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Legend - object IDs plus links to more info

Data compiled at 2113 UTC on 24 Feb. 2017 for 29 known objects during a period of seven days from 21 to 27 Feb. 2017. White type highlights objects with just announced discovery, and orange is for objects with a new JPL orbit solution (usually from new observation).

Chart
ID

Full ID
Period
Closest
Passage
Uncertainty

Status
AG52017 AG5123.47 LD  departed
BG302017 BG3011.52 LD  departed
BW2017 BW6.35 LDoutbound
BY2017 BY55.63 LD  departed
BY932017 BY932.37 LDoutbound
CF322017 CF3210.03 LD  departed
CP12017 CP13.58 LDpassing
CP322017 CP3220.45 LD  departed
CR52017 CR524.62 LD  departed
CS2017 CS190.6 LD+/- 22 minutesapproaching
CX312017 CX3128.00 LD  departed
DB2017 DB1.91 LDoutbound
DF2017 DF2.84 LDoutbound
DG162017 DG160.36 LDoutbound intruder
DH162017 DH167.28 LD+/- 2 minutes  departed
DJ162017 DJ164.70 LD+/- one minuteapproaching
DK342017 DK3415.70 LD  departed
DR322012 DR3210.7 LD+/- 4.1333 hoursapproaching
DR342017 DR340.58 LDinbound intruder
DS152017 DS1531.19 LD  departed
DS342017 DS347.12 LD+/- 2 minutesapproaching
DT342017 DT342.44 LDpassing
DU342017 DU349.99 LDpassing
DV152017 DV158.76 LDoutbound
DX342017 DX3414.2 LD+/- 1.2500 hours  departed
FE902001 FE90289.0 LD  distant
JO252014 JO25399.00 LDapproaching
SL361998 SL3656.90 LDapproaching
TC252015 TC2520.57 LD+/- 6 minutesapproaching
DateTfc.Time
21 Feb. '17Rept. Line
22 Feb. '17Rept. Line
23 Feb. '17Rept. Line
24 Feb. '17Rept. Line
25 Feb. '17Rept. Line
26 Feb. '17 Line
27 Feb. '17 Line

Object Details - Skychart objects presented in reverse designation order, newest first
  ("designation assigned to" indicates unofficial discovery credit)

