Contents  on 27 December '17

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 '17

Eleven objects reported inside ten LD

Today there are eleven planetesimals reported within ten lunar distances (LD) of our planet. Nearest are intruder 2017 YZ4, which enters Earth's SOI, coming in from 3.6 to 1.5 LD, and risk-listed 2017 YD2, which comes its closest to Earth this time around, reaching 2.24 LD at 0239 UTC, and also its closest to the Moon -- 1.37 LD at 0651 UTC.

Earth passage I D ~Size Distance today  Inside ten LD Notes
0.6   LD tomorrow* 2017 YZ4 9 m  1.5 from 3.6 LD Dec. 23 - Jan. 2 EPU +/- 6 mins.*, intruder, NHATS target,
enters Earth SOI
1.43 LD Dec. 21 2017 YO5 22 m  8.42 to 10.04 LD Dec. 15 - 27 NEW, exits ten LD, risk - MPEC
1.77 LD Dec. 15 2017 YD1 3 m  7.41 to 8.04 LD Nov. 30 - Dec. 31 NHATS target, risk
1.93 LD Dec. 24 2017 YS1 6 m  2.58 to 3.11 LD Dec. 11 - Jan. 7 NHATS target
2.24 LD today 2017 YD2 6 m  2.24 LD Dec. 21 - Jan. 1 NHATS target, Earth closest at 0239 UTC,
Moon closest 1.37 LD at 0651 UTC, risk
2.88 LD Dec. 22 2017 YE 7 m  5.64 to 6.56 LD Dec. 13 - 31 NHATS target
4.84 LD Dec. 19 2017 YW3 17 m  6.77 to 7.25 LD Dec. 5 - Jan. 1 NHATS target - DOU
5.13 LD yesterday 2017 YQ1 41 m  5.54 to 8.55 LD Dec. 24 - 28
7.62 LD Dec. 24 2017 WZ14 32 m  7.96 to 8.34 LD Dec. 18 - 30 radar/NHATS target
7.74 LD Dec. 30 2017 YU1 20 m  8.68 from 9.58 LD yesterday - Jan. 3 NHATS target - DOU
8.47 LD Dec. 25 2017 YR3 29 m  8.73 to 9.19 LD Dec. 21 - 29 NHATS target
Approaching (sorted by 10-LD bubble entry date)
3.7   LD Feb. 24* 2017 DR109 10 m  124.4 from 127.4 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
3.8   LD March 7* 2017 VR12 272 m  94.8 from 96.4 LD Feb. 28 - March 13 EPU +/- 5 mins.*, radar/NHATS target
* EPU = Earth passage uncertainty

This report was updated at 2306 UTC with the discovery of 2017 YO5 (MPEC). Your first neighborhood asteroid traffic report was generated at 1808 UTC with follow-up in today's DOU MPEC for inbound 2017 YU1, outbound 2017 YW3, and departed 2017 YH1 and 2006 XY, plus astrometry from early this month for 2017 WB.



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 27 December '17

The MPC's NEO Confirmation Page has 94 listings

When last checked at 2206 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 94 objects listed. Of these, 52 were "one nighters." So far The Tracking News has counted a total of 114 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 '17

Minor Planet Electronic Circulars

As of last check at 2342 UTC, there have been fifteen MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2017-Y127 - "20:46 UT" - 2017 YO5


