Contents  on 13 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 13 December '17

Six objects reported inside ten LD

Today there are six asteroidal objects reported within ten lunar distances (LD) of our home world. Closest is 2006 XY, which is inbound from 3.74 to 3.40 LD. Much further out, radar target 2017 VT14 enters the ten-LD sphere, zipping in from 10.28 to 8.16 LD.

Earth passage I D ~Size Distance today  Inside ten LD Notes
3.35 LD tomorrow 2006 XY 54 m  3.40 from 3.74 LD Dec. 5 - 23 NHATS target
3.43 LD Dec. 9 2017 WV12 26 m  8.13 to 10.33 LD Dec. 5 - 13 exits ten LD
3.83 LD Dec. 17 2017 VT14 84 m  8.16 from 10.28 LD today - Dec. 21 radar target, enters ten LD, comet nucleus?
3.96 LD Dec. 7 2017 XE 19 m  8.07 to 9.31 LD Dec. 1 - 14 NHATS target
6.15 LD Dec. 15 2017 XK1 31 m  7.15 from 8.88 LD yesterday - Dec. 18 DOU
9.71 LD tomorrow 2015 XX169 11 m  9.71 from 9.81 LD yesterday - Dec. 15 NHATS target
Approaching (sorted by 10-LD bubble entry date)
7.61 LD Dec. 24 2017 WZ14 31 m  14.20 from 15.16 LD Dec. 18 - 30 radar/NHATS target
3.7   LD Feb. 24* 2017 DR109 10 m  167.5 from 170.7 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
3.7   LD March 7* 2017 VR12 266 m  119.3 from 121.2 LD Feb. 28 - March 13 EPU +/- 20 mins.*, radar/NHATS target
* EPU = Earth passage uncertainty

This report was generated at 2034 UTC with today's DOU MPEC posting first follow-up for inbound 2017 XK1 and, from April 2014, for 2014 HJ197 (1.02 days added to 1.03-day discovery arc for this tiny object, which passed both Earth and Moon at less than 1.3 LD), along with follow-up for three departed objects: 2017 XS, 2017 UK1 (45.82 days added to 10.96-day observation arc), and 496817 1989 VB.

Reading:  Scientific American has an article lightly summing up publicly available science papers about 1I/`Oumuamua (A/2017 U1) (links).



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 13 December '17

The MPC's NEO Confirmation Page has 75 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 75 objects listed. Of these, 20 were "one nighters." So far The Tracking News has counted a total of 82 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 13 December '17

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 13 Dec. '17 >>  MPEC 2017-X102 - "13:05 UT" - Daily Orbit Update

Observers  on 13 December '17

A total of 23 observers appear in today's MPEC.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 25 in MPEC 2017-X102 -- 2017 XF, 2017 WX13, 2017 WG2, 2017 WF13, 2017 WE13, 2017 VW13, 2017 VS14, 2017 VK1, 2017 UZ4, 2017 SO17, 2014 JC31, 88188, 53319, 496817, 333888, 17182, 16657, 163696, 154988, 142040, 141670, 137062, 8037, 3200, 1865
T05ATLAS Haleakala in Hawaii, 18 in MPEC 2017-X102 -- 2015 GF1, 53430, 504680, 497096, 496817, 495858, 438897, 438430, 415029, 349928, 22753, 190208, 154555, 144898, 137805, 136839, 8037, 1980
T08ATLAS Mauna Loa in Hawaii, 6 in MPEC 2017-X102 -- 99907, 385580, 11405, 6050, 2329, 1036
073Bucharest Obs. in Romania, 1 in MPEC 2017-X102 -- 3200
309&Marco Micheli via Cerro Paranal in Chile, 2 in MPEC 2017-X102 -- 2017 UR51, 2017 UK1
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 4 in MPEC 2017-X102 -- 2017 XD, 2017 WS1, 2017 QO17, 2017 PX24
A77Chante-Perdrix Obs. in France, 1 in MPEC 2017-X102 -- 3200
W845Lori Allen via DECam in Chile, 1 in MPEC 2017-X102 -- 2014 HJ197
L05Dridri Obs. in Italy, 1 in MPEC 2017-X102 -- 3200
006Fabra Obs. in Spain, 2 in MPEC 2017-X102 -- 140158, 3200
V37LCO Fort Davis in Texas, 1 in MPEC 2017-X102 -- 2017 XL1
Z22MASTER IAC Obs. in the Canary Islands, 1 in MPEC 2017-X102 -- 497176
G96Mt. Lemmon Survey (MLS) in Arizona, 2 in MPEC 2017-X102 -- 2014 TT57, 2014 TO35
G34Oberfrauendorf Obs. in Germany, 1 in MPEC 2017-X102 -- 3200
F51Pan-STARRS 1 (PS1) in Hawaii, 17 in MPEC 2017-X102 -- 2017 VX13, 2017 UB5, 2017 OH68, 2014 YC15, 2014 QY432, 2014 QW296, 2014 JN57, 2013 PX6, 2008 AX28, 85182, 68278, 53319, 445775, 439898, 153814, 11398, 8566
B49Paus Obs. in Spain, 1 in MPEC 2017-X102 -- 3200
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 6 in MPEC 2017-X102 -- 2017 XS, 2017 WX12, 2014 YC15, 2014 JC31, 2013 US3, 2009 BL71
V83Rolling Hills Obs. in Missouri, 1 in MPEC 2017-X102 -- 3200
L23Schela Obs. in Romania, 4 in MPEC 2017-X102 -- 2017 XS, 2017 WX12, 1999 AF4, 3200
691Spacewatch 0.9m telescope in Arizona, 10 in MPEC 2017-X102 -- 2017 XD, 2017 XC1, 2017 WP12, 2017 WP1, 2017 WL16, 2017 VV14, 2017 UW4, 2017 UH44, 2017 NU6, 2016 YW7
291Spacewatch 1.8m telescope in Arizona, 11 in MPEC 2017-X102 -- 2017 WV14, 2017 WT1, 2017 WS, 2017 WO1, 2017 WN28, 2017 VE15, 2017 RL1, 2015 DP, 2015 CV13, 2010 EX119, 2010 CM
I52Steward Obs. Mt. Lemmon Station in Arizona, 20 in MPEC 2017-X102 -- 2017 XR, 2017 XM1, 2017 XK1, 2017 XF, 2017 XD1, 2017 XC1, 2017 XB1, 2017 WS12, 2017 WK14, 2017 WJ28, 2017 WH15, 2017 WF13, 2017 WE2, 2017 WD16, 2017 WA15, 2017 WA13, 2017 UY5, 2017 UF52, 2017 NH, 2015 AC45
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2017-X102 -- 2016 FA
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 13 December '17

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 UR51NEODyS1611R E M O V E D-
2017 UK1NEODyS1611R E M O V E D-
2005 TM173JPL Sentry20212017-21161559.507796e-07-5.26-5.980JPL: Computed at 08:06 April 8th Pacific time based on 6 observations spanning 1.9467 days (2005-Oct-09.20072 to 2005-Oct-11.14743). Diameter approximately 0.051 km. from weighted mean H=24.12.

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 13 December '17

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

2034Generated Traffic Report
2021Noted that JPL Sentry has updated its 2005 TM173 risk assessment - see above
1611Noted that NEODyS has removed 2017 UK1 as an impact risk - see above
Noted that NEODyS has removed 2017 UR51 as an impact risk - see above
Grabbed MPEC 2017-X102 - Daily Orbit Update - see above