2017 DX34   -     departed
Approximate diameter29 meters (H=25.331)
Closest Earth approach5.05 LD at 0834 UT on 10 Feb. 2017 - Note: JPL reports an approach uncertainty of +/- 1.2500 hours
Inside ten LD of Earth3 to 17 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 24 Feb. 2017 UTC
based on 16 observations spanning one day
Optical observation  
  • reported from 4 observing codes during 1.2454 days: 300, 568, F51, I52
  • designation assigned to Pan-STARRS 1 observation at 1404 UT 22 Feb. 2017
  • last observed at 1958 UT on 23 Feb. 2017 by Bisei Spaceguard Center
Links  
2017 DU34   -   passing
Approximate diameter15 meters (H=26.742)
Closest Earth approach9.99 LD at 0150 UT on 24 Feb. 2017
Inside ten LD of Earth23 to 24 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 24 Feb. 2017 UTC
based on 18 observations spanning one day
Optical observation  
  • reported from 5 observing codes during 1.5213 days: F51, G96, H01, I52, J95
  • designation assigned to Mt. Lemmon Survey observation at 0805 UT 22 Feb. 2017
  • last observed at 2035 UT on 23 Feb. 2017 by Great Shefford Obs.
Links  
2017 DT34   -   passing
Approximate diameter10 meters (H=27.674)
Closest Earth approach2.44 LD at 0332 UT on 24 Feb. 2017
Inside ten LD of Earth20 to 28 Feb. 2017
Data based onJPL SSD orbit solution #2 downloaded from JPL on 24 Feb. 2017 UTC
based on 39 observations spanning 6 days
Optical observation  
  • reported from 8 observing codes during 5.8238 days: 474, 958, F51, G96, H01, I52, J95, Q62
  • first observed at 0659 UT on 18 Feb. 2017 by Pan-STARRS 1
  • designation assigned to Mt. Lemmon Survey observation at 0738 UT 22 Feb. 2017
  • last observed at 0246 UT on 24 Feb. 2017 by Great Shefford Obs.
Links  
2017 DS34   -   approaching
Approximate diameter24 meters (H=25.739)
Closest Earth approach7.12 LD at 1948 UT on 27 Feb. 2017 - Note: JPL reports an approach uncertainty of +/- 2 minutes
Inside ten LD of Earth26 Feb. until 1 March 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 24 Feb. 2017 UTC
based on 26 observations spanning 2 days
Optical observation  
  • reported from 4 observing codes during 1.7162 days: 474, G96, I52, J95
  • first observed at 0654 UT on 22 Feb. 2017 by the Mt. Lemmon Survey
  • designation assigned to Mt. Lemmon Survey observation at 0735 UT 22 Feb. 2017
  • last observed at 0005 UT on 24 Feb. 2017 by Great Shefford Obs.
Links  
2017 DR34   -   inbound intruder
Approximate diameter5 meters (H=29.103)
Closest Earth approach0.58 LD at 0451 UT on 25 Feb. 2017
Inside Earth-Moon system2111 on 24 Feb. until 1231 UT on 25 Feb. 2017
Inside Earth SOI24 to 26 Feb. 2017
Inside ten LD of Earth21 Feb. until 1 March 2017
Closest Moon approach0.70 LD at 1402 UT on 25 Feb. 2017
Inside one LD of Moon0718-2044 UT on 25 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 24 Feb. 2017 UTC
based on 32 observations spanning one day
Optical observation  
  • reported from 5 observing codes during 1.6060 days: 474, 691, G96, I52, J95
  • designation assigned to Mt. Lemmon Survey observation at 0619 UT 22 Feb. 2017
  • last observed at 2052 UT on 23 Feb. 2017 by Great Shefford Obs.
Links  
2017 DK34   -     departed
Approximate diameter15 meters (H=26.792)
Closest Earth approach6.16 LD at 1422 UT on 13 Feb. 2017
Inside ten LD of Earth9 to 17 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 24 Feb. 2017 UTC
based on 38 observations spanning 5 days
Optical observation  
  • reported from 5 observing codes during 4.7822 days: 691, F51, G96, H01, I52
  • first observed at 1344 UT on 17 Feb. 2017 by Pan-STARRS 1
  • designation assigned to Mt. Lemmon Survey observation at 0743 UT 21 Feb. 2017
  • last observed at 0831 UT on 22 Feb. 2017 by Steward Obs. Mt. Lemmon Station
Links  
2017 DJ16   -   approaching
Approximate diameter23 meters (H=25.819)
Closest Earth approach4.06 LD at 2148 UT on 28 Feb. 2017
Inside ten LD of Earth25 Feb. until 4 March 2017
Data based onJPL SSD orbit solution #2 downloaded from JPL on 24 Feb. 2017 UTC
based on 40 observations spanning 2 days
Optical observation  
  • reported from 7 observing codes during 2.6012 days: 691, G45, G96, I52, J69, K88, O75
  • designation assigned to Mt. Lemmon Survey observation at 0744 UT 21 Feb. 2017
  • last observed at 2210 UT on 23 Feb. 2017 by North Obs.
NotesNHATS target
Links  
2017 DH16   -     departed
Approximate diameter13 meters (H=27.066)
