Contents  on 4 December '19

Asteroid/Comet Connection (A/CC) Resources:

The latest A/CC news is available via framed access, RSS news feed RSS news feed, or redirection.

Navigation tips: Use the << and >> arrows on the menus for each regular section (Observers, Risks, etc.) to move to the previous and next day's news for that section. Use the Index menu item to access specific days through a calendar interface. To keep track of what's new each day, watch the Chronology section.

Traffic Report  on 4 December '19

Eight objects reported inside ten LD

Bulletin - 2354, updated 0019 UTC:  Three new discoveries of close passers have been announced.

Earth passageI D~Size~Inside ten LDNotes
3.17 LD at 0454 UTC Dec. 92019 XY9 m  unavailable MPEC
3.89 LD at 1518 UTC Nov. 192019 XV5 m  unavailable MPEC
6.36 LD at 0500 UTC Dec. 142019 WP620 m  unavailable MPEC


Eight asteroids are reported to be less than ten lunar distances (LD) from Earth today. The nearest, 2019 XN, is inbound from 5.9 to 4.1 LD*.

Neighborhood Traffic - sorted by Earth passage distance, grouped by 1.0, 2.41, 5.0 & 10.0 LD boundaries
Earth passage I D ~Size Distance today  Inside ten LD Notes
2.4   LD Dec. 6* 2019 XN 10 m  4.1 from 5.9 LD Dec. 2 - 10 EPU +/- 16 mins.* - MPEC
3.43 LD Dec. 1 2019 WH2 15 m  6.89 to 8.95 LD Nov. 27 - tomorrow
4.3   LD Dec. 1* 2019 WN1 17 m  6.4 to 8.3 LD Nov. 27 - tomorrow EPU +/- 3.15 hours*
4.8   LD Dec. 9* 2019 WO2 32 m  9.4 from 11.0 LD today - Dec. 14 EPU +/- 10 mins.*, enters ten LD
5.5   LD Dec. 7* 2019 XP 15 m  9.6 from 11.9 LD today - Dec. 10 NEW, EPU +/- 35 mins.*, enters ten LD - MPEC
5.81 LD Dec. 2 2019 WH4 11 m  6.64 to 7.68 LD Nov. 27 - Dec. 6 risk - DOU
8.5   LD yesterday* 2017 AP4 14 m  8.5 to 8.7 LD Nov. 30 - Dec. 7 EPU +/- 2.97 days*
8.61 LD tomorrow 2019 WW 42 m  8.61 from 8.92 LD Dec. 2 - 7 NHATS target - DOU
Approaching - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
7.45 LD Dec. 7 2019 WJ6 44 m  14.30 from 18.53 LD Dec. 6 - 8
9.78 LD Dec. 9 2019 WT3 38 m  15.00 from 16.98 LD Dec. 8 - 10 DOU
9.5   LD Dec. 18* 2019 XF 74 m  73.5 from 79.1 LD Dec. 17 - 18 EPU +/- 3.65 hours*
6.3   LD Jan. 11* 2019 WC5 107 m  118.6 from 122.2 LD Jan. 8 - 13 EPU +/- 14.68 hours*, risk
* EPU = Earth passage uncertainty

This report was generated at 1940 UTC with four discoveries, starting with two from late yesterday: inbound 2019 XN (MPEC) and already departed 2019 XM (MPEC), which went by us at 5.18 LD on November 30th. Today we have inbound 2019 XP (MPEC) and departed 2019 XR (MPEC), which flew past at about 3.6 LD* on November 28th. Today's DOU MPEC has follow-up for approaching 2019 WT3, inbound 2019 WW, outbound risk-listed 2019 WH4, and four departed objects: 2019 WQ3, 2019 WK2, 2019 WV, and risk-listed 2019 WG2, plus astrometry from earlier this year and other years for 55 objects, including four risk-listed from this year.



