Contents  on 27 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 27 December '18

Five objects reported inside ten LD

Five minor planets are reported within ten lunar distances (LD) of Earth today, none of them closer thant 4.35 LD (outbound risk-listed 2018 XN5).

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
1.60 LD Dec. 21 2018 XC4 20 m  9.42 to 11.14 LD Dec. 15 - 27 NHATS target, exits ten LD
2.62 LD Dec. 15 2018 VO9 14 m  7.66 to 8.24 LD Nov. 29 - Dec. 31 NHATS target, risk
2.96 LD Dec. 24 2018 XN5 28 m  4.35 to 5.48 LD Dec. 18 - 31 NHATS target, risk
3.92 LD Dec. 2 2018 TG6 12 m  7.85 to 8.09 LD Oct. 30 - Jan. 5 NHATS target
5.3   LD yesterday* 2018 XE4 17 m  5.3 to 5.9 LD Dec. 22 - 30 EPU +/- 3.33 hours*
* EPU = Earth passage uncertainty

This report was generated at 1815 UTC with follow-up for distant 68216 2001 CV26 in today's DOU MPEC.

Approaching - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
7.8   LD Jan. 6* 2018 XO4 30 m  11.8 from 12.4 LD Dec. 30 - Jan. 13 EPU +/- 17 mins.*, NHATS target
7.3   LD Jan. 9* 2013 YM2 19 m  14.2 from 15.0 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. "Distant" is used here to describe an object that has approached Earth within ten LD since A/CC began these traffic reports eleven-plus years ago but is not currently coming so close. 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 27 December '18

The MPC's NEO Confirmation Page has 9 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had nine objects listed. Of these, three were "one nighters." So far The Tracking News has counted a total of twelve 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 27 December '18

Minor Planet Electronic Circulars

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


MPEC 2018-Y83 - "19:48 UT" - 2018 AP18


MPEC 2018-Y82 - "19:46 UT" - 2017 AF5


MPEC 2018-Y81 - "19:44 UT" - 2013 BG27


MPEC 2018-Y80 - "18:44 UT" - 2018 YF2


MPEC 2018-Y79 - "18:31 UT" - 2018 YE2


<< DOU on 27 Dec. '18 >>  MPEC 2018-Y78 - "13:06 UT" - Daily Orbit Update


MPEC 2018-Y77 - "04:07 UT" - 2017 VB


MPEC 2018-Y76 - "01:57 UT" - 2017 MK8


MPEC 2018-Y75 - "01:16 UT" - 2014 WM509

Observers  on 27 December '18

Sixteen observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 9 in MPECs 2018-Y78 & 2018-Y80 -- 2018 YF2, 2018 XY5, 2018 VN5, 2018 VH1, 2018 VG10, 2018 RM2, 2018 NS3, 2016 JN34, 2014 QO296
T08ATLAS Mauna Loa in Hawaii, 2 in MPEC 2018-Y78 -- 2014 JU54, 2009 SV17
160Castelmartini Obs. in Italy, 18 in MPEC 2018-Y78 -- 2018 XZ2, 2018 XB2, 2018 WR1, 2010 GT7, 2003 NW1, 68216, 523604, 450238, 418849, 36284, 345722, 345705, 217807, 18109, 154656, 136793, 4401, 1916
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 2 in MPECs 2018-Y79 & 2018-Y81 -- 2018 YE2, 2013 BG27
G37Discovery Channel Telescope in Arizona, 1 in MPEC 2018-Y75 -- 2014 WM509
595Farra d'Isonzo Obs. in Italy, 1 in MPEC 2018-Y80 -- 2018 YF2
K88GINOP-KHK in Hungary, 1 in MPEC 2018-Y79 -- 2018 YE2
K38M57 Obs. in Italy, 4 in MPEC 2018-Y78 -- 2018 XZ4, 2018 XV, 2018 XC2, 2018 XB2
C23Olmen Obs. in Belgium, 4 in MPEC 2018-Y78 -- 2007 YQ56, 2004 XP14, 2003 NW1, 418849
F51Pan-STARRS 1 (PS1) in Hawaii, 14 in MPECs 2018-Y75, 2018-Y76, 2018-Y77, 2018-Y78, 2018-Y80, 2018-Y82 & 2018-Y83 -- 2018 YF2, 2018 KV, 2018 AP18, 2017 XD, 2017 VB, 2017 MK8, 2017 HW1, 2017 AF5, 2016 GT220, 2016 ED85, 2015 FP332, 2015 AS45, 2014 WM509, 2002 BJ2
104San Marcello Pistoiese Obs. in Italy, 3 in MPECs 2018-Y78, 2018-Y79 & 2018-Y80 -- 2018 YF2, 2018 YE2, 2009 SV17
233San Vito Obs. in Italy, 3 in MPEC 2018-Y78 -- 2003 NW1, 3552, 1627
C95SATINO-1 in France, 3 in MPECs 2018-Y78 & 2018-Y80 -- 2018 YF2, 3288, 3199
291Spacewatch 1.8m telescope in Arizona, 1 in MPEC 2018-Y80 -- 2018 YF2
L01Visnjan Obs., 2 in MPECs 2018-Y79 & 2018-Y80 -- 2018 YF2, 2018 YE2
C51WISE in Earth polar orbit, 1 in MPEC 2018-Y79 -- 2018 YE2
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 27 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
2008 EL68JPL Sentry19012019-21136073.24469073e-05-5.39-6.210JPL: Computed at 11:57 April 9th of 2017 Pacific time based on 8 observations spanning .07124 days (2008-Mar-06.40768 to 2008-Mar-06.47892). Diameter approximately 0.009 km. from weighted mean H=27.92.

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 27 December '18

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

2000Grabbed MPEC 2018-Y81 - 2013 BG27 - see above
Grabbed MPEC 2018-Y82 - 2017 AF5 - see above
Grabbed MPEC 2018-Y83 - 2018 AP18 - see above
1901Noted that JPL Sentry has updated its 2008 EL68 risk assessment - see above
Grabbed MPEC 2018-Y79 - 2018 YE2 - see above
Grabbed MPEC 2018-Y80 - 2018 YF2 - see above
1815Generated Traffic Report
1800Grabbed MPEC 2018-Y78 - Daily Orbit Update - see above
0500Grabbed MPEC 2018-Y75 - 2014 WM509 - see above
Grabbed MPEC 2018-Y76 - 2017 MK8 - see above
Grabbed MPEC 2018-Y77 - 2017 VB - see above