Contents  on 5 December '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 5 December '18

Fourteen objects reported inside ten LD

Fourteen small celestial objects are reported flying within ten lunar distances (LD) of Earth today. Closest of these is risk-listed intruder 2018 WV1, which remains inside our planet's sphere of gravitaional influence as it travels outward from 1.53 to 1.96 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
0.09 LD Dec. 2 2018 WV1 3 m  1.53 to 1.96 LD Nov. 8 - Dec. 25 intruder, NHATS target, inside Earth SOI, risk - DOU
0.52 LD Nov. 30 2018 WG2 3 m  6.18 to 7.64 LD Nov. 23 - Dec. 7 intruder, NHATS target, risk
1.18 LD Nov. 25 2018 WH1 7 m  8.38 to 9.29 LD Nov. 15 - tomorrow Moon buzzer, NHATS target, risk
2.06 LD Dec. 3 2018 XB 7 m  2.83 to 3.91 LD Nov. 26 - Dec. 10 NEW, NHATS target - MPEC
2.62 LD Dec. 15 2018 VO9 14 m  6.47 from 7.03 LD Nov. 29 - Dec. 31 NHATS target, risk
2.76 LD Dec. 1 2018 WF2 7 m  9.36 to 11.83 LD Nov. 27 - today exits ten LD
3.42 LD yesterday 2018 WD2 21 m  3.42 to 3.91 LD Nov. 29 - Dec. 10
3.77 LD Dec. 7 2018 XG 16 m  4.61 from 6.03 LD Dec. 2 - 11 NEW - MPEC, DOU
3.92 LD Dec. 2 2018 TG6 12 m  3.98 to 4.03 LD Oct. 30 - Jan. 5 NHATS target
4.1   LD Dec. 9* 2013 VX4 62 m  6.9 from 8.1 LD Dec. 3 - 15 EPU +/- 2.35 days*
4.82 LD Dec. 7 2018 WX1 52 m  5.57 from 6.81 LD Dec. 3 - 11 NHATS target - DOU
5.71 LD Dec. 1 2018 XE 31 m  8.59 to 10.06 LD Nov. 27 - today NEW, NHATS target, exits ten LD - MPEC, DOU
7.84 LD Dec. 2 2018 XF 25 m  9.29 to 10.63 LD Nov. 29 - today NEW, exits ten LD - MPEC
8.21 LD Nov. 25 2018 VT7 9 m  9.43 to 9.67 LD Nov. 15 - Dec. 7 NHATS target
* EPU = Earth passage uncertainty

This report was generated at 1850 UTC with the discovery of just departed 2018 XJ (MPEC), which flew by us at 5.76 LD on November 30th, and with six discoveries announced late yesterday -- inbound 2018 XG (MPEC, DOU), outbound objects 2018 XB (MPEC), 2018 XE (MPEC, DOU), and 2018 XF (MPEC), and departed objects 2018 XC (MPEC) and risk-listed intruder 2018 WA3 (MPEC), which went by at 0.84 LD on November 28th. Today's DOU MPEC has follow-up for approaching 2001 XG1, inbound 2018 WX1, outbound risk-listed intruder 2018 WV1, departed 2008 WS62, and departed risk-listed objects 2018 XA and intruder 2018 WE1.

Approaching - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
7.84 LD Dec. 10 2001 XG1 74 m  15.21 from 18.04 LD Dec. 8 - 12 DOU
7.36 LD Dec. 22 163899 2003 SD220 1.17 km  23.20 from 24.46 LD Dec. 17 - 26 radar/NHATS target
7.3   LD Jan. 9* 2013 YM2 19 m  34.0 from 35.0 LD Jan. 2 - 16 EPU +/- 1.25 days*, NHATS target



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 5 December '18

The MPC's NEO Confirmation Page has 36 listings

When last checked at 2355 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 36 objects listed. Of these, 20 were "one nighters." So far The Tracking News has counted a total of 47 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 5 December '18

Minor Planet Electronic Circulars

As of last check at 2351 UTC, there have been four MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2018-X44 - "15:49 UT" - 2018 XJ


MPEC 2018-X43 - "15:45 UT" - 2018 XH


<< DOU on 5 Dec. '18 >>  MPEC 2018-X42 - "13:05 UT" - Daily Orbit Update


MPEC 2018-X41 - "12:29 UT" - 2015 JV

Observers  on 5 December '18

A total of 27 observers appear in today's MPECs.

