127  682     656  3332   3407
2005-04-01    75      4   268   1721  1290     125  669     652  3283   3358
2005-03-01    75      4   263   1681  1264     124  659     648  3212   3287
2005-02-01    75      4   262   1658  1256     123  655     645  3180   3255
2005-01-01    75      4   258   1634  1246     123  648     641  3142   3217
2004-12-01    74      3   249   1602  1225     123  640     633  3079   3153
2004-11-01    74      3   245   1582  1219     122  631     628  3049   3123
2004-10-01    73      3   238   1554  1211     121  620     626  3006   3079
2004-09-01    72      3   230   1516  1186     121  612     625  2935   3007
2004-08-01    72      3   226   1496  1164     120  605     621  2889   2961
2004-07-01    72      3   226   1489  1160     118  602     618  2878   2950
2004-06-01    72      3   223   1459  1147     117  591     615  2832   2904
2004-05-01    72      2   218   1440  1132     117  585     611  2792   2864
2004-04-01    72      2   215   1410  1120     113  575     604  2747   2819
2004-03-01    72      2   206   1374  1102     113  568     595  2684   2756
2004-02-01    71      2   204   1359  1095     112  563     594  2660   2731
2004-01-01    71      2   202   1325  1077     110  553     591  2606   2677
2003-12-01    71      2   196   1293  1065     107  540     583  2556   2627
2003-11-01    71      2   193   1272  1052     107  533     577  2519   2590
2003-10-01    70      2   188   1245  1030     107  524     575  2465   2535
2003-09-01    70      2   185   1225   996     105  515     568  2408   2478
2003-08-01    70      2   185   1213   983     102  510     564  2383   2453
2003-07-01    69      2   184   1206   974     102  507     561  2366   2435
2003-06-01    69      2   182   1190   962     102  502     555  2336   2405
2003-05-01    67      2   180   1176   956     101  500     553  2314   2381
2003-04-01    67      2   175   1156   945     100  492     547  2278   2345
2003-03-01    67      2   170   1137   934     100  485     543  2243   2310
2003-02-01    67      1   169   1117   928     100  479     539  2215   2282
2003-01-01    67      1   167   1090   911      99  469     534  2169   2236
2002-12-01    67      1   163   1063   891      99  467     532  2118   2185
2002-11-01    67      1   160   1048   874      98  461     528  2083   2150
2002-10-01    66      1   158   1024   851      97  455     520  2034   2100
2002-09-01    64      1   155   1004   831      96  449     511  1991   2055
2002-08-01    64      1   154    988   808      94  438     508  1951   2015
2002-07-01    63      1   152    978   801      93  431     503  1932   1995
2002-06-01    63      1   148    960   792      91  422     497  1901   1964
2002-05-01    63      1   144    942   781      90  413     486  1868   1931
2002-04-01    63      1   142    924   768      90  406     484  1835   1898
2002-03-01    62      1   136    897   754      89  396     481  1788   1850
2002-02-01    62      1   131    874   738      88  387     471  1744   1806
2002-01-01    62      1   124    840   715      88  374     464  1680   1742
2001-12-01    62      1   121    804   696      84  360     455  1622   1684
2001-11-01    60      1   120    776   681      83  353     451  1578   1638
2001-10-01    60      1   114    751   657      82  344     447  1523   1583
2001-09-01    60      1   110    722   623      81  333     436  1456   1516
2001-08-01    59      1   109    700   603      81  327     433  1413   1472
2001-07-01    58      1   108    695   590      81  326     432  1394   1452
2001-06-01    57      1   108    685   580      79  323     425  1374   1431
2001-05-01    56      1   107    673   569      77  316     417  1350   1406
2001-04-01    56      1   105    661   560      76  307     413  1327   1383
2001-03-01    56      1   101    646   546      74  298     406  1294   1350
2001-02-01    56      1    98    635   535      73  295     401  1269   1325
2001-01-01    56      1    94    620   526      73  292     397  1241   1297
2000-12-01    56      1    93    606   514      72  286     390  1214   1270
2000-11-01    56      1    90    582   497      71  283     381  1170   1226