Notes: Ten times the distance to the Moon (ten LD) has no astronomical importance but is a useful boundary for reporting about transient natural objects that approach our planet's gravitational sphere of influence (SOI), which has a radius of about 2.41 LD from Earth's center. This puts a focus on some of the most important and very best NEO observation work, representative of the much larger NEO discovery and tracking effort. Object temporal distances are derived by A/CC from JPL Horizons data. "LD*" indicates some uncertainty in object passage time and distance. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

NEOCP Activity  on 4 December '19

The MPC's NEO Confirmation Page has 74 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 74 objects listed. Of these, 37 were "one nighters." So far The Tracking News has counted a total of 92 listings on the NEOCP today.

To learn how observers use the NEOCP, see the Practical guide on how to observe NEOCP object at Suno Observatory by Birtwhistle et al.

New MPECs  on 4 December '19

Minor Planet Electronic Circulars

As of last check at 2359 UTC, there have been fourteen MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2019-X55 - "23:53 UT" - 2019 XY


MPEC 2019-X54 - "23:52 UT" - 2019 XX


MPEC 2019-X53 - "23:41 UT" - 2019 XW


MPEC 2019-X52 - "23:38 UT" - 2019 WP6


MPEC 2019-X51 - "23:33 UT" - 2019 XV


MPEC 2019-X50 - "16:23 UT" - 2002 XE84


<< DOU on 4 December '19 >>  MPEC 2019-X49 - "12:03 UT" - Daily Orbit Update


MPEC 2019-X48 - "02:59 UT" - 2019 XT


MPEC 2019-X47 - "02:56 UT" - 2019 XS


MPEC 2019-X46 - "02:49 UT" - 2019 WN6


MPEC 2019-X45 - "02:40 UT" - 2019 XR


MPEC 2019-X44 - "02:35 UT" - 2019 XQ


MPEC 2019-X43 - "02:29 UT" - 2019 XP


MPEC 2019-X42 - "02:26 UT" - 2019 XO

Observers  on 4 December '19

A total of 70 observers appear in today's MPECs.