Closest Earth approach3.33 LD at 2314 UT on 17 Feb. 2017 - Note: JPL reports an approach uncertainty of +/- 2 minutes
Inside ten LD of Earth13 to 22 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 23 Feb. 2017 UTC
based on 27 observations spanning one day
Optical observation  
  • reported from 5 observing codes during 23.971 hours: 204, G96, H01, I52, K88
  • designation assigned to Mt. Lemmon Survey observation at 0715 UT 21 Feb. 2017
  • last observed at 0713 UT on 22 Feb. 2017 by Steward Obs. Mt. Lemmon Station
NotesNHATS target
Links  
2017 DG16   -   outbound intruder
Approximate diameter4 meters (H=29.45)
Closest Earth approach0.36 LD at 2107 UT on 23 Feb. 2017
Inside Earth-Moon system0607 on 23 Feb. until 1207 UT on 24 Feb. 2017
Inside Earth SOI22 to 25 Feb. 2017
Inside ten LD of Earth17 Feb. until 2 March 2017
Closest Moon approach0.18 LD at 1150 UT on 24 Feb. 2017
Inside one LD of Moon2043 on 23 Feb. until 0304 UT on 25 Feb. 2017
Data based onJPL SSD orbit solution #3 downloaded from JPL on 24 Feb. 2017 UTC
based on 37 observations spanning 2 days
Optical observation  
  • reported from 6 observing codes during 2.5680 days: 958, G96, H01, H36, I52, J95
  • designation assigned to Mt. Lemmon Survey observation at 0539 UT 21 Feb. 2017
  • last observed at 1917 UT on 23 Feb. 2017 by Great Shefford Obs.
Notesrisk, NHATS target
Links  
2017 DV15   -   outbound
Approximate diameter31 meters (H=25.179)
Closest Earth approach8.76 LD at 0316 UT on 21 Feb. 2017
Inside ten LD of Earth18 to 24 Feb. 2017
Data based onJPL SSD orbit solution #2 downloaded from JPL on 22 Feb. 2017 UTC
based on 72 observations spanning 33 days
Optical observation  
  • reported from 14 observing codes during 32.6600 days: 104, 204, 300, 474, 850, 958, A29, B49, E23, F51, Q62, T05, W25, Y00
  • first observed at 0831 UT on 20 Jan. 2017 by Pan-STARRS 1
  • designation assigned to ATLAS Haleakala observation at 1130 UT 19 Feb. 2017
  • last observed at 0021 UT on 22 Feb. 2017 by Schiaparelli Obs.
Links  
2017 DS15   -     departed
Approximate diameter26 meters (H=25.611)
Closest Earth approach6.51 LD at 2227 UT on 13 Feb. 2017
Inside ten LD of Earth12 to 15 Feb. 2017
Data based onJPL SSD orbit solution #2 downloaded from JPL on 23 Feb. 2017 UTC
based on 35 observations spanning 4 days
Optical observation  
  • reported from 10 observing codes during 4.1163 days: 104, 291, 587, 691, F51, H21, H36, I52, I93, J95
  • designation assigned to Pan-STARRS 1 observation at 0546 UT 18 Feb. 2017
  • last observed at 0833 UT on 22 Feb. 2017 by Pan-STARRS 1
Links  
2017 DF   -   outbound
Approximate diameter16 meters (H=26.565)
Closest Earth approach2.09 LD at 0926 UT on 19 Feb. 2017
Inside Earth SOI18 to 20 Feb. 2017
Inside ten LD of Earth11 to 27 Feb. 2017
Closest Moon approach2.16 LD at 2304 UT on 19 Feb. 2017
Data based onJPL SSD orbit solution #5 downloaded from JPL on 23 Feb. 2017 UTC
based on 63 observations spanning 5 days
Optical observation  
  • reported from 15 observing codes during 5.4642 days: 160, 203, 474, 958, B49, G96, H21, I52, I93, J08, J22, J95, K30, W25, Z84
  • designation assigned to Mt. Lemmon Survey observation at 0428 UT 17 Feb. 2017
  • last observed at 1536 UT on 22 Feb. 2017 by Mt. John Obs.
NotesNHATS target
Links  
2017 DB   -   outbound
Approximate diameter13 meters (H=27.028)
Closest Earth approach1.82 LD at 1633 UT on 20 Feb. 2017
Inside Earth SOI19 to 21 Feb. 2017
Inside ten LD of Earth15 to 26 Feb. 2017
Closest Moon approach2.74 LD at 0107 UT on 21 Feb. 2017
Data based onJPL SSD orbit solution #3 downloaded from JPL on 19 Feb. 2017 UTC
based on 56 observations spanning 2 days
Optical observation  
  • reported from 10 observing codes during 2.4150 days: 203, 246, 595, 958, G96, H01, H21, I93, J95, Z84
  • designation assigned to Mt. Lemmon Survey observation at 0900 UT 16 Feb. 2017
  • last observed at 1858 UT on 18 Feb. 2017 by Great Shefford Obs.
NotesNHATS target
Links  
2017 CP32   -     departed
Approximate diameter55 meters (H=23.966)
Closest Earth approach2.39 LD at 0533 UT on 12 Feb. 2017
Inside Earth SOIduring 12 Feb. 2017
Inside ten LD of Earth8 to 16 Feb. 2017
Data based onJPL SSD orbit solution #3 downloaded from JPL on 21 Feb. 2017 UTC
based on 35 observations spanning 5 days
Optical observation  
  • reported from 7 observing codes during 5.0936 days: 246, 474, 807, E23, H36, Q62, T05
  • designation assigned to ATLAS Haleakala observation at 0705 UT 15 Feb. 2017
