Contents  on 28 November '18

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 28 November '18

Six objects reported inside ten LD

Six Solar-System small bodies are known to be within ten lunar distances (LD) of Earth today. The nearest is newly announced risk-listed 2018 WH1, which exits our planet's sphere of gravitational influence, slipping away from 2.24 to 3.06 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
0.28 LD Nov. 25 2018 WE1 22 m  7.90 to 10.54 LD Nov. 21 - 28 NEW, intruder, exits ten LD, risk - MPEC
0.65 LD Nov. 13 2018 WA1 3 m  9.13 to 9.74 LD Oct. 29 - tomorrow intruder, NHATS target, risk
1.18 LD Nov. 25 2018 WH1 7 m  2.24 to 3.06 LD Nov. 15 - Dec. 6 NEW, Moon buzzer, exits Earth SOI, risk - MPEC
3.92 LD Dec. 2 2018 TG6 12 m  4.05 from 4.13 LD Oct. 30 - Jan. 5 NHATS target
8.21 LD Nov. 25 2018 VT7 9 m  8.29 to 8.38 LD Nov. 15 - Dec. 7 NHATS target
9.44 LD today 2008 WD14 89 m  9.44 LD Nov. 26 - 29 Earth closest at 1005 UTC - MPEC

This report was generated at 2010 UTC with the discoveries of two outbound risk-listed objects: intruder 2018 WH1 (MPEC), which flew by us at 0.28 LD and the Moon at 0.55 LD early on November 25th, and 2018 WE1 (MPEC), which later the same day buzzed the Moon at 0.77 LD and passed Earth at 1.18 LD, and with the recovery (actually two recoveries, one in August) announced late yesterday of 2008 WD14 (MPEC), which turns out comes its closest on this passage today at 9.44 LD at 1005 UTC vs. the previous uncertain calculation of 7.4 LD at 0014 UTC yesterday. Today's DOU MPEC has follow-up for approaching objects 2018 VO9 (risk listed), 163899 2003 SD220, and 2001 XG1, and for departed objects 2018 WU (first follow-up, 8.05 days added to 1.93-day discovery arc), 2018 VM6, and risk-listed 2018 VC.

Approaching - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
2.63 LD Dec. 15 2018 VO9 14 m  10.48 from 11.06 LD tomorrow - Dec. 31 NHATS target, risk - DOU
4.1   LD Dec. 9* 2013 VX4 62 m  16.3 from 17.7 LD Dec. 3 - 15 EPU +/- 2.35 days*
7.84 LD Dec. 10 2001 XG1 74 m  36.67 from 39.92 LD Dec. 8 - 12 DOU
7.36 LD Dec. 22 163899 2003 SD220 1.17 km  31.99 from 33.23 LD Dec. 17 - 26 radar/NHATS target - DOU
7.3   LD Jan. 9* 2013 YM2 19 m  40.4 from 41.3 LD Jan. 2 - 16 EPU +/- 1.25 days*, NHATS target
* EPU = Earth passage uncertainty



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. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

NEOCP Activity  on 28 November '18

The MPC's NEO Confirmation Page has 41 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 41 objects listed. Of these, seventeen were "one nighters." So far The Tracking News has counted a total of 49 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 28 November '18

Minor Planet Electronic Circulars

As of last check at 2358 UTC, there have been five MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


<< DOU on 28 Nov. '18 >>  MPEC 2018-W69 - "13:05 UT" - Daily Orbit Update


MPEC 2018-W68 - "12:30 UT" - 2018 WJ1


MPEC 2018-W67 - "11:39 UT" - 2018 WH1


MPEC 2018-W66 - "03:31 UT" - 2018 WD1


MPEC 2018-W65 - "03:28 UT" - 2018 WE1

Observers  on 28 November '18

A total of 24 observers appear in today's MPECs.