CodeObserver / observatory
705"Kristie Nault via Apache Point Obs. in New Mexico, 1 in MPEC 2019-X49 -- 2016 TV10
H21Astronomical Research Obs. Westfield in Illinois, 39 in MPECs 2019-X49, 2019-X53, 2019-X54 & 2019-X55 -- 2019 XY, 2019 XX, 2019 XW, 2019 WW, 2019 WV, 2019 WK2, 2019 WG, 2019 VL4, 2019 UX9, 2019 UX1, 2019 UN3, 2019 UK6, 2019 UK13, 2019 TQ3, 2019 TN, 2019 TJ4, 2019 SV, 2019 SM7, 2019 SH6, 2019 SC7, 2019 RR1, 2019 RO1, 2019 RN4, 2019 QU4, 2019 PT1, 2019 PJ1, 2019 OF4, 2019 OE4, 2019 NX6, 2019 MH, 2019 KY3, 2018 XL1, 2018 XG5, 2015 VL142, 2015 HG170, 254419, 162723, 106538, 5189
T05ATLAS Haleakala in Hawaii, 15 in MPECs 2019-X49 & 2019-X50 -- 2002 XE84, 99248, 85236, 528609, 448818, 437316, 344074, 22771, 192563, 18172, 163696, 137084, 136795, 6455, 3552
T08ATLAS Mauna Loa in Hawaii, 23 in MPECs 2019-X49, 2019-X53 & 2019-X54 -- 2019 XX, 2019 XW, 2016 UT80, 87311, 481984, 458745, 409342, 354030, 35107, 349063, 30825, 275975, 177651, 171486, 143947, 138013, 137199, 11405, 106538, 7088, 5626, 3102, 2102
300Bisei Spaceguard Center in Japan, 1 in MPEC 2019-X49 -- 2017 DA38
Z84Calar Alto Schmidt in Spain, 6 in MPEC 2019-X49 -- 2019 UR6, 2019 UP7, 2019 TT2, 2019 TN1, 2019 LQ1, 2014 VA
160Castelmartini Obs. in Italy, 1 in MPEC 2019-X49 -- 2017 TK6
703Catalina Sky Survey (CSS) in Arizona, 38 in MPECs 2019-X43, 2019-X44 & 2019-X49 -- 2019 XQ, 2019 XP, 2019 WZ, 2019 WR2, 2019 VL4, 2019 VH5, 2019 UO, 2019 UB11, 2019 QT8, 2019 OP2, 2019 GW1, 2016 UT80, 2014 HH192, 88959, 86067, 85628, 483878, 450293, 36236, 349063, 347813, 329340, 294739, 275975, 214088, 159504, 153814, 141498, 138852, 136849, 11066, 106538, 10115, 7088, 5693, 5626, 5189, 1620
V06Catalina Sky Survey Kuiper Telescope in Arizona, 1 in MPEC 2019-X49 -- 2017 WD16
K51Celado Obs. in Italy, 3 in MPECs 2019-X51, 2019-X53 & 2019-X54 -- 2019 XX, 2019 XW, 2019 XV
G58Chabot Obs. in northern California, 1 in MPEC 2019-X49 -- 2017 UP5
Z99Clixby Obs. in England, 3 in MPECs 2019-X44, 2019-X50 & 2019-X53 -- 2019 XW, 2019 XQ, 2002 XE84
N55Corona Borealis Obs. in Tibet, 1 in MPEC 2019-X49 -- 2015 QN3
I39Cruz del Sur Obs. in Argentina, 1 in MPEC 2019-X49 -- 2015 BL311
958Dax Obs. in France, 1 in MPEC 2019-X49 -- 2019 QU4
K87Dettelbach Vineyard Obs. in Germany, 1 in MPEC 2019-X54 -- 2019 XX
113Drebach Obs. in Germany, 1 in MPEC 2019-X49 -- 2015 HL1
I48El Catalejo Obs. in Argentina, 1 in MPEC 2019-X49 -- 2019 UR12
J04ESA Optical Ground Station in the Canary Islands, 1 in MPEC 2019-X49 -- 2019 QU4
734Farpoint Obs. in Kansas, 7 in MPECs 2019-X49 & 2019-X54 -- 2019 XX, 2019 WT3, 2019 VS5, 2019 VO1, 2019 UC7, 2019 SH6, 2019 QT8
595Farra d'Isonzo Obs. in Italy, 3 in MPECs 2019-X49, 2019-X50 & 2019-X54 -- 2019 XX, 2016 TH94, 2002 XE84
F65Faulkes Telescope North in Hawaii, 1 in MPEC 2019-X49 -- 2019 JY4
F652Lothar Kurtze in Germany via Faulkes Telescope North in Hawaii, 1 in MPEC 2019-X49 -- 2019 AV7
X31Galilei Obs., 1 in MPEC 2019-X49 -- 2019 UC
203GiaGa Obs. in Italy, 1 in MPEC 2019-X49 -- 2019 QU4