  • last observed at 0920 UT on 20 Feb. 2017 by Mt. John Obs.
Links  
2017 CF32   -     departed
Approximate diameter21 meters (H=26.068)
Closest Earth approach2.57 LD at 0542 UT on 10 Feb. 2017
Inside ten LD of Earth30 Jan. until 20 Feb. 2017
Data based onJPL SSD orbit solution #7 downloaded from JPL on 23 Feb. 2017 UTC
based on 130 observations spanning 8 days
Optical observation  
  • reported from 24 observing codes during 7.9317 days: 104, 160, 203, 204, 246, 587, 595, 718, 850, 958, B75, F51, G34, G40, G45, H21, H36, K30, K38, K61, T05, W25, Z21, Z80
  • designation assigned to ATLAS Haleakala observation at 1016 UT 14 Feb. 2017
  • last observed at 0838 UT on 22 Feb. 2017 by the Space Surveillance Telescope Atom Site
Notesradar target, NHATS target
Links  
2017 CX31   -     departed
Approximate diameter32 meters (H=25.11)
Closest Earth approach3.03 LD at 0845 UT on 7 Feb. 2017
Inside ten LD of Earth2 to 12 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 12 Feb. 2017 UTC
based on 45 observations spanning 3 days
Optical observation  
Links  
2017 CR5   -     departed
Approximate diameter14 meters (H=26.949)
Closest Earth approach8.27 LD at 0817 UT on 6 Feb. 2017
Inside ten LD of Earth2 to 9 Feb. 2017
Data based onJPL SSD orbit solution #1 downloaded from JPL on 10 Feb. 2017 UTC
based on 13 observations spanning 3 days
Optical observation  
  • reported from 2 observing codes during 2.9556 days: G96, H01
  • designation assigned to Mt. Lemmon Survey observation at 0915 UT 6 Feb. 2017
  • last observed at 0811 UT on 9 Feb. 2017 by Magdalena Ridge Obs.
Links  
2017 CP1   -   passing
Approximate diameter41 meters (H=24.609)
Closest Earth approach3.58 LD at 1026 UT on 24 Feb. 2017
Inside ten LD of Earth15 Feb. until 5 March 2017
Data based onJPL SSD orbit solution #14 downloaded from JPL on 24 Feb. 2017 UTC
based on 210 observations spanning 20 days
Optical observation  
  • reported from 32 observing codes during 19.7225 days: 107, 108, 113, 130, 151, 160, 203, 204, 246, 705, A48, A53, B67, C77, F65, G40, G96, H01, H21, H45, I15, I52, J69, J95, K82, L04, Q62, T08, W34, Y00, Z80, Z99
  • designation assigned to Mt. Lemmon Survey observation at 0803 UT 3 Feb. 2017
  • last observed at 0124 UT on 23 Feb. 2017 by SONEAR
Notesradar target, NHATS target
Links  
2017 CS   -   approaching
Approximate diameter437 meters (H=19.445)
Closest Earth approach7.93 LD at 1552 UT on 29 May 2017 - Note: JPL reports an approach uncertainty of +/- 22 minutes
Inside ten LD of Earth26 May until 1 June 2017
Data based onJPL SSD orbit solution #8 downloaded from JPL on 22 Feb. 2017 UTC
based on 41 observations spanning 33 days
Optical observation  
  • reported from 6 observing codes during 32.7246 days: 291, 691, 695, 807, F51, Q62
  • first observed at 1339 UT on 20 Jan. 2017 by Pan-STARRS 1
  • designation assigned to Pan-STARRS 1 observation at 1205 UT 2 Feb. 2017
  • last observed at 0703 UT on 22 Feb. 2017 by the Spacewatch 0.9m telescope
Links  
2017 BY93   -   outbound
Approximate diameter81 meters (H=23.095)
Closest Earth approach2.37 LD at 2159 UT on 23 Feb. 2017
Inside Earth SOI23 to 24 Feb. 2017
Inside ten LD of Earth21 to 26 Feb. 2017
Data based onJPL SSD orbit solution #14 downloaded from JPL on 24 Feb. 2017 UTC
based on 149 observations spanning 28 days
Optical observation  
  • reported from 24 observing codes during 28.1154 days: 107, 160, 203, 246, 291, 474, 568, 695, 807, B67, F51, G40, H21, K92, K93, Q62, Q63, Q68, T05, T08, W25, W85, W86, Z80
  • designation assigned to Pan-STARRS 1 observation at 1159 UT 26 Jan. 2017
  • last observed at 1445 UT on 23 Feb. 2017 by Mt. John Obs.
Notesrisk, radar target
Links  
2017 BG30   -     departed
Approximate diameter4 meters (H=29.402)
Closest Earth approach2.48 LD at 1324 UT on 5 Feb. 2017
Inside ten LD of Earth23 Jan. until 18 Feb. 2017
Data based onJPL SSD orbit solution #5 downloaded from JPL on 3 Feb. 2017 UTC
based on 37 observations spanning 5 days
Optical observation  
  • reported from 6 observing codes during 5.2431 days: 705, F51, G96, H01, I52, K88
  • designation assigned to Mt. Lemmon Survey observation at 0515 UT 28 Jan. 2017
  • last observed at 1105 UT on 2 Feb. 2017 by Pan-STARRS 1
NotesNHATS target
Links  
2017 BY   -     departed
Approximate diameter28 meters (H=25.426)
Closest Earth approach5.28 LD at 0217 UT on 8 Jan. 2017
Inside ten LD of Earth31 Dec. until 15 Jan. 2017
Data based onJPL SSD orbit solution #7 downloaded from JPL on 19 Feb. 2017 UTC