MPEC 2017-Y126 - "20:42 UT" - 2017 YK5


MPEC 2017-Y125 - "20:38 UT" - 2017 YQ5


MPEC 2017-Y124 - "20:34 UT" - 2017 YP5


MPEC 2017-Y123 - "20:30 UT" - 2017 YN5


MPEC 2017-Y122 - "20:26 UT" - 2017 YM5


MPEC 2017-Y121 - "20:22 UT" - 2017 YL5


MPEC 2017-Y120 - "20:19 UT" - 2017 YJ5


MPEC 2017-Y119 - "20:15 UT" - 2017 YH5


MPEC 2017-Y118 - "20:12 UT" - 2017 YG5


MPEC 2017-Y117 - "20:08 UT" - 2017 YF5


MPEC 2017-Y116 - "20:04 UT" - 2017 YE5


<< DOU on 27 Dec. '17 >>  MPEC 2017-Y115 - "13:05 UT" - Daily Orbit Update


MPEC 2017-Y114 - "12:25 UT" - 2017 NS5


MPEC 2017-Y113 - "12:23 UT" - 2002 LX

Observers  on 27 December '17

A total of 33 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 24 in MPECs 2017-Y115, 2017-Y117, 2017-Y119, 2017-Y120, 2017-Y121, 2017-Y122, 2017-Y123, 2017-Y125 & 2017-Y126 -- 2017 YQ5, 2017 YN5, 2017 YM5, 2017 YL5, 2017 YK5, 2017 YJ5, 2017 YH5, 2017 YF5, 2017 WB, 2017 VV1, 2017 VL15, 2017 TC4, 2017 SZ13, 2017 ST19, 2017 SQ14, 2017 SG19, 2017 RL2, 2017 QW17, 2017 PX24, 2007 YZ58, 505093, 486692, 310402, 3360
T05ATLAS Haleakala in Hawaii, 3 in MPECs 2017-Y115 & 2017-Y124 -- 2017 YP5, 1865, 1685
T08ATLAS Mauna Loa in Hawaii, 3 in MPEC 2017-Y115 -- 2017 YX4, 2017 YP4, 2007 XP3
160Castelmartini Obs. in Italy, 11 in MPEC 2017-Y115 -- 96590, 85628, 505667, 415029, 25916, 190208, 162011, 143992, 8567, 1866, 1627
703Catalina Sky Survey (CSS) in Arizona, 4 in MPECs 2017-Y115, 2017-Y126 & 2017-Y127 -- 2017 YO5, 2017 YK5, 2017 QJ18, 495848
V06Catalina Sky Survey Kuiper Telescope in Arizona, 1 in MPEC 2017-Y116 -- 2017 YE5
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. in Chile, 1 in MPEC 2017-Y118 -- 2017 YG5
113Drebach Obs. in Germany, 1 in MPEC 2017-Y126 -- 2017 YK5
K88GINOP-KHK in Hungary, 3 in MPECs 2017-Y121, 2017-Y124 & 2017-Y126 -- 2017 YP5, 2017 YL5, 2017 YK5
J95Great Shefford Obs. in England, 1 in MPEC 2017-Y126 -- 2017 YK5
G48Harlingten Research Obs. in New Mexico, 1 in MPEC 2017-Y115 -- 2017 YH1
C43Hoyerswerda Obs. in Germany, 1 in MPEC 2017-Y126 -- 2017 YK5
246KLENOT in the Czech Republic, 3 in MPECs 2017-Y121, 2017-Y124 & 2017-Y126 -- 2017 YP5, 2017 YL5, 2017 YK5
Z22MASTER IAC Obs. in the Canary Islands, 2 in MPEC 2017-Y115 -- 1999 AF4, 475967
5682David Tholen's team on Mauna Kea in Hawaii, 1 in MPEC 2017-Y115 -- 2016 GF1
568_Marco Micheli on Mauna Kea in Hawaii, 3 in MPECs 2017-Y115, 2017-Y119 & 2017-Y120 -- 2017 YX3, 2017 YJ5, 2017 YH5
711McDonald Obs. in Texas, 6 in MPECs 2017-Y116, 2017-Y117, 2017-Y119, 2017-Y120, 2017-Y124 & 2017-Y126 -- 2017 YP5, 2017 YK5, 2017 YJ5, 2017 YH5, 2017 YF5, 2017 YE5
G96Mt. Lemmon Survey (MLS) in Arizona, 28 in MPECs 2017-Y113, 2017-Y115, 2017-Y121, 2017-Y122 & 2017-Y123 -- 2017 YW3, 2017 YU1, 2017 YN5, 2017 YM5, 2017 YL5, 2017 XN61, 2017 XL2, 2017 TC4, 2015 VC66, 2015 RT1, 2014 WG365, 2002 LX, 89136, 68278, 504887, 500749, 496861, 495858, 306383, 258325, 19764, 190208, 185853, 163373, 153349, 141079, 136839, 8034
K74Muensterschwarzach Obs. in Germany, 3 in MPEC 2017-Y115 -- 2017 YH1, 2017 QL33, 11066
C47Nonndorf Obs. in Austria, 1 in MPEC 2017-Y126 -- 2017 YK5
G34Oberfrauendorf Obs. in Germany, 1 in MPEC 2017-Y126 -- 2017 YK5
J43Oukaimeden Obs. in Morocco, 1 in MPEC 2017-Y116 -- 2017 YE5
F51Pan-STARRS 1 (PS1) in Hawaii, 27 in MPECs 2017-Y115, 2017-Y116, 2017-Y117, 2017-Y118, 2017-Y119, 2017-Y120 & 2017-Y125 -- 2017 YQ5, 2017 YJ5, 2017 YH5, 2017 YG5, 2017 YF5, 2017 YE5, 2017 XO60, 2017 VB, 2017 UW4, 2017 PX24, 2016 AU8, 2015 VO66, 2010 EX119, 2009 BM2, 2009 BL71, 2008 CJ70, 2004 BG86, 2000 BL19, 495960, 465098, 455432, 403247, 177255, 16834, 5496, 3122, 1036
H36Sandlot Obs. in Kansas, 2 in MPECs 2017-Y113 & 2017-Y127 -- 2017 YO5, 2002 LX
G40(program code "(" (17) via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2017-Y124 -- 2017 YP5
691Spacewatch 0.9m telescope in Arizona, 3 in MPEC 2017-Y115 -- 2017 XL2, 2017 XB1, 2006 XY
291Spacewatch 1.8m telescope in Arizona, 5 in MPECs 2017-Y115, 2017-Y117, 2017-Y118, 2017-Y119 & 2017-Y125 -- 2017 YQ5, 2017 YH5, 2017 YG5, 2017 YF5, 2015 VC66
I52Steward Obs. Mt. Lemmon Station in Arizona, 11 in MPECs 2017-Y113, 2017-Y116, 2017-Y117, 2017-Y119, 2017-Y120, 2017-Y121, 2017-Y122, 2017-Y124, 2017-Y125, 2017-Y126 & 2017-Y127 -- 2017 YQ5, 2017 YP5, 2017 YO5, 2017 YM5, 2017 YL5, 2017 YK5, 2017 YJ5, 2017 YH5, 2017 YF5, 2017 YE5, 2002 LX
J22Tacande Obs. in the Canary Islands, 1 in MPEC 2017-Y124 -- 2017 YP5
926Tenagra II Obs. in Arizona, 7 in MPECs 2017-Y119, 2017-Y120, 2017-Y122, 2017-Y123, 2017-Y125, 2017-Y126 & 2017-Y127 -- 2017 YQ5, 2017 YO5, 2017 YN5, 2017 YM5, 2017 YK5, 2017 YJ5, 2017 YH5
W33Transit Dreams Obs., 1 in MPEC 2017-Y115 -- 3122
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2017-Y115 -- 2016 GF1
T14UH/Tholen NEO Follow-Up CFH Telescope in Hawaii, 1 in MPEC 2017-Y114 -- 2017 NS5
718Wiggins Obs. in Utah, 1 in MPEC 2017-Y124 -- 2017 YP5
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 27 December '17