K88GINOP-KHK in Hungary, 3 in MPECs 2019-X50, 2019-X53 & 2019-X54 -- 2019 XX, 2019 XW, 2002 XE84
J95Great Shefford Obs. in England, 7 in MPECs 2019-X42, 2019-X43, 2019-X44, 2019-X49, 2019-X53 & 2019-X54 -- 2019 XX, 2019 XW, 2019 XQ, 2019 XP, 2019 XO, 2016 TX10, 2016 TJ17
A17Guidestar Obs. in Germany, 5 in MPECs 2019-X49, 2019-X50 & 2019-X53 -- 2019 XW, 2019 SC, 2015 WH13, 2014 QQ266, 2002 XE84
G48Harlingten Research Obs. in New Mexico, 1 in MPEC 2019-X49 -- 2017 RV1
C43Hoyerswerda Obs. in Germany, 1 in MPEC 2019-X49 -- 2015 KO57
O75ISON Hureltogoot Obs. in Mongolia, 1 in MPEC 2019-X49 -- 2014 UN114
H06|Hidetaka Sato in Japan via iTelescope Obs. Mayhill in New Mexico, 1 in MPEC 2019-X49 -- 2019 UD13
P93JAXA Space Tracking & Communications Center in Japan, 1 in MPEC 2019-X49 -- 2018 VR9
246KLENOT in the Czech Republic, 4 in MPECs 2019-X49 & 2019-X53 -- 2019 XW, 2019 RC, 2019 GB, 2018 MW6
K42Knielingen Obs., 1 in MPEC 2019-X49 -- 2019 LZ4
Z43Landehen Obs., 2 in MPEC 2019-X49 -- 344074, 338347
W86LCO Cerro Tololo B in Chile, 1 in MPEC 2019-X49 -- 2019 WT3
K91LCO Sutherland A in South Africa, 1 in MPEC 2019-X49 -- 2019 SP3
598Loiano Obs. in Italy, 2 in MPEC 2019-X49 -- 2019 WY3, 2019 WT4
568^R. Wainscoat on Mauna Kea in Hawaii, 1 in MPEC 2019-X52 -- 2019 WP6
711McDonald Obs. in Texas, 7 in MPEC 2019-X49 -- 2019 UV6, 2019 UM9, 2019 UL10, 2019 UJ9, 2018 CY, 2017 YS3, 2014 JR25
474Mt. John Obs. in New Zealand, 3 in MPECs 2019-X49 & 2019-X54 -- 2019 XX, 2019 PJ, 2019 PH
G96Mt. Lemmon Survey (MLS) in Arizona, 34 in MPECs 2019-X42, 2019-X45, 2019-X46, 2019-X47, 2019-X48, 2019-X49, 2019-X50, 2019-X51 & 2019-X55 -- 2019 XY, 2019 XV, 2019 XT, 2019 XS, 2019 XR, 2019 XO, 2019 WZ, 2019 WY3, 2019 WT4, 2019 WT, 2019 WP4, 2019 WO4, 2019 WN6, 2019 WL2, 2019 UH4, 2019 LE5, 2016 XA24, 2016 TX17, 2016 TW18, 2016 TA18, 2015 TO237, 2015 NW9, 2013 UV10, 2013 UM5, 2009 WP25, 2006 KF89, 2002 XE84, 482344, 427621, 38091, 36236, 277958, 152978, 137052
C82Nastro Verde Obs. in Italy, 1 in MPEC 2019-X49 -- 2018 UA1
0895N.V. Maigurova via Nikolaev Obs. in Ukraine, 1 in MPEC 2019-X49 -- 2019 JV1
J69North Obs. in England, 2 in MPECs 2019-X49 & 2019-X53 -- 2019 XW, 2019 TA4
Z80Northolt Branch Obs. in England, 6 in MPECs 2019-X49 & 2019-X53 -- 2019 XW, 2019 WR3, 2019 WQ3, 2019 UO, 2018 SF2, 216258
C23Olmen Obs. in Belgium, 1 in MPEC 2019-X49 -- 2015 SZ2
F51Pan-STARRS 1 (PS1) in Hawaii, 46 in MPECs 2019-X45, 2019-X46, 2019-X49 & 2019-X53 -- 2019 XW, 2019 XR, 2019 WN6, 2019 WK5, 2019 WG2, 2019 VX5, 2019 SN3, 2019 QL7, 2019 LK5, 2018 MJ, 2018 FA3, 2017 UJ44, 2017 RE16, 2017 BY5, 2017 AD3, 2016 TX18, 2016 SQ3, 2016 RZ19, 2016 RY19, 2016 NG38, 2016 HN2, 2016 GV221, 2016 GP206, 2016 GK135, 2016 EP55, 2015 XH379, 2015 PL9, 2015 NU2, 2015 KY56, 2015 DD200, 2015 CH13, 2014 WP7, 2013 YO139, 2010 JL41, 2008 VN, 2008 AJ33, 529668, 397471, 349063, 285567, 15745, 141761, 138205, 7088, 4450, 1627
