Contents  on 25 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 25 December '17

Ten objects reported inside ten LD

There are ten minor planets known to be within ten lunar distances (LD) of Earth today. Nearest of these, within our planet's sphere of gravitational influence (SOI), is 2017 YS1, which moves away from 1.95 to 2.16 LD.

Earth passage I D ~Size Distance today  Inside ten LD Notes
1.77 LD Dec. 15 2017 YD1 3 m  6.14 to 6.77 LD Nov. 30 - Dec. 31 NHATS target, risk
1.93 LD yesterday 2017 YS1 6 m  1.95 to 2.16 LD Dec. 11 - Jan. 7 NHATS target, Moon closest 1.54 LD at 0947 UTC - DOU
2.08 LD Dec. 20 2017 YO3 8 m  8.36 to 10.15 LD Dec. 15 - 25 NEW, exits ten LD - MPEC
2.24 LD Dec. 27 2017 YD2 6 m  3.05 from 4.53 LD Dec. 21 - Jan. 1 NHATS target, risk
2.88 LD Dec. 22 2017 YE 7 m  3.99 to 4.78 LD Dec. 13 - 31 NHATS target - DOU
4.8   LD Dec. 19* 2017 YW3 18 m  5.9 to 6.4 LD Dec. 5 - Jan. 1 NEW, EPU +/- 26 mins.* - MPEC
5.13 LD tomorrow 2017 YQ1 41 m  5.77 from 9.00 LD yesterday - Dec. 28 DOU
7.62 LD yesterday 2017 WZ14 32 m  7.62 to 7.71 LD Dec. 18 - 30 radar/NHATS target
7.90 LD Dec. 22 2017 YW 15 m  8.91 to 9.90 LD Dec. 19 - 26
8.47 LD today 2017 YR3 29 m  8.47 LD Dec. 21 - 29 NEW, Earth closest at 1340 UTC - MPEC
Approaching (sorted by 10-LD bubble entry date)
7.74 LD Dec. 30 2017 YU1 19 m  10.68 from 11.93 LD tomorrow - Jan. 3 NHATS target - DOU
3.7   LD Feb. 24* 2017 DR109 10 m  130.4 from 133.4 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
3.8   LD March 7* 2017 VR12 270 m  98.0 from 99.7 LD Feb. 28 - March 13 EPU +/- 5 mins.*, radar/NHATS target - DOU
* EPU = Earth passage uncertainty

This report was generated at 2214 UTC with the discoveries of 2017 YW3, 2017 YR3, and 2017 YO3 -- all in the above active traffic table. Today's DOU MPEC has the recovery of distant 2009 BE58, first follow-up for inbound 2017 YQ1, additional observation of approaching 2017 YU1, outbound 2017 YS1, and departed 2017 YT1, and continuing follow-up for approaching 2017 VR12, outbound 2017 YE, departed objects 2017 WJ16, 2017 VT14, 2006 XY, and 496817 1989 VB, and distant 208023 1999 AQ10, plus astrometry from September for 2017 RO17.



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 objects that have come within ten LD since A/CC began these traffic reports (2007) but are not now 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 25 December '17

The MPC's NEO Confirmation Page has 106 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 106 objects listed. Of these, 59 were "one nighters." So far The Tracking News has counted a total of 135 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 25 December '17