CodeObserver / observatory
T05ATLAS Haleakala in Hawaii, 1 in MPEC 2018-W69 -- 2018 TC3
T08ATLAS Mauna Loa in Hawaii, 7 in MPECs 2018-W65 & 2018-W69 -- 2018 WE1, 2018 VF3, 2018 TS, 2018 QN1, 2001 XG1, 523811, 518735
C77Bernezzo Obs. in Italy, 2 in MPECs 2018-W65 & 2018-W67 -- 2018 WH1, 2018 WE1
703Catalina Sky Survey (CSS) in Arizona, 3 in MPECs 2018-W67 & 2018-W69 -- 2018 WH1, 523824, 163899
V06Catalina Sky Survey Kuiper Telescope in Arizona, 1 in MPEC 2018-W69 -- 2014 WE365
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 7 in MPEC 2018-W69 -- 2018 WU, 2018 UC1, 2018 TT, 2018 TO2, 2018 RM2, 2018 MM8, 2018 GA5
J95Great Shefford Obs. in England, 1 in MPEC 2018-W65 -- 2018 WE1
H01Magdalena Ridge Obs. (MRO) in New Mexico, 3 in MPECs 2018-W66, 2018-W67 & 2018-W68 -- 2018 WJ1, 2018 WH1, 2018 WD1
C94MASTER-II Tunka in Russia, 1 in MPEC 2018-W69 -- 1999 RB32
G96Mt. Lemmon Survey in Arizona, 1 in MPEC 2018-W68 -- 2018 WJ1
Z80Northolt Branch Obs. in England, 3 in MPECs 2018-W65 & 2018-W69 -- 2018 WE1, 2009 WB105, 138852
I41Palomar Transient Factory (PTF) in southern California, 6 in MPEC 2018-W69 -- 2009 TK8, 99935, 454177, 409204, 5332, 2062
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2018-W69 -- 2009 WB105
F52Pan-STARRS 2 in Hawaii, 1 in MPEC 2018-W68 -- 2018 WJ1
C95SATINO-1 in France, 3 in MPECs 2018-W65, 2018-W67 & 2018-W69 -- 2018 WH1, 2018 WE1, 2013 PA7
204Schiaparelli Obs. in Italy, 2 in MPECs 2018-W65 & 2018-W67 -- 2018 WH1, 2018 WE1
587Sormano Obs. in Italy, 2 in MPECs 2018-W65 & 2018-W67 -- 2018 WH1, 2018 WE1
691Spacewatch 0.9m telescope in Arizona, 4 in MPEC 2018-W69 -- 2018 WP, 2018 VE4, 2018 TO1, 2001 VC2
291Spacewatch 1.8m telescope in Arizona, 14 in MPEC 2018-W69 -- 2018 WU, 2018 WP, 2018 VX8, 2018 VO9, 2018 VO6, 2018 VK10, 2018 VG3, 2018 VE4, 2018 VC, 2018 VB7, 2018 VB1, 2018 VA9, 2009 BJ58, 2004 PS42
W34Squirrel Valley Obs. in North Carolina, 1 in MPEC 2018-W65 -- 2018 WE1
I52Steward Obs. Mt. Lemmon Station in Arizona, 33 in MPECs 2018-W65, 2018-W67, 2018-W68 & 2018-W69 -- 2018 WU, 2018 WP, 2018 WL, 2018 WJ1, 2018 WH1, 2018 WE1, 2018 WB, 2018 VZ9, 2018 VZ1, 2018 VY5, 2018 VX, 2018 VU6, 2018 VT8, 2018 VR4, 2018 VP8, 2018 VN5, 2018 VM6, 2018 VG10, 2018 VF6, 2018 VF3, 2018 VD8, 2018 VB1, 2018 VA9, 2018 TW, 2018 TS, 2018 TN6, 2018 RV5, 2018 RM2, 2018 LO6, 2018 KG1, 2018 KE3, 2017 KE35, 2015 WY1
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2018-W69 -- 1998 HK49
K41Vegaquattro Obs. in Italy, 3 in MPECs 2018-W65 & 2018-W69 -- 2018 WE1, 2018 VX6, 2012 GS5
C51WISE in Earth polar orbit, 1 in MPEC 2018-W66 -- 2018 WD1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 28 November '18