F52Pan-STARRS 2 (PS2) in Hawaii, 18 in MPECs 2019-X46, 2019-X49, 2019-X50 & 2019-X52 -- 2019 WP6, 2019 WN6, 2019 LL6, 2011 AO52, 2008 VN, 2008 SJ82, 2002 XE84, 90075, 52768, 506074, 467317, 386847, 331769, 276397, 232368, 163081, 5626, 3102
K63Pascoli Obs. in Italy, 5 in MPECs 2019-X49, 2019-X53 & 2019-X54 -- 2019 XX, 2019 XW, 2019 QY5, 2019 QT8, 4183
K19PASTIS Obs. in France, 1 in MPEC 2019-X49 -- 2019 PH1
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 16 in MPEC 2019-X49 -- 2019 WZ, 2019 WR3, 2019 UK6, 2019 SH6, 2019 QV5, 2019 QT8, 2019 PR2, 85236, 333555, 323179, 243025, 216258, 214088, 192563, 163696, 153814
586Pic du Midi Obs. in France, 1 in MPEC 2019-X49 -- 2019 SD8
6581Dave Balam via Plaskett 1.8m Telescope in British Columbia, 10 in MPEC 2019-X49 -- 2019 WW4, 2019 RG, 2019 QU1, 2019 QK4, 2019 PM, 2019 OT, 2019 OS1, 2019 OR1, 2019 OM, 2019 ET1
654Pomona College Table Mtn. Obs. in southern California, 1 in MPEC 2019-X49 -- 2019 RX1
K61Rokycany Obs. in the Czech Republic, 3 in MPECs 2019-X44, 2019-X50 & 2019-X53 -- 2019 XW, 2019 XQ, 2002 XE84
104San Marcello Pistoiese Obs. in Italy, 3 in MPEC 2019-X49 -- 2019 QS1, 2015 QN3, 36236
H36Sandlot Obs. in Kansas, 5 in MPECs 2019-X47, 2019-X49 & 2019-X50 -- 2019 XS, 2019 XB, 2019 QW3, 2015 VF1, 2002 XE84
C95SATINO-1 in France, 3 in MPEC 2019-X49 -- 2019 UF5, 2019 LU4, 2019 LB
204Schiaparelli Obs. in Italy, 1 in MPEC 2019-X49 -- 2017 XW61
033Schwarzschild Obs. in Germany, 19 in MPECs 2019-X49, 2019-X50, 2019-X51, 2019-X53, 2019-X54 & 2019-X55 -- 2019 XY, 2019 XX, 2019 XW, 2019 XV, 2019 WZ, 2019 WX, 2019 WR2, 2019 WH4, 2019 WD1, 2019 TO, 2019 SD11, 2019 KG2, 2019 GW1, 2019 BL4, 2017 FM102, 2016 AO66, 2015 DA156, 2009 HY51, 2002 XE84
587Sormano Obs. in Italy, 1 in MPEC 2019-X53 -- 2019 XW
691Spacewatch 0.9m telescope in Arizona, 4 in MPEC 2019-X49 -- 2019 UK, 2019 UB4, 2019 SU8, 2019 SL
I52Steward Obs. Mt. Lemmon Station in Arizona, 30 in MPECs 2019-X42, 2019-X43, 2019-X44, 2019-X45, 2019-X47, 2019-X48, 2019-X49, 2019-X50 & 2019-X51 -- 2019 XV, 2019 XT, 2019 XS, 2019 XR, 2019 XQ, 2019 XP, 2019 XO, 2019 UY6, 2019 UV7, 2019 UT5, 2019 UN3, 2019 UJ9, 2019 UH2, 2019 UC8, 2019 UA8, 2019 TP5, 2019 TP, 2019 TO5, 2019 TO, 2019 TK3, 2019 SU, 2019 ST8, 2019 SP, 2019 BJ1, 2017 VT14, 2016 TL18, 2016 TA18, 2016 GY2, 2016 GE1, 2002 XE84
954Teide Obs. in the Canary Islands, 1 in MPEC 2019-X49 -- 2019 AA9
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2019-X49 -- 2019 WG2
K41Vegaquattro Obs. in Italy, 3 in MPEC 2019-X49 -- 2019 DQ1, 2018 KD3, 2018 JE5
L01Visnjan Obs., 14 in MPECs 2019-X42, 2019-X43, 2019-X44, 2019-X47, 2019-X48, 2019-X49, 2019-X50, 2019-X51, 2019-X53, 2019-X54 & 2019-X55 -- 2019 XY, 2019 XX, 2019 XW, 2019 XV, 2019 XT, 2019 XS, 2019 XQ, 2019 XP, 2019 XO, 2019 TS, 2018 CV13, 2014 QQ266, 2014 HD177, 2002 XE84
C42Xingming Obs. in China, 1 in MPEC 2019-X49 -- 2017 BM3
I41Zwicky Transient Facility (ZTF) in southern California, 5 in MPEC 2019-X49 -- 2019 BL4, 99248, 85490, 459046, 192563
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 4 December '19

