Contents  on 5 January '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 January '18

Two objects reported inside ten LD

Today there are two asteroids known to be inside ten lunar distances (LD) of Earth. Nearest is 2017 YD7, headed out from 6.64 to 8.47 LD.

Earth passage I D ~Size Distance today  Inside ten LD Notes
1.93 LD Dec. 24 2017 YS1 6 m  8.46 to 9.16 LD Dec. 11 - Jan. 7 NHATS target
4.73 LD Jan. 3 2017 YD7 12 m  6.64 to 8.47 LD Dec. 30 - tomorrow NHATS target
Approaching (sorted by 10-LD bubble entry date)
3.7   LD Feb. 24* 2017 DR109 10 m  101.8 from 99.1 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
3.76 LD March 7 2017 VR12 272 m  81.38 from 82.81 LD Feb. 28 - March 13 radar/NHATS target
* EPU = Earth passage uncertainty

This report was generated at 1812 UTC with first follow-up in today's DOU MPEC for departed objects 2017 YW3 (10.22 days added to discovery and some additional observations running 1.75 days) and risk-listed 2017 YM1 (14.31 days tacked onto 1.72-day discovery arc), plus continuing follow-up for departed 2017 YH1.

Reading:  Phys.org has an article today by postdoc Fabo Feng bringing attention to his co-authored November science paper proposing that 1I/`Oumuamua (A/2017 U1) (see A/CC's expanded links page) emanates from the Local Association of stars. This same article appeared yesterday under a different title at The Conversation.



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 5 January '18

The MPC's NEO Confirmation Page has 48 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 48 objects listed. Of these, nineteen were "one nighters." So far The Tracking News has counted a total of 52 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 January '18

Minor Planet Electronic Circulars

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


<< DOU on 5 Jan. '18 >>  MPEC 2018-A15 - "13:04 UT" - Daily Orbit Update


MPEC 2018-A14 - "00:28 UT" - 2017 YK8

Observers  on 5 January '18

Sixteen observers appear in today's MPECs.