CodeObserver / observatory
T05ATLAS Haleakala in Hawaii, 2 in MPEC 2018-X42 -- 2010 AK, 2001 XG1
T08ATLAS Mauna Loa in Hawaii, 3 in MPEC 2018-X42 -- 2018 RL, 2017 BP5, 2010 GT7
160Castelmartini Obs. in Italy, 4 in MPEC 2018-X42 -- 2003 NW1, 36284, 154656, 12711
703Catalina Sky Survey in Arizona, 1 in MPEC 2018-X42 -- 2011 XE1
J04ESA Optical Ground Station (ESA OGS) in the Canary Islands, 6 in MPECs 2018-X42, 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH, 2018 XG, 2018 XE, 2018 WV1, 2015 YU7
K88GINOP-KHK in Hungary, 1 in MPEC 2018-X43 -- 2018 XH
J95Great Shefford Obs. in England, 1 in MPEC 2018-X43 -- 2018 XH
W87LCO Cerro Tololo C in Chile, 1 in MPEC 2018-X42 -- 2018 WV1
K38M57 Obs. in Italy, 2 in MPEC 2018-X42 -- 2018 WX1, 2018 GX4
H01Magdalena Ridge Obs. (MRO) in New Mexico, 3 in MPECs 2018-X41, 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH, 2015 JV
Z22MASTER IAC Obs. in the Canary Islands, 1 in MPEC 2018-X42 -- 88263
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2018-X41 & 2018-X44 -- 2018 XJ, 2015 JV
Z80Northolt Branch Obs. in England, 2 in MPEC 2018-X42 -- 2002 VE68, 523815
I41Palomar Transient Factory (PTF) in southern California, 3 in MPEC 2018-X42 -- 2010 TJ54, 455550, 244670
K63Pascoli Obs. in Italy, 1 in MPEC 2018-X43 -- 2018 XH
A53Peschiera del Garda Obs. in Italy, 2 in MPEC 2018-X42 -- 2018 QN1, 2018 GX4
104San Marcello Pistoiese Obs. in Italy, 3 in MPECs 2018-X42, 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH, 2018 WX2
C95SATINO-1 in France, 1 in MPEC 2018-X42 -- 2001 XG1
204Schiaparelli Obs. in Italy, 2 in MPECs 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH
033Schwarzschild Obs. in Germany, 2 in MPECs 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH
G409B. Lutkenhoner in Germany via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2018-X42 -- 2018 XA
587Sormano Obs. in Italy, 1 in MPEC 2018-X43 -- 2018 XH
691Spacewatch 0.9m telescope in Arizona, 4 in MPEC 2018-X42 -- 2018 XA, 2018 VZ8, 2018 VN3, 2015 YU7
291Spacewatch 1.8m telescope in Arizona, 2 in MPEC 2018-X42 -- 2018 WE1, 2008 WS62
I52Steward Obs. Mt. Lemmon Station in Arizona, 16 in MPECs 2018-X41, 2018-X42, 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH, 2018 WX1, 2018 WU1, 2018 WP2, 2018 WO2, 2018 WM2, 2018 WH2, 2018 VY5, 2018 VV1, 2018 VT3, 2018 VM3, 2018 VA10, 2018 UZ, 2015 YU7, 2015 JV
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2018-X42 -- 2017 EB3
L01Visnjan Obs., 3 in MPECs 2018-X41, 2018-X43 & 2018-X44 -- 2018 XJ, 2018 XH, 2015 JV
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 5 December '18

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2351 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 XAJPL Sentry16402099-209923.201e-07-5.92-6.080JPL: Computed at 07:10 today Pacific time based on 84 observations spanning 3.8304 days (2018-Dec-01.34686 to 2018-Dec-05.17728). Diameter approximately 0.068 km. from weighted mean H=23.50.
2018 WE1JPL Sentry16402063-210251.07801e-06-6.45-6.720JPL: Computed at 07:14 today Pacific time based on 69 observations spanning 8.7015 days (2018-Nov-26.46885 to 2018-Dec-05.17033). Diameter approximately 0.022 km. from weighted mean H=25.95.

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 5 December '18

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

1850Generated Traffic Report
1640Noted that JPL Sentry has updated its 2018 WE1 risk assessment - see above
Noted that JPL Sentry has updated its 2018 XA risk assessment - see above
Grabbed MPEC 2018-X41 - 2015 JV - see above
Grabbed MPEC 2018-X42 - Daily Orbit Update - see above
Grabbed MPEC 2018-X43 - 2018 XH - see above
Grabbed MPEC 2018-X44 - 2018 XJ - see above