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2359 UTC)
See the CRT page for a list of all objects rated recently as risks and our ephemerides page for a list of risk-listed objects under current observation.
The time horizon for JPL and NEODyS listings is 100 years, and both post impact solutions beyond that for some special objects.
For the latest official risk assessments, and for explanations of the terminology, see the NASA/JPL Sentry and NEODyS CLOMON2 risk pages.
0000NNN000

Object

Risk
Monitor
When
Noted
UTC
0000T0000
Year
Range

VI
#
000NN00
Prob
Cum
T0000
PS
Cum
T0000
PS
Max

T
S


Notes for Today's Latest Risk Assessments
2019 XRJPL Sentry04332053-205314.466e-09-9.77-9.770JPL: Computed at 19:57 Dec. 3rd Pacific time based on 13 observations spanning 1.1201 days (2019-Dec-02.38857 to 2019-Dec-03.50863). Diameter approximately 0.008 km. from weighted mean H=28.07.
2019 XOJPL Sentry04332100-210011.220e-08-9.23-9.230JPL: Computed at 19:28 Dec. 3rd Pacific time based on 15 observations spanning .67893 days (2019-Dec-03.31664 to 2019-Dec-03.995568). Diameter approximately 0.013 km. from weighted mean H=27.11.
2019 XKNEODyS1530211243.32e-08-8.03-8.10NEODyS: "Based on 29 optical observations (of which 0 are rejected as outliers) from 2019-12-02.315 to 2019-12-03.875."
JPL Sentry04332112-211751.22092e-06-6.45-6.780JPL: Computed at 16:30 Dec. 3rd Pacific time based on 29 observations spanning 1.5592 days (2019-Dec-02.31468 to 2019-Dec-03.87389). Diameter approximately 0.025 km. from weighted mean H=25.69.
2019 WW4NEODyS17312036-2116461.47e-06-3.35-3.830NEODyS: "Based on 32 optical observations (of which 0 are rejected as outliers) from 2019-11-27.065 to 2019-12-03.204."
JPL Sentry17002036-2116261.7207008e-06-3.25-3.730JPL: Computed at 08:20 today Pacific time based on 32 observations spanning 6.1388 days (2019-Nov-27.06455 to 2019-Dec-03.20333). Diameter approximately 0.392 km. from weighted mean H=19.67.
2019 WH4NEODyS1731211311.11e-07-8.47-8.470NEODyS: "Based on 18 optical observations (of which 1 are rejected as outliers) from 2019-11-25.251 to 2019-12-02.141."
2019 WG2NEODyS17312093-21181075.79e-05-4.41-4.960NEODyS: "Based on 41 optical observations (of which 0 are rejected as outliers) from 2019-11-24.496 to 2019-12-03.435."
JPL Sentry17002098-2119520.000164524136-3.91-4.220JPL: Computed at 08:29 today Pacific time based on 41 observations spanning 8.9390 days (2019-Nov-24.495057 to 2019-Dec-03.434075). Diameter approximately 0.034 km. from weighted mean H=24.97.
2019 UT5NEODyS1731R E M O V E D-
JPL Sentry16312080-208012.364e-10-11.30-11.30JPL: Computed at 08:19 today Pacific time based on 24 observations spanning 5.2586 days (2019-Oct-24.29031 to 2019-Oct-29.548932). Diameter approximately 0.007 km. from weighted mean H=28.42.
2019 TP5NEODyS1731207815.74e-10-9.14-9.140NEODyS: "Based on 41 optical observations (of which 0 are rejected as outliers) from 2019-10-07.477 to 2019-10-17.173."
2019 SCNEODyS1731205111.05e-05-5.79-5.790NEODyS: "Based on 77 optical observations (of which 1 are rejected as outliers) from 2019-09-06.412 to 2019-09-20.120."
JPL Sentry17002051-205116.051e-06-6.01-6.010JPL: Computed at 08:22 today Pacific time based on 76 observations spanning 13.708 days (2019-Sep-06.411436 to 2019-Sep-20.119139). Diameter approximately 0.012 km. from weighted mean H=27.22.
2019 RT3JPL Sentry05552087-211762.01465e-06-6.08-6.280JPL: Computed at 20:31 Dec. 3rd Pacific time based on 119 observations spanning 67.590 days (2019-Sep-11.603747 to 2019-Nov-18.193259). Diameter approximately 0.031 km. from weighted mean H=25.20.
2019 KY3NEODyS17312101-211044.04e-07-7.22-7.310NEODyS: "Based on 40 optical observations (of which 3 are rejected as outliers) from 2019-05-31.272 to 2019-06-01.308."
JPL Sentry17002086-211036.7473e-07-7.01-7.230JPL: Computed at 08:20 today Pacific time based on 38 observations spanning 1.0195 days (2019-May-31.270846 to 2019-Jun-01.29035). Diameter approximately 0.017 km. from weighted mean H=26.55.

