Contents  on 7 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 7 December '18

Ten objects reported inside ten LD

Ten minor objects are reported less than ten lunar distances (LD) from Earth today. Intruder 2018 WV1 is the nearest, exiting our planet's sphere of gravitational influence as it travels out from 2.39 to 2.81 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  2.39 to 2.81 LD Nov. 8 - Dec. 25 intruder, NHATS target, exits Earth SOI - DOU
0.52 LD Nov. 30 2018 WG2 3 m  9.10 to 10.57 LD Nov. 23 - today intruder, NHATS target, exits ten LD, risk
2.06 LD Dec. 3 2018 XB 7 m  5.13 to 6.41 LD Nov. 26 - Dec. 10 NHATS target
2.62 LD Dec. 15 2018 VO9 14 m  5.37 from 5.91 LD Nov. 29 - Dec. 31 NHATS target, risk
3.42 LD Dec. 4 2018 WD2 21 m  4.96 to 6.30 LD Nov. 29 - Dec. 10
3.77 LD today 2018 XG 16 m  3.77 LD Dec. 2 - 11 Earth closest at 0650 UTC
3.92 LD Dec. 2 2018 TG6 12 m  4.10 to 4.19 LD Oct. 30 - Jan. 5 NHATS target
4.1   LD Dec. 9* 2013 VX4 62 m  4.8 from 5.7 LD Dec. 3 - 15 EPU +/- 2.35 days*
4.82 LD today 2018 WX1 52 m  4.82 LD Dec. 3 - 11 NHATS target, Earth closest at 0908 UTC
8.21 LD Nov. 25 2018 VT7 9 m  9.94 to 10.21 LD Nov. 15 - today NHATS target, exits ten LD
* EPU = Earth passage uncertainty

This report was generated at 1910 UTC with follow-up in today's DOU MPEC for 2008 WD14 and two risk-listed intruders: outbound 2018 WV1 and departed 2018 WA3, plus observation of 2018 SC1 from October, adding 12.09 days to its 4.21-day observing arc.

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  10.27 from 12.57 LD tomorrow - Dec. 12
7.36 LD Dec. 22 163899 2003 SD220 1.17 km  20.68 from 21.94 LD Dec. 17 - 26 radar/NHATS target
7.3   LD Jan. 9* 2013 YM2 19 m  32.2 from 33.1 LD Jan. 2 - 16 EPU +/- 1.25 days*, NHATS target

<< Reading:  A new science paper PDF presents evidence that the destruction of Sodom and Gomorrah as told in Genesis was an actual event caused by an enormous atmospheric impact. Universe Today has a report.

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 7 December '18

The MPC's NEO Confirmation Page has 28 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 28 objects listed. Of these, fifteen were "one nighters." So far The Tracking News has counted a total of 30 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 7 December '18

Minor Planet Electronic Circulars

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

<< DOU on 7 Dec. '18 >>  MPEC 2018-X52 - "13:07 UT" - Daily Orbit Update

Observers  on 7 December '18

Seven observers appear in today's MPEC.

CodeObserver / observatory
T08ATLAS Mauna Loa in Hawaii, 1 in MPEC 2018-X52 -- 2008 WD14
160Castelmartini Obs. in Italy, 7 in MPEC 2018-X52 -- 2018 GX4, 2001 VC2, 414960, 36284, 208617, 18109, 12711
J04ESA Optical Ground Station in the Canary Islands, 1 in MPEC 2018-X52 -- 2015 UT52
W85LCO Cerro Tololo A in Chile, 1 in MPEC 2018-X52 -- 2018 WV1
474Mt. John Obs. in New Zealand, 3 in MPEC 2018-X52 -- 2018 XD, 2018 VB4, 2015 FB35
C95SATINO-1 in France, 1 in MPEC 2018-X52 -- 2014 XR6
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 6 in MPEC 2018-X52 -- 2018 WV1, 2018 WA3, 2018 VN5, 2018 SC1, 2018 RU5, 2006 WR127
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 7 December '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.





Notes for Today's Latest Risk Assessments
2018 XANEODyS16372099-211631.31e-06-5.32-5.480NEODyS: "Based on 86 optical observations (of which 0 are rejected as outliers) from 2018-12-01.348 to 2018-12-05.519."
2018 WA3JPL Sentry16372055-206022.88942e-06-6.63-6.630JPL: Computed at 07:33 today Pacific time based on 26 observations spanning 7.1321 days (2018-Nov-29.26148 to 2018-Dec-06.393599). Diameter approximately 0.009 km. from weighted mean H=27.83.
NEODyS16372055-206021.15e-05-6.03-6.040NEODyS: "Based on 24 optical observations (of which 0 are rejected as outliers) from 2018-11-29.262 to 2018-12-03.003."
2018 WV1NEODyS1637R E M O V E D-
2018 WH1NEODyS16372067-2117281.95e-05-6.72-7.150NEODyS: "Based on 58 optical observations (of which 1 are rejected as outliers) from 2018-11-27.259 to 2018-12-04.224."
2018 WE1NEODyS16372063-210261.22e-06-6.41-6.870NEODyS: "Based on 71 optical observations (of which 2 are rejected as outliers) from 2018-11-26.470 to 2018-12-05.171."
2018 WJNEODyS16372045-207587.92e-07-7.00-7.370NEODyS: "Based on 81 optical observations (of which 0 are rejected as outliers) from 2018-11-17.268 to 2018-11-19.910."
2018 VO9NEODyS16372102-2110148.35e-06-6.53-6.720NEODyS: "Based on 29 optical observations (of which 0 are rejected as outliers) from 2018-11-09.270 to 2018-12-04.073."
2018 TP5NEODyS16372074-2113591.8e-05-5.27-5.930NEODyS: "Based on 38 optical observations (of which 0 are rejected as outliers) from 2018-10-10.316 to 2018-12-03.051."
2016 JT38NEODyS16372078-210342.35e-07-4.32-4.680NEODyS: "Based on 18 optical observations (of which 0 are rejected as outliers) from 2016-04-26.315 to 2016-05-05.307."

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 7 December '18

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

1910Generated Traffic Report
1637Noted that NEODyS has updated its 2016 JT38 risk assessment - see above
Noted that NEODyS has updated its 2018 TP5 risk assessment - see above
Noted that NEODyS has updated its 2018 VO9 risk assessment - see above
Noted that JPL Sentry has updated its 2018 WA3 risk assessment - see above
Noted that NEODyS has posted 2018 WA3 as an impact risk - see above
Noted that NEODyS has updated its 2018 WE1 risk assessment - see above
Noted that NEODyS has updated its 2018 WH1 risk assessment - see above
Noted that NEODyS has updated its 2018 WJ risk assessment - see above
Noted that NEODyS has removed 2018 WV1 as an impact risk - see above
Noted that NEODyS has posted 2018 XA as an impact risk - see above
Grabbed MPEC 2018-X52 - Daily Orbit Update - see above