Contents  on 26 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 26 December '17

Eleven objects reported inside ten LD

Eleven asteroidal objects are known to be less tan ten lunar distances (LD) from Earth today. 2017 YS1 is the nearest and exits Earth's sphere of gravitational influence (SOI) on its way from 2.16 to 2.58 LD, while risk-listed 2017 YD2 enters the SOI, slipping in from 3.05 to 2.25 LD.

Earth passage I D ~Size Distance today  Inside ten LD Notes
0.6   LD Dec. 28* 2017 YZ4 9 m  3.6 from 5.7 LD Dec. 23 - Jan. 2 NEW, EPU +/- 6 mins.*, intruder - MPEC
1.77 LD Dec. 15 2017 YD1 3 m  6.77 to 7.41 LD Nov. 30 - Dec. 31 NHATS target, risk
1.93 LD Dec. 24 2017 YS1 6 m  2.16 to 2.58 LD Dec. 11 - Jan. 7 NHATS target, exits Earth SOI
2.24 LD tomorrow 2017 YD2 6 m  2.25 from 3.05 LD Dec. 21 - Jan. 1 NHATS target, enters Earth SOI, risk
2.88 LD Dec. 22 2017 YE 7 m  4.78 to 5.64 LD Dec. 13 - 31 NHATS target
4.84 LD Dec. 19 2017 YW3 17 m  6.32 to 6.77 LD Dec. 5 - Jan. 1 DOU
5.13 LD today 2017 YQ1 41 m  5.13 LD Dec. 24 - 28 Earth closest at 1324 UTC
7.62 LD Dec. 24 2017 WZ14 32 m  7.71 to 7.96 LD Dec. 18 - 30 radar/NHATS target
7.74 LD Dec. 30 2017 YU1 19 m  9.58 from 10.68 LD today - Jan. 3 NHATS target, enters ten LD
7.90 LD Dec. 22 2017 YW 15 m  9.90 to 11.13 LD Dec. 19 - 26 exits ten LD
8.47 LD yesterday 2017 YR3 29 m  8.50 to 8.73 LD Dec. 21 - 29
Approaching (sorted by 10-LD bubble entry date)
3.7   LD Feb. 24* 2017 DR109 10 m  127.4 from 130.4 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
3.8   LD March 7* 2017 VR12 272 m  96.4 from 98.0 LD Feb. 28 - March 13 EPU +/- 5 mins.*, radar/NHATS target - DOU
* EPU = Earth passage uncertainty

This report was updated at 2207 UTC with the discovery of inbound intruder 2017 YZ4 (MPEC). Your first local flying rocks traffic report was generated at 1950 UTC with the recovery of distant 450894 2008 BT18 in today's DOU MPEC along with additional observation of outbound 2017 YW3 and first follow-up for departed 2017 YT1, plus continuing follow-up for approaching 2017 VR12 and departed objects 2017 YH1, 2017 VT14, and 2006 XY. The DOU also has astrometry from September for risk-listed instruders 2017 SS12 (which flew inside the Moon's SOI) and 2017 SU17, and from October 2010 for 503941 2003 UV11.



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 26 December '17

The MPC's NEO Confirmation Page has 110 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 110 objects listed. Of these, 62 were "one nighters." So far The Tracking News has counted a total of 147 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 26 December '17