Minor Planet Electronic Circulars

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


MPEC 2017-Y98 - "22:24 UT" - 2015 YD18


MPEC 2017-Y97 - "22:21 UT" - 2014 SP142


MPEC 2017-Y96 - "22:19 UT" - 2013 OW2


MPEC 2017-Y95 - "19:42 UT" - 2017 YW3


MPEC 2017-Y94 - "19:38 UT" - 2017 YS3


MPEC 2017-Y93 - "19:35 UT" - 2017 YQ3


MPEC 2017-Y92 - "19:31 UT" - 2017 YX3


MPEC 2017-Y91 - "19:28 UT" - 2017 YV3


MPEC 2017-Y90 - "19:24 UT" - 2017 YU3


MPEC 2017-Y89 - "19:20 UT" - 2017 YT3


MPEC 2017-Y88 - "19:15 UT" - 2017 YR3


MPEC 2017-Y87 - "19:11 UT" - 2017 YP3


MPEC 2017-Y86 - "19:07 UT" - 2017 YO3


MPEC 2017-Y85 - "19:02 UT" - 2017 YN3


<< DOU on 25 Dec. '17 >>  MPEC 2017-Y84 - "13:04 UT" - Daily Orbit Update

Observers  on 25 December '17

A total of 25 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 9 in MPEC 2017-Y84 -- 2017 RO17, 2017 RM15, 2017 RK15, 2017 QV35, 2017 QH33, 2017 OJ68, 2012 VF82, 2003 SJ154, 475967
T05ATLAS Haleakala in Hawaii, 20 in MPECs 2017-Y84 & 2017-Y95 -- 2017 YW3, 2007 XP3, 504928, 504887, 497176, 496817, 457768, 374851, 349928, 21374, 17182, 154991, 154988, 154589, 153349, 136849, 9950, 8567, 8037, 2368
T08ATLAS Mauna Loa in Hawaii, 2 in MPEC 2017-Y84 -- 2017 VT14, 2006 XY
I47Auger Obs. in Argentina, 2 in MPECs 2017-Y84 & 2017-Y85 -- 2017 YN3, 2017 TS3
160Castelmartini Obs. in Italy, 3 in MPEC 2017-Y84 -- 2017 QL33, 21088, 11066
703Catalina Sky Survey (CSS) in Arizona, 17 in MPECs 2017-Y84 & 2017-Y95 -- 2017 YW3, 2017 VR12, 2015 YR1, 504025, 475967, 36284, 337228, 302311, 281365, 208023, 194126, 177651, 137924, 137078, 111253, 6053, 1864
V06Catalina Sky Survey Kuiper Telescope (CSS-Kuiper) in Arizona, 5 in MPECs 2017-Y84, 2017-Y86, 2017-Y87, 2017-Y88 & 2017-Y93 -- 2017 YR3, 2017 YQ3, 2017 YP3, 2017 YO3, 2017 YE
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 7 in MPECs 2017-Y84, 2017-Y85, 2017-Y86, 2017-Y87, 2017-Y88, 2017-Y93 & 2017-Y94 -- 2017 YS3, 2017 YR3, 2017 YQ3, 2017 YP3, 2017 YO3, 2017 YN3, 2017 YH
511Haute Provence Obs. in Germany, 1 in MPEC 2017-Y84 -- 2017 XJ62
568_Marco Micheli on Mauna Kea in Hawaii, 3 in MPECs 2017-Y89, 2017-Y91 & 2017-Y93 -- 2017 YV3, 2017 YT3, 2017 YQ3
711McDonald Obs. in Texas, 6 in MPECs 2017-Y86, 2017-Y90, 2017-Y92, 2017-Y93, 2017-Y94 & 2017-Y95 -- 2017 YX3, 2017 YW3, 2017 YU3, 2017 YS3, 2017 YQ3, 2017 YO3
B67Mirasteilas Obs. in Switzerland, 2 in MPEC 2017-Y84 -- 2017 XV2, 2014 QW296
G96Mt. Lemmon Survey (MLS) in Arizona, 26 in MPECs 2017-Y84, 2017-Y86, 2017-Y87, 2017-Y88 & 2017-Y94 -- 2017 YS3, 2017 YR3, 2017 YP3, 2017 YO3, 2017 XL62, 2017 SE19, 2015 BN509, 2015 BF4, 2007 XP3, 505667, 497176, 495891, 483560, 418416, 267221, 248926, 242708, 210012, 162273, 162038, 140039, 136849, 9950, 8567, 5836, 3988
F51Pan-STARRS 1 (PS1) in Hawaii, 29 in MPECs 2017-Y84, 2017-Y89, 2017-Y90, 2017-Y91, 2017-Y92, 2017-Y93 & 2017-Y96 -- 2017 YX3, 2017 YV3, 2017 YU3, 2017 YT3, 2017 YQ3, 2017 VK1, 2017 UZ4, 2015 VO66, 2013 OW2, 2009 BE58, 2008 CC175, 2006 XY, 489486, 480856, 474574, 444628, 439908, 439898, 418416, 348306, 186823, 177255, 163732, 152558, 140039, 138175, 137084, 8566, 5836
D29Purple Mtn. Obs. Xuyi Station in China, 1 in MPEC 2017-Y84 -- 323300
619Sabadell Obs. in Spain, 1 in MPEC 2017-Y84 -- 418849
H36Sandlot Obs. in Kansas, 1 in MPEC 2017-Y95 -- 2017 YW3
204Schiaparelli Obs. in Italy, 2 in MPECs 2017-Y89 & 2017-Y91 -- 2017 YV3, 2017 YT3
691Spacewatch 0.9m telescope in Arizona, 3 in MPEC 2017-Y84 -- 2017 RH15, 499490, 234145
291Spacewatch 1.8m telescope in Arizona, 4 in MPECs 2017-Y84, 2017-Y89, 2017-Y93 & 2017-Y96 -- 2017 YT3, 2017 YQ3, 2017 WJ16, 2013 OW2
V78Spirit Marsh Obs. in Minnesota, 1 in MPEC 2017-Y84 -- 3122
I52Steward Obs. Mt. Lemmon Station in Arizona, 8 in MPECs 2017-Y86, 2017-Y87, 2017-Y88, 2017-Y89, 2017-Y91, 2017-Y92, 2017-Y94 & 2017-Y95 -- 2017 YX3, 2017 YW3, 2017 YV3, 2017 YT3, 2017 YS3, 2017 YR3, 2017 YP3, 2017 YO3
926Tenagra II Obs. in Arizona, 14 in MPECs 2017-Y84, 2017-Y86, 2017-Y88, 2017-Y89, 2017-Y90, 2017-Y91, 2017-Y92, 2017-Y94, 2017-Y95 & 2017-Y98 -- 2017 YX3, 2017 YW3, 2017 YV3, 2017 YU3, 2017 YU1, 2017 YT3, 2017 YT1, 2017 YS3, 2017 YS1, 2017 YR3, 2017 YR1, 2017 YQ1, 2017 YO3, 2015 YD18
T14UH/Tholen NEO Follow-Up CFH Telescope in Hawaii, 2 in MPECs 2017-Y84 & 2017-Y97 -- 2017 WC15, 2014 SP142
C51WISE in Earth polar orbit, 1 in MPEC 2017-Y85 -- 2017 YN3
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 25 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 YS3JPL Sentry22002044-209332.247e-08-6.72-6.790JPL: Computed at 13:46 today Pacific time based on 23 observations spanning 1.9996 days (2017-Dec-23.22262 to 2017-Dec-25.22224). Diameter approximately 0.080 km. from weighted mean H=23.14.
2017 YO3JPL Sentry22512049-2067264.120445e-05-5.85-5.920JPL: Computed at 13:22 today Pacific time based on 25 observations spanning 2.8852 days (2017-Dec-22.28665 to 2017-Dec-25.17181). Diameter approximately 0.008 km. from weighted mean H=28.20.

