Contents  on 30 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 30 December '18

Seven objects reported inside ten LD

Seven asteroids are reported to be within ten lunar distances (LD) of our home world today. Nearest are newly announced risk-listed intruder 2018 YL2, heading out from 5.81 to 8.36 LD, and just discovered 2018 YM2, moving in from 6.94 to 6.41 LD.

Neighborhood Traffic - sorted by Earth passage distance, grouped by 1.0, 5.0 & 10.0 LD boundaries
Earth passage I D ~Size Distance today  Inside ten LD Notes
0.15 LD Dec. 27 2018 YL2 5 m  5.81 to 8.36 LD Dec. 23 - 31 NEW, intruder, risk - MPEC
2.62 LD Dec. 15 2018 VO9 14 m  9.39 to 9.96 LD Nov. 29 - tomorrow NHATS target, risk
2.96 LD Dec. 24 2018 XN5 28 m  8.01 to 9.33 LD Dec. 18 - 31 NHATS target, risk
3.92 LD Dec. 2 2018 TG6 12 m  8.57 to 8.81 LD Oct. 30 - Jan. 5 NHATS target
5.3   LD Dec. 26* 2018 XE4 17 m  8.5 to 10.2 LD Dec. 22 - 30 EPU +/- 3.33 hours*, exits ten LD
6.41 LD tomorrow 2018 YM2 41 m  6.41 from 6.94 LD Dec. 28 - Jan. 3 NEW - MPEC
7.8   LD Jan. 6* 2018 XO4 30 m  10.0 from 10.5 LD today - Jan. 13 EPU +/- 17 mins.*, NHATS target, enters ten LD
* EPU = Earth passage uncertainty

This report was generated at 2105 UTC with the discoveries of risk-listed intruder 2018 YL2 (MPEC), which passed us at 0.15 LD and the Moon at 0.51 LD on December 27th, inbound 2018 YM2 (MPEC), and alredy departed 2018 YK2 (MPEC), which went by at 8.01 LD on December 23rd.

Approaching
Earth passage I D ~Size Distance today  Inside ten LD Notes
7.3   LD Jan. 9* 2013 YM2 19 m  11.8 from 12.6 LD Jan. 2 - 16 EPU +/- 3.75 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. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