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2342 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 is 100 years from today and for NEODyS is usually the year 2090. Both also post impact solutions beyond 100 years for a few 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
2017 YP5JPL Sentry23032070-209042.64398e-07-5.53-5.770JPL: Computed at 14:47 today Pacific time based on 30 observations spanning 1.6208 days (2017-Dec-25.51022 to 2017-Dec-27.13098). Diameter approximately 0.096 km. from weighted mean H=22.75.
2017 YO5JPL Sentry23032084-2108148.31726e-06-5.91-6.420JPL: Computed at 14:56 today Pacific time based on 22 observations spanning 1.9785 days (2017-Dec-25.45197 to 2017-Dec-27.43049). Diameter approximately 0.021 km. from weighted mean H=25.99.
2017 YE5JPL Sentry22062036-2116126.350446e-07-3.27-3.380JPL: Computed at 13:47 today Pacific time based on 21 observations spanning 6.3957 days (2017-Dec-21.00661 to 2017-Dec-27.40229). Diameter approximately 0.623 km. from weighted mean H=18.68.
2017 YS3NEODyS1610209311.3e-07-6.12-6.120NEODyS: "Based on 23 optical observations (of which 3 are rejected as outliers) from 2017-12-23.223 to 2017-12-25.223."
2017 YO3NEODyS16102052-2101452.52e-05-6.17-6.550NEODyS: "Based on 25 optical observations (of which 7 are rejected as outliers) from 2017-12-22.287 to 2017-12-25.173."
2017 SS12NEODyS16102071-2114211.28e-06-7.13-7.570NEODyS: "Based on 93 optical observations (of which 10 are rejected as outliers) from 2017-09-25.237 to 2017-10-02.158."
2014 HN197NEODyS16102019-2099511.62e-09-6.59-7.50NEODyS: "Based on 10 optical observations (of which 0 are rejected as outliers) from 2014-04-24.120 to 2014-04-25.132."

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 '17

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

2306Updated Traffic Report
2303Noted that JPL Sentry has posted 2017 YO5 as an impact risk - see above
Noted that JPL Sentry has posted 2017 YP5 as an impact risk - see above
2206Noted that JPL Sentry has posted 2017 YE5 as an impact risk - see above
2101Grabbed MPEC 2017-Y125 - 2017 YQ5 - see above
Grabbed MPEC 2017-Y126 - 2017 YK5 - see above
Grabbed MPEC 2017-Y127 - 2017 YO5 - see above
2038Grabbed MPEC 2017-Y116 - 2017 YE5 - see above
Grabbed MPEC 2017-Y117 - 2017 YF5 - see above
Grabbed MPEC 2017-Y118 - 2017 YG5 - see above
Grabbed MPEC 2017-Y119 - 2017 YH5 - see above
Grabbed MPEC 2017-Y120 - 2017 YJ5 - see above
Grabbed MPEC 2017-Y121 - 2017 YL5 - see above
Grabbed MPEC 2017-Y122 - 2017 YM5 - see above
Grabbed MPEC 2017-Y123 - 2017 YN5 - see above
Grabbed MPEC 2017-Y124 - 2017 YP5 - see above
1610Noted that NEODyS has updated its 2014 HN197 risk assessment - see above
Noted that NEODyS has updated its 2017 SS12 risk assessment - see above
Noted that NEODyS has posted 2017 YO3 as an impact risk - see above
Noted that NEODyS has posted 2017 YS3 as an impact risk - see above
Grabbed MPEC 2017-Y113 - 2002 LX - see above
Grabbed MPEC 2017-Y114 - 2017 NS5 - see above
Grabbed MPEC 2017-Y115 - Daily Orbit Update - see above