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2358 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
2018 WH1JPL Sentry17302067-2113171.328197e-05-6.91-7.570JPL: Computed at 05:11 today Pacific time based on 39 observations spanning 1.0321 days (2018-Nov-27.25828 to 2018-Nov-28.29033). Diameter approximately 0.007 km. from weighted mean H=28.46.
NEODyS17302067-2113219.98e-06-7.04-7.460NEODyS: "Based on 40 optical observations (of which 1 are rejected as outliers) from 2018-11-27.259 to 2018-11-28.291."
2018 WE1NEODyS17302063-210287.05e-07-6.66-7.030NEODyS: "Based on 44 optical observations (of which 1 are rejected as outliers) from 2018-11-26.470 to 2018-11-27.932."
JPL Sentry05022071-207112.597e-07-7.07-7.070JPL: Computed at 20:37 Nov. 27th Pacific time based on 43 observations spanning 1.4625 days (2018-Nov-26.46885 to 2018-Nov-27.93133). Diameter approximately 0.022 km. from weighted mean H=25.95.
2018 WPNEODyS1730209811.72e-07-4.41-4.410NEODyS: "Based on 30 optical observations (of which 0 are rejected as outliers) from 2018-11-17.398 to 2018-11-27.505."
2018 VO9JPL Sentry17302102-2110150.00013637591-5.28-5.780JPL: Computed at 07:22 today Pacific time based on 22 observations spanning 18.928 days (2018-Nov-09.26967 to 2018-Nov-28.1976). Diameter approximately 0.014 km. from weighted mean H=26.92.
NEODyS17302102-2115201.61e-05-6.22-6.590NEODyS: "Based on 22 optical observations (of which 0 are rejected as outliers) from 2018-11-09.270 to 2018-11-28.198."
2018 VO6JPL Sentry1730R E M O V E DJPL: Risk listing removed at 1525 UTC today
NEODyS1730204811.47e-07-6.26-6.260NEODyS: "Based on 56 optical observations (of which 0 are rejected as outliers) from 2018-11-05.411 to 2018-11-28.301."
2018 VCJPL Sentry17302109-211889.47e-06-6.13-6.410JPL: Computed at 07:14 today Pacific time based on 134 observations spanning 27.136 days (2018-Nov-01.24873 to 2018-Nov-28.38492). Diameter approximately 0.018 km. from weighted mean H=26.32.
NEODyS17302107-2118196.22e-06-6.33-6.53-NEODyS: "Based on 134 optical observations (of which 0 are rejected as outliers) from 2018-11-01.250 to 2018-11-28.386."

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 28 November '18

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

2010Generated Traffic Report
1730Noted that JPL Sentry has updated its 2018 VC risk assessment - see above
Noted that NEODyS has updated its 2018 VC risk assessment - see above
Noted that JPL Sentry has removed 2018 VO6 as an impact risk - see above
Noted that NEODyS has updated its 2018 VO6 risk assessment - see above
Noted that JPL Sentry has updated its 2018 VO9 risk assessment - see above
Noted that NEODyS has updated its 2018 VO9 risk assessment - see above
Noted that NEODyS has posted 2018 WE1 as an impact risk - see above
Noted that JPL Sentry has posted 2018 WH1 as an impact risk - see above
Noted that NEODyS has posted 2018 WH1 as an impact risk - see above
Noted that NEODyS has updated its 2018 WP risk assessment - see above
Grabbed MPEC 2018-W67 - 2018 WH1 - see above
Grabbed MPEC 2018-W68 - 2018 WJ1 - see above
Grabbed MPEC 2018-W69 - Daily Orbit Update - see above
0502Noted that JPL Sentry has posted 2018 WE1 as an impact risk - see above
Grabbed MPEC 2018-W65 - 2018 WE1 - see above
Grabbed MPEC 2018-W66 - 2018 WD1 - see above