NEOCP Activity  on 30 December '18

The MPC's NEO Confirmation Page has 4 listings

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


MPEC 2018-Y97 - "20:13 UT" - 2007 YU56


<< DOU on 30 Dec. '18 >>  MPEC 2018-Y96 - "13:05 UT" - Daily Orbit Update


MPEC 2018-Y95 - "02:33 UT" - 2018 YL2


MPEC 2018-Y94 - "02:10 UT" - 2018 YM2


MPEC 2018-Y93 - "02:07 UT" - 2018 YK2

Observers  on 30 December '18

A total of 30 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 12 in MPEC 2018-Y96 -- 2018 YS, 2018 XZ4, 2018 XV, 2018 XR, 2018 XH, 2018 XC2, 2018 XB2, 2018 XA5, 2018 VW6, 2018 VL7, 2018 VB9, 2018 VA10
T05ATLAS Haleakala in Hawaii, 12 in MPECs 2018-Y93, 2018-Y94, 2018-Y96 & 2018-Y97 -- 2018 YS, 2018 YM2, 2018 YK2, 2018 XY2, 2018 XR, 2018 VZ9, 2018 VW6, 2014 JU54, 2013 PA7, 2009 SV17, 2007 YU56, 418849
T08ATLAS Mauna Loa in Hawaii, 4 in MPECs 2018-Y95 & 2018-Y96 -- 2018 YL2, 2018 XV, 2018 VB9, 523811
C77Bernezzo Obs. in Italy, 3 in MPECs 2018-Y93, 2018-Y94 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2007 YU56
160Castelmartini Obs. in Italy, 5 in MPECs 2018-Y96 & 2018-Y97 -- 2007 YU56, 138937, 137084, 6178, 5131
Z99Clixby Obs. in England, 3 in MPECs 2018-Y93, 2018-Y94 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2007 YU56
595Farra d'Isonzo Obs. in Italy, 3 in MPECs 2018-Y93, 2018-Y94 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2007 YU56
E89Geyserland Obs. in New Zealand, 5 in MPEC 2018-Y96 -- 99799, 96536, 21277, 180186, 719
K88GINOP-KHK in Hungary, 4 in MPECs 2018-Y93, 2018-Y94, 2018-Y95 & 2018-Y97 -- 2018 YM2, 2018 YL2, 2018 YK2, 2007 YU56
J95Great Shefford Obs. in England, 5 in MPECs 2018-Y93, 2018-Y96 & 2018-Y97 -- 2018 YK2, 2018 YJ2, 2018 XZ2, 2018 XD5, 2007 YU56
Q62`Steven M. Tilley in Louisiana via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2018-Y96 -- 2013 LH16
P93JAXA Space Tracking & Communications Center (JAXA STCC) in Japan, 3 in MPECs 2018-Y93, 2018-Y94 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2007 YU56
Z43Landehen Obs., 1 in MPEC 2018-Y96 -- 99799
K38M57 Obs. in Italy, 4 in MPECs 2018-Y93, 2018-Y94, 2018-Y96 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2018 YJ2, 2007 YU56
G96Mt. Lemmon Survey in Arizona, 1 in MPEC 2018-Y96 -- 2015 FD415
I41Palomar Transient Factory in southern California, 1 in MPEC 2018-Y94 -- 2018 YM2
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPECs 2018-Y93 & 2018-Y96 -- 2018 YK2, 2015 FD415
B49Paus Obs. in Spain, 2 in MPECs 2018-Y93 & 2018-Y97 -- 2018 YK2, 2007 YU56
104San Marcello Pistoiese Obs. in Italy, 4 in MPECs 2018-Y93, 2018-Y94, 2018-Y96 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2007 YU56, 523779
H36Sandlot Obs. in Kansas, 2 in MPECs 2018-Y93 & 2018-Y97 -- 2018 YK2, 2007 YU56
C95SATINO-1 in France, 1 in MPEC 2018-Y96 -- 3288
204Schiaparelli Obs. in Italy, 21 in MPECs 2018-Y93, 2018-Y94, 2018-Y96 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2018 XZ1, 2018 XK1, 2018 XH1, 2018 XD, 2018 XB4, 2018 WX2, 2018 WU1, 2018 WP2, 2018 WO2, 2018 VZ9, 2018 VS9, 2018 TS, 2018 TP2, 2013 BT18, 2013 BE19, 2012 MS4, 2007 YU56, 2007 UL12, 2002 VE68
G403Tony Evans in Portugal via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2018-Y96 -- 2018 VZ9
G409B. Lutkenhoner in Germany via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2018-Y93 -- 2018 YK2
W88!program code "!" (10) via Slooh.com Chile Obs. in Chile, 1 in MPEC 2018-Y96 -- 2013 LH16
587Sormano Obs. in Italy, 3 in MPECs 2018-Y93, 2018-Y94 & 2018-Y97 -- 2018 YM2, 2018 YK2, 2007 YU56