CodeObserver / observatory
T05ATLAS Haleakala in Hawaii, 7 in MPEC 2018-A15 -- 496818, 361071, 333888, 189173, 6050, 1980, 1627
T08ATLAS Mauna Loa in Hawaii, 14 in MPEC 2018-A15 -- 2017 YD8, 2017 QL33, 1999 AF4, 96590, 475967, 348314, 302311, 17511, 163696, 137062, 12711, 6053, 3122, 1864
Z36Cancelada Obs., 1 in MPEC 2018-A15 -- 3122
160Castelmartini Obs. in Italy, 7 in MPEC 2018-A15 -- 2017 YP4, 2007 AG, 348314, 17182, 16657, 137805, 1980
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 4 in MPECs 2018-A14 & 2018-A15 -- 2017 YZ1, 2017 YK8, 2017 WS1, 2017 UE45
695^Spacewatch via Kitt Peak Natl. Obs. (KPNO) in Arizona, 5 in MPEC 2018-A15 -- 2017 YM1, 2017 YE8, 2017 WN28, 2017 WK14, 2017 SN2
568_Marco Micheli on Mauna Kea in Hawaii, 1 in MPEC 2018-A14 -- 2017 YK8
G96Mt. Lemmon Survey in Arizona, 1 in MPEC 2018-A15 -- 2017 YH1
Z80Northolt Branch Obs. in England, 2 in MPEC 2018-A15 -- 1999 AF4, 6053
F51Pan-STARRS 1 (PS1) in Hawaii, 15 in MPECs 2018-A14 & 2018-A15 -- 2017 YO4, 2017 YK8, 2017 WK14, 2017 UR7, 2015 BF4, 2013 XS3, 2013 MZ5, 2008 AX28, 504887, 499307, 494975, 407653, 22753, 16834, 154991
A53Peschiera del Garda Obs. in Italy, 1 in MPEC 2018-A15 -- 2017 QL33
691Spacewatch 0.9m telescope in Arizona, 17 in MPEC 2018-A15 -- 2017 YW3, 2017 YA6, 2017 XV2, 2017 XT61, 2017 XG2, 2017 XB1, 2017 WW12, 2017 WG2, 2017 VX1, 2017 TS3, 2017 SS19, 2017 RH15, 2017 NU6, 2014 WG365, 2009 QL8, 2004 BB, 2003 YX1
291Spacewatch 1.8m telescope in Arizona, 9 in MPECs 2018-A14 & 2018-A15 -- 2017 YW3, 2017 YL6, 2017 YK8, 2017 XN61, 2017 XL2, 2017 WN16, 2017 VW13, 2017 RL, 2017 OP19
V78Spirit Marsh Obs. in Minnesota, 1 in MPEC 2018-A15 -- 3122
I52Steward Obs. Mt. Lemmon Station in Arizona, 11 in MPEC 2018-A15 -- 2017 YH1, 2017 YG1, 2017 YF5, 2017 XU2, 2017 XN61, 2017 XL2, 2017 XG2, 2017 XD62, 2017 WK28, 2017 WE2, 2017 VW13
926Tenagra II Obs. in Arizona, 6 in MPECs 2018-A14 & 2018-A15 -- 2017 YX4, 2017 YU3, 2017 YO6, 2017 YK8, 2017 YE5, 2017 XU2
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 5 January '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 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 YE8NEODyS20352093-211341.34e-08-8.27-8.530NEODyS: "Based on 22 optical observations (of which 4 are rejected as outliers) from 2017-12-29.286 to 2018-01-05.355."
JPL Sentry16562112-211756.9385e-07-6.64-7.090JPL: Computed at 08:50 today Pacific time based on 22 observations spanning 7.0684 days (2017-Dec-29.28539 to 2018-Jan-05.35375). Diameter approximately 0.026 km. from weighted mean H=25.55.
2017 YO6NEODyS20352085-211772.39e-06-4.46-4.50NEODyS: "Based on 17 optical observations (of which 1 are rejected as outliers) from 2017-12-26.478 to 2018-01-05.280."
JPL Sentry16562059-211683.6621674e-06-4.29-4.400JPL: Computed at 08:48 today Pacific time based on 17 observations spanning 9.8023 days (2017-Dec-26.47691 to 2018-Jan-05.27917). Diameter approximately 0.120 km. from weighted mean H=22.34.
2017 YL6NEODyS2035R E M O V E D-
JPL Sentry1656R E M O V E DJPL: Risk listing removed at 1602 UTC today
2017 YE5NEODyS2035R E M O V E D-
JPL Sentry16562078-207814.442e-10-6.36-6.360JPL: Computed at 08:35 today Pacific time based on 30 observations spanning 15.269 days (2017-Dec-21.00661 to 2018-Jan-05.27592). Diameter approximately 0.580 km. from weighted mean H=18.82.
2017 YZ1NEODyS20352047-206742.11e-04-1.27-1.271NEODyS: "Based on 43 optical observations (of which 4 are rejected as outliers) from 2017-12-20.426 to 2018-01-04.253."
JPL Sentry20022047-211694.9115537e-05-1.91-1.911JPL: Computed at 08:47 today Pacific time based on 43 observations spanning 14.827 days (2017-Dec-20.42481 to 2018-Jan-04.25204). Diameter approximately 0.260 km. from weighted mean H=20.60.
2017 YM1NEODyS20352035-2110332.23e-04-4.04-4.190NEODyS: "Based on 20 optical observations (of which 2 are rejected as outliers) from 2017-12-20.410 to 2018-01-05.442."
JPL Sentry16562048-2103183.0833579e-05-4.89-5.140JPL: Computed at 07:59 today Pacific time based on 20 observations spanning 16.033 days (2017-Dec-20.40891 to 2018-Jan-05.44143). Diameter approximately 0.028 km. from weighted mean H=25.41.
2017 VW13NEODyS2035R E M O V E D-
JPL Sentry16562097-209717.953e-08-5.24-5.240JPL: Computed at 07:55 today Pacific time based on 210 observations spanning 52.844 days (2017-Nov-13.64011 to 2018-Jan-05.48427). Diameter approximately 0.250 km. from weighted mean H=20.65.
2008 EL68JPL Sentry16562018-21136133.32769959e-05-5.25-6.010JPL: 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 5 January '18

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

2035Noted that NEODyS has removed 2017 VW13 as an impact risk - see above
Noted that NEODyS has removed 2017 YE5 as an impact risk - see above
Noted that NEODyS has updated its 2017 YE8 risk assessment - see above
Noted that NEODyS has removed 2017 YL6 as an impact risk - see above
Noted that NEODyS has updated its 2017 YM1 risk assessment - see above
Noted that NEODyS has updated its 2017 YO6 risk assessment - see above
Noted that NEODyS has updated its 2017 YZ1 risk assessment - see above
2002Noted that JPL Sentry has updated its 2017 YZ1 risk assessment - see above
1812Generated Traffic Report
1656Noted that JPL Sentry has updated its 2008 EL68 risk assessment - see above
Noted that JPL Sentry has updated its 2017 VW13 risk assessment - see above
Noted that JPL Sentry has updated its 2017 YE5 risk assessment - see above
Noted that JPL Sentry has updated its 2017 YE8 risk assessment - see above
Noted that JPL Sentry has removed 2017 YL6 as an impact risk - see above
Noted that JPL Sentry has updated its 2017 YM1 risk assessment - see above
Noted that JPL Sentry has updated its 2017 YO6 risk assessment - see above
Grabbed MPEC 2018-A15 - Daily Orbit Update - see above
0045Grabbed MPEC 2018-A14 - 2017 YK8 - see above