2000-10-01    56      1    87    572   483      71  279     374  1143   1199
2000-09-01    56      1    81    554   457      70  272     366  1093   1149
2000-08-01    56      1    79    536   441      68  263     357  1057   1113
2000-07-01    56      1    77    531   431      66  260     346  1040   1096
2000-06-01    56      1    76    526   425      65  256     343  1028   1084
2000-05-01    56      1    76    513   411      65  251     335  1001   1057
2000-04-01    55      1    73    498   398      64  245     328   970   1025
2000-03-01    55      1    64    482   387      62  233     316   934    989
2000-02-01    55      1    62    465   376      61  222     309   904    959
2000-01-01    55      1    57    451   369      61  216     304   878    933
1999-12-01    54      1    56    441   360      59  208     297   858    912
1999-11-01    54      1    54    428   346      59  204     287   829    883
1999-10-01    54      1    54    412   332      58  199     283   799    853
1999-09-01    52      1    54    396   316      56  192     279   767    819
1999-08-01    52      1    54    396   314      56  192     279   765    817
1999-07-01    52      1    54    391   309      55  190     275   755    807
1999-06-01    52      1    51    384   299      55  186     272   735    787
1999-05-01    51      1    49    372   293      51  178     262   715    766
1999-04-01    51      1    48    359   286      50  174     255   694    745
1999-03-01    51      1    47    349   281      50  172     254   678    729
1999-02-01    51      1    47    339   276      50  169     251   663    714
1999-01-01    51      1    45    334   270      50  166     249   650    701
1998-12-01    51      1    41    324   261      50  162     240   627    678
1998-11-01    51      1    38    310   252      48  154     235   601    652
1998-10-01    51      1    36    306   245      48  152     231   588    639
1998-09-01    51      1    29    293   232      47  140     225   555    606
1998-08-01    51      1    29    283   221      45  133     219   534    585
1998-07-01    51      1    29    279   219      43  129     216   528    579
1998-06-01    51      1    29    273   212      42  127     213   515    566
1998-05-01    51      1    29    264   206      42  124     209   500    551
1998-04-01    51      1    27    256   197      42  117     208   481    532
1998-03-01    51      1    27    244   189      42  112     204   461    512
1998-02-01    51      0    26    240   189      41  110     203   455    506
1998-01-01    51      0    26    235   186      41  108     200   447    498
1997-01-01    51      0    22    206   166      39   97     187   394    445
1996-01-01    51      0    20    178   151      37   86     181   349    400
1995-01-01    51      0    19    163   134      36   83     171   316    367
1994-01-01    49      0    15    140   114      32   70     153   269    318
1993-01-01    49      0    13    117    98      30   64     139   228    277
1992-01-01    49      0    11    103    84      28   61     122   198    247
1991-01-01    47      0     9     76    73      23   49     104   158    205
1990-01-01    47      0     8     63    62      20   42      89   133    180
1980-01-01    43      0     3     27    22      12   17      44    52     95
1970-01-01    41      0     0     13    14       8   10      24    27     68
1960-01-01    40      0     0     10    10       7    8      18    20     60
1950-01-01    40      0     0      7     6       4    5      12    13     53
1940-01-01    35      0     0      3     6       2    3       8     9     44
1930-01-01    33      0     0      0     5       0    0       5     5     38
1920-01-01    31      0     0      0     3       0    0       3     3     34
1910-01-01    29      0     0      0     1       0    0       1     1     30
1900-01-01    27      0     0      0     1       0    0       1     1     28

Note: "NEC" are Near-Earth comets. "PHA-KM" and "NEA-KM" are PHAs and NEAs with diameters roughly one kilometer and larger. Other definitions, such as Apollo, are on the NEO groups page.

Data compiled by Alan Chamberlin.

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