291Spacewatch 1.8m telescope in Arizona, 11 in MPEC 2018-Y96 -- 2018 YZ1, 2018 YZ, 2018 YJ, 2018 XV5, 2018 XH, 2018 XG5, 2018 XB4, 2018 WR1, 2018 WP2, 2018 WE3, 2005 GE60
I52Steward Obs. Mt. Lemmon Station in Arizona, 1 in MPEC 2018-Y96 -- 2018 XS3
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 2 in MPEC 2018-Y96 -- 2018 VR, 2018 TR1
L01Visnjan Obs., 4 in MPECs 2018-Y93, 2018-Y94, 2018-Y95 & 2018-Y97 -- 2018 YM2, 2018 YL2, 2018 YK2, 2007 YU56
J08Zonalunar Obs. in Spain, 1 in MPEC 2018-Y93 -- 2018 YK2
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 30 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.
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 YL2NEODyS2000208611.97e-09-10.94-10.940NEODyS: "Based on 15 optical observations (of which 0 are rejected as outliers) from 2018-12-28.513 to 2018-12-29.917."
2018 YH2NEODyS20002031-2113412.91e-08-6.46-7.030NEODyS: "Based on 6 optical observations (of which 0 are rejected as outliers) from 2018-12-17.620 to 2018-12-18.403."
2018 YZ1NEODyS2358211811.07e-10-6.97-6.97-NEODyS: "Based on 19 optical observations (of which 0 are rejected as outliers) from 2018-12-20.633 to 2018-12-30.480."
JPL Sentry20002118-211811.656e-10-6.90-6.900JPL: Computed at 08:01 today Pacific time based on 19 observations spanning 9.8467 days (2018-Dec-20.63258 to 2018-Dec-30.47931). Diameter approximately 0.670 km. from weighted mean H=18.51.
2018 YJNEODyS2000R E M O V E D-
2018 XG5NEODyS2358208312.21e-07-4.47-4.470NEODyS: "Based on 35 optical observations (of which 0 are rejected as outliers) from 2018-12-13.395 to 2018-12-30.212."
JPL Sentry20002083-208324.1493e-07-4.18-4.200JPL: Computed at 07:51 today Pacific time based on 35 observations spanning 16.817 days (2018-Dec-13.39431 to 2018-Dec-30.21137). Diameter approximately 0.300 km. from weighted mean H=20.28.
2018 XB4NEODyS23582052-2118896.31e-05-4.00-4.36-NEODyS: "Based on 34 optical observations (of which 0 are rejected as outliers) from 2018-12-13.344 to 2018-12-30.271."
JPL Sentry20002052-2118456.26319402e-05-3.98-4.280JPL: Computed at 08:00 today Pacific time based on 34 observations spanning 16.926 days (2018-Dec-13.34358 to 2018-Dec-30.27005). Diameter approximately 0.055 km. from weighted mean H=23.94.
2016 AZ193JPL Sentry20002018-21144992.1978274e-06-6.29-7.220JPL: Computed at 14:28 April 6th of 2017 Pacific time based on 9 observations spanning .15930 days (2016-Jan-03.25638 to 2016-Jan-03.41568). Diameter approximately 0.016 km. from weighted mean H=26.62.

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 30 December '18

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

2358Noted that NEODyS has updated its 2018 XB4 risk assessment - see above
Noted that NEODyS has updated its 2018 XG5 risk assessment - see above
Noted that NEODyS has updated its 2018 YZ1 risk assessment - see above
2105Generated Traffic Report
2050Grabbed MPEC 2018-Y97 - 2007 YU56 - see above
2000Noted that JPL Sentry has updated its 2016 AZ193 risk assessment - see above
Noted that JPL Sentry has updated its 2018 XB4 risk assessment - see above
Noted that JPL Sentry has updated its 2018 XG5 risk assessment - see above
Noted that NEODyS has posted 2018 YH2 as an impact risk - see above
Noted that NEODyS has removed 2018 YJ as an impact risk - see above
Noted that NEODyS has posted 2018 YL2 as an impact risk - see above
Noted that JPL Sentry has updated its 2018 YZ1 risk assessment - see above
Grabbed MPEC 2018-Y96 - Daily Orbit Update - see above
0434Grabbed MPEC 2018-Y93 - 2018 YK2 - see above
Grabbed MPEC 2018-Y94 - 2018 YM2 - see above
Grabbed MPEC 2018-Y95 - 2018 YL2 - see above