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 25 December '17

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

2251Noted that JPL Sentry has posted 2017 YO3 as an impact risk - see above
Grabbed MPEC 2017-Y96 - 2013 OW2 - see above
Grabbed MPEC 2017-Y97 - 2014 SP142 - see above
Grabbed MPEC 2017-Y98 - 2015 YD18 - see above
2214Generated Traffic Report
2200Noted that JPL Sentry has posted 2017 YS3 as an impact risk - see above
2032Grabbed MPEC 2017-Y93 - 2017 YQ3 - see above
Grabbed MPEC 2017-Y94 - 2017 YS3 - see above
Grabbed MPEC 2017-Y95 - 2017 YW3 - see above
1936Grabbed MPEC 2017-Y90 - 2017 YU3 - see above
Grabbed MPEC 2017-Y91 - 2017 YV3 - see above
Grabbed MPEC 2017-Y92 - 2017 YX3 - see above
1922Grabbed MPEC 2017-Y87 - 2017 YP3 - see above
Grabbed MPEC 2017-Y88 - 2017 YR3 - see above
Grabbed MPEC 2017-Y89 - 2017 YT3 - see above
1912Grabbed MPEC 2017-Y85 - 2017 YN3 - see above
Grabbed MPEC 2017-Y86 - 2017 YO3 - see above
1600Grabbed MPEC 2017-Y84 - Daily Orbit Update - see above