Legend: VI# = VI count, Prob Cum = cumulative probability, PS Cum/Max = cumulative/maximum Palermo Scale, TS = Torino Scale (next 100 years)

An impact solution, also known as a "virtual impactor" (VI), is not a prediction but rather a possibility derived from a variant orbit calculation that cannot be eliminated yet based on the existing data. Elimination can come quickly with just a little further observation or may take weeks or months, sometimes years. Once superceded or eliminated, a former impact solution has zero relevance to an object's risk. See Jon Giorgini's "Understanding Risk Pages" to learn more.

Chronology  on 4 December '19

Times are UTC for when items were noted or added by The Tracking News.

2359Grabbed MPEC 2019-X52 - 2019 WP6 - see above
Grabbed MPEC 2019-X53 - 2019 XW - see above
Grabbed MPEC 2019-X54 - 2019 XX - see above
Grabbed MPEC 2019-X55 - 2019 XY - see above
2334Grabbed MPEC 2019-X51 - 2019 XV - see above
1940Generated Traffic Report
1731Noted that NEODyS has updated its 2019 KY3 risk assessment - see above
Noted that NEODyS has updated its 2019 SC risk assessment - see above
Noted that NEODyS has updated its 2019 TP5 risk assessment - see above
Noted that NEODyS has removed 2019 UT5 as an impact risk - see above
Noted that NEODyS has updated its 2019 WG2 risk assessment - see above
Noted that NEODyS has reposted 2019 WH4 as an impact risk - see above
Noted that NEODyS has updated its 2019 WW4 risk assessment - see above
1700Noted that JPL Sentry has updated its 2019 KY3 risk assessment - see above
Noted that JPL Sentry has updated its 2019 SC risk assessment - see above
Noted that JPL Sentry has updated its 2019 WG2 risk assessment - see above
Noted that JPL Sentry has updated its 2019 WW4 risk assessment - see above
1631Noted that JPL Sentry has updated its 2019 UT5 risk assessment - see above
Grabbed MPEC 2019-X50 - 2002 XE84 - see above
1530Noted that NEODyS has posted 2019 XK as an impact risk - see above
Grabbed MPEC 2019-X49 - Daily Orbit Update - see above
0555Noted that JPL Sentry has updated its 2019 RT3 risk assessment - see above
0433Noted that JPL Sentry has posted 2019 XK as an impact risk - see above
Noted that JPL Sentry has posted 2019 XO as an impact risk - see above
Noted that JPL Sentry has posted 2019 XR as an impact risk - see above
Grabbed MPEC 2019-X42 - 2019 XO - see above
Grabbed MPEC 2019-X43 - 2019 XP - see above
Grabbed MPEC 2019-X44 - 2019 XQ - see above
Grabbed MPEC 2019-X45 - 2019 XR - see above
Grabbed MPEC 2019-X46 - 2019 WN6 - see above
Grabbed MPEC 2019-X47 - 2019 XS - see above
Grabbed MPEC 2019-X48 - 2019 XT - see above