based on 54 observations spanning 29 days
Optical observation  
  • reported from 14 observing codes during 28.6384 days: 104, 204, 246, 691, 807, 926, F51, H21, I52, I93, J04, J95, K88, K93
  • designation assigned to Pan-STARRS 1 observation at 1332 UT 20 Jan. 2017
  • last observed at 0451 UT on 18 Feb. 2017 by ARO Westfield
NotesNHATS target
Links  
2017 BW   -   outbound
Approximate diameter69 meters (H=23.466)
Closest Earth approach4.63 LD at 0140 UT on 17 Feb. 2017
Inside ten LD of Earth9 to 25 Feb. 2017
Data based onJPL SSD orbit solution #28 downloaded from JPL on 22 Feb. 2017 UTC
based on 404 observations spanning 31 days
Optical observation  
  • reported from 42 observing codes during 30.0381 days: 046, 160, 203, 204, 246, 474, 557, 587, 595, 703, 705, B75, C23, F51, F65, G34, G40, G45, G58, G96, H06, H21, H36, H45, J69, K30, K74, K82, K88, K93, Q62, T05, T08, T12, V37, W85, W86, W87, W88, Y00, Z45, Z80
  • designation assigned to GINOP-KHK observation at 2347 UT 19 Jan. 2017
  • last observed at 0042 UT on 19 Feb. 2017 by North Obs.
Notesradar target, NHATS target
Links  
2017 AG5   -     departed
Approximate diameter107 meters (H=22.5)
Closest Earth approach4.57 LD at 2145 UT on 30 Dec. 2016
Inside ten LD of Earth26 Dec. until 4 Jan. 2017
Data based onJPL SSD orbit solution #22 downloaded from JPL on 22 Feb. 2017 UTC
based on 494 observations spanning 47 days
Optical observation  
  • reported from 61 observing codes during 47.2416 days: 104, 107, 118, 130, 160, 203, 204, 246, 300, 510, 587, 595, 658, 691, 718, 926, 958, A48, B49, B67, B96, C23, C27, C42, C43, C44, C77, D29, F51, G45, G96, H06, H21, H36, H45, I15, I52, I57, I58, I89, I93, J08, J67, J69, J95, K26, K30, K32, K33, K38, K61, K63, K74, K80, L04, T05, Y00, Z45, Z48, Z80, Z98
  • first observed at 0137 UT on 5 Jan. 2017 by the Space Surveillance Telescope Atom Site
  • designation assigned to Mt. Lemmon Survey observation at 0350 UT 5 Jan. 2017
  • last observed at 0725 UT on 21 Feb. 2017 by Pan-STARRS 1
NotesNHATS target
Links  
2015 TC25   -   approaching
Approximate diameter4 meters (H=29.5)
Closest Earth approach7.63 LD at 1449 UT on 26 March 2017 - Note: JPL reports an approach uncertainty of +/- 6 minutes
Inside ten LD of Earth17 March until 4 April 2017
Data based onJPL SSD orbit solution #10 downloaded from JPL on 4 Feb. 2017 UTC (dated 28 Oct. 2015 local)
based on 29 observations spanning 7 days including radar
Optical observation  
    none recent
Notesrisk, radar target, NHATS target
previous passage Oct. 2015 at 0.29 LD
Links  
2014 JO25   -   approaching
Approximate diameter812 meters (H=18.1)
Closest Earth approach4.57 LD at 1223 UT on 19 April 2017
Inside ten LD of Earth18 to 20 April 2017
Data based onJPL SSD orbit solution #21 downloaded from JPL on 4 Feb. 2017 UTC (dated 7 Sept. 2016 local)
based on 174 observations spanning 2011-2016
Optical observation  
    none recent
Notesradar target
previous observation May 2011, observation May-June 2014, and observation Sept. 2016
Links  
2012 DR32   -   approaching
Approximate diameter41 meters (H=24.6)
Closest Earth approach2.67 LD at 1651 UT on 2 March 2017 - Note: JPL reports an approach uncertainty of +/- 4.1333 hours
Inside ten LD of Earth28 Feb. until 5 March 2017
Data based onJPL SSD orbit solution #5 downloaded from JPL on 4 Feb. 2017 UTC (dated 13 June 2014 local)
based on 53 observations spanning 4 days
Optical observation  
    none recent
Notesprevious passage March 2012 at 8.69 LD
Links  
2001 FE90   -     distant
Approximate diameter245 meters (H=20.7)
Distance from Earth290.9 LD during the observation period
Data based onJPL SSD orbit solution #54 downloaded from JPL on 22 Feb. 2017 UTC
based on 287 observations spanning 2001-2017 including radar
Optical observation  
  • reported from one observing code during 0.564 hours: F51
  • first observed at 0713 UT on 21 Feb. 2017 by Pan-STARRS 1
  • last observed at 0747 UT on 21 Feb. 2017 by Pan-STARRS 1
Notesprevious passage June 2009 at 6.99 LD
Links  
1998 SL36   -   approaching
Approximate diameter309 meters (H=20.2)
Closest Earth approach8.34 LD at 1329 UT on 16 March 2017
Inside ten LD of Earth14 to 18 March 2017
Data based onJPL SSD orbit solution #26 downloaded from JPL on 4 Feb. 2017 UTC
based on 88 observations spanning 1998-2016
Optical observation  
    none recent
Notesradar target
previous observation Aug.-Dec. 2016
Links  

Footnotes

Illustration of ten lunar distances.

1. Ten lunar distances:  A "lunar distance" (LD) is the average distance between Earth and Moon (about 384,400 km., the same as 238,855 miles or nearly ten [9.59] times around Earth's equator). Ten lunar distances has no special astronomical importance but is a useful arbitrary "bubble" within which to organize this reporting. An approach by a small Solar-System body starts to become interesting at less than four LD out from Earth as it encounters our planet's "Hill sphere" (distance indicated by the blue line in this illustration at about 3.9 LD). This is a region within which Earth's gravitational influence can change the orbits of passing objects. The Moon also has a Hill sphere, outlined here as a gray circle. (Earth and Moon are not shown to scale.) The "Earth-Moon system" is generally defined as that region of space within a radius of one lunar distance from Earth, so an object can pass very close to the Moon yet not be described as coming "inside" the E-M system.

2. Data credit:  All data on this page derived from orbit solutions comes from the NASA JPL Solar System Dynamics (SSD) Group through its Horizons system. All information about optical observations comes from the IAU Minor Planet Center (MPC) and info about radar observations comes from JPL SSD. The MPC, NASA, and JPL are not associated with this page or A/CC, and responsibility for the interpretation of this information and its use here rests entirely with A/CC. Important note: Approach times presented here as to-the-minute may have unstated uncertainties of a few minutes, or many minutes or even hours for objects with old or very short observation spans, which is significant because the Earth moves through its own diameter in about seven minutes. Thus actual encounter distances may vary, occasionally by as much as ten lunar distances. See JPL's Close Approach Tables for nominal vs. minimum possible passage distances and times and for their note about uncertainties.

3. Size estimates:  Object diameters are rough approximations derived by standard formula from H, an object's "absolute magnitude" (brightness), where higher numbers represent dimmer (thus usually smaller) objects.