Minor Planet Electronic Circulars

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


MPEC 2017-Y112 - "19:52 UT" - 2017 YZ4


MPEC 2017-Y111 - "19:48 UT" - 2017 YY4


MPEC 2017-Y110 - "19:45 UT" - 2009 EV = 2008 PG1 = 2017 YQ4


MPEC 2017-Y109 - "19:41 UT" - 2017 YX4


MPEC 2017-Y108 - "19:37 UT" - 2017 YW4


MPEC 2017-Y107 - "19:33 UT" - 2017 YV4


MPEC 2017-Y106 - "19:30 UT" - 2017 YU4


MPEC 2017-Y105 - "19:26 UT" - 2017 YT4


MPEC 2017-Y104 - "19:22 UT" - 2017 YS4


MPEC 2017-Y103 - "19:19 UT" - 2017 YR4


MPEC 2017-Y102 - "19:15 UT" - 2017 YQ4


MPEC 2017-Y101 - "19:12 UT" - 2017 YP4


MPEC 2017-Y100 - "19:03 UT" - 2017 YO4


<< DOU on 26 Dec. '17 >>  MPEC 2017-Y99 - "13:05 UT" - Daily Orbit Update

Observers  on 26 December '17

A total of 42 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 13 in MPEC 2017-Y99 -- 2017 XK2, 2017 SZ20, 2017 SW14, 2017 SU17, 2017 SS12, 2017 SP19, 2017 SP14, 2017 SG16, 2017 SG10, 2017 RY17, 2017 QP33, 2012 JU4, 506859
T05ATLAS Haleakala in Hawaii, 19 in MPECs 2017-Y99, 2017-Y101 & 2017-Y109 -- 2017 YX4, 2017 YP4, 2017 XJ62, 2017 QL33, 2007 AT2, 505093, 475967, 418849, 417217, 374851, 17511, 163696, 154555, 137078, 10165, 6053, 3122, 1864, 1580
T08ATLAS Mauna Loa in Hawaii, 4 in MPECs 2017-Y99 & 2017-Y101 -- 2017 YP4, 2017 QJ18, 2007 XP3, 333888
I47Auger Obs. in Argentina, 1 in MPEC 2017-Y101 -- 2017 YP4
C77Bernezzo Obs. in Italy, 1 in MPEC 2017-Y101 -- 2017 YP4
073Bucharest Obs. in Romania, 1 in MPEC 2017-Y99 -- 418849
160Castelmartini Obs. in Italy, 12 in MPEC 2017-Y99 -- 2017 VU14, 53110, 504928, 504887, 438430, 418849, 361071, 189173, 154988, 137805, 136849, 2368
703Catalina Sky Survey (CSS) in Arizona, 30 in MPEC 2017-Y99 -- 2017 XT61, 2017 XG2, 2014 YC15, 96590, 68278, 507366, 506859, 504887, 500749, 496861, 457768, 439908, 438430, 349928, 322763, 21374, 190208, 185853, 17182, 164221, 144898, 143992, 143651, 138175, 137805, 137052, 136839, 101873, 8037, 1981
V06Catalina Sky Survey Kuiper Telescope (CSS-Kuiper) in Arizona, 6 in MPECs 2017-Y101, 2017-Y102, 2017-Y103, 2017-Y106, 2017-Y107 & 2017-Y108 -- 2017 YW4, 2017 YV4, 2017 YU4, 2017 YR4, 2017 YQ4, 2017 YP4
K51Celado Obs. in Italy, 1 in MPEC 2017-Y101 -- 2017 YP4
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. in Chile, 1 in MPEC 2017-Y99 -- 2017 XM1
106Crni Vrh Obs. in Slovenia, 1 in MPEC 2017-Y107 -- 2017 YV4
113Drebach Obs. in Germany, 4 in MPECs 2017-Y99, 2017-Y101, 2017-Y103 & 2017-Y109 -- 2017 YX4, 2017 YW3, 2017 YR4, 2017 YP4
I48El Catalejo Obs. in Argentina, 1 in MPEC 2017-Y101 -- 2017 YP4
595Farra d'Isonzo Obs. in Italy, 2 in MPECs 2017-Y101 & 2017-Y103 -- 2017 YR4, 2017 YP4
203GiaGa Obs. in Italy, 2 in MPECs 2017-Y101 & 2017-Y103 -- 2017 YR4, 2017 YP4
K88GINOP-KHK in Hungary, 3 in MPECs 2017-Y101, 2017-Y109 & 2017-Y112 -- 2017 YZ4, 2017 YX4, 2017 YP4
G48Harlingten Research Obs. in New Mexico, 1 in MPEC 2017-Y101 -- 2017 YP4
H15ISON New Mexico Obs. in New Mexico, 2 in MPEC 2017-Y99 -- 2017 SO17, 385580
U69[program code "[" (25) via iTelescope Obs. Auberry in northern California, 1 in MPEC 2017-Y99 -- 1980
U69\program code "\" (26) via iTelescope Obs. Auberry in northern California, 1 in MPEC 2017-Y99 -- 162269
Q62[M. Suzuki in Japan via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2017-Y101 -- 2017 YP4
P93JAXA Space Tracking & Communications Center (JAXA STCC) in Japan, 2 in MPEC 2017-Y99 -- 2017 YH1, 302311
246KLENOT in the Czech Republic, 3 in MPECs 2017-Y101, 2017-Y103 & 2017-Y109 -- 2017 YX4, 2017 YR4, 2017 YP4
568_Marco Micheli on Mauna Kea in Hawaii, 3 in MPECs 2017-Y100, 2017-Y105 & 2017-Y111 -- 2017 YY4, 2017 YT4, 2017 YO4
711McDonald Obs. in Texas, 5 in MPECs 2017-Y101, 2017-Y103, 2017-Y107, 2017-Y108 & 2017-Y109 -- 2017 YX4, 2017 YW4, 2017 YV4, 2017 YR4, 2017 YP4
B67Mirasteilas Obs. in Switzerland, 5 in MPEC 2017-Y99 -- 2017 XT61, 2017 VR12, 2017 QL33, 2016 AU8, 2007 AT2
X31MPC code X31, 1 in MPEC 2017-Y101 -- 2017 YP4
G96Mt. Lemmon Survey (MLS) in Arizona, 34 in MPECs 2017-Y99, 2017-Y102, 2017-Y103, 2017-Y106, 2017-Y107, 2017-Y108 & 2017-Y112 -- 2017 YZ4, 2017 YW4, 2017 YV4, 2017 YU4, 2017 YU3, 2017 YR4, 2017 YQ4, 2017 YE1, 2017 XR61, 2017 XQ61, 2017 XL60, 2017 VK2, 2017 UW42, 2017 PS30, 2015 DC200, 88264, 52760, 504392, 503293, 450894, 381906, 38091, 331510, 329669, 323300, 265187, 259221, 20236, 194268, 189173, 174881, 154991, 152680, 144898
C47Nonndorf Obs. in Austria, 1 in MPEC 2017-Y99 -- 2017 YH1
F51Pan-STARRS 1 (PS1) in Hawaii, 27 in MPECs 2017-Y99, 2017-Y100, 2017-Y102, 2017-Y104, 2017-Y105 & 2017-Y111 -- 2017 YY4, 2017 YT4, 2017 YT1, 2017 YS4, 2017 YQ4, 2017 YO4, 2017 YB2, 2017 XV2, 2017 VK1, 2017 UF52, 2017 TO4, 2017 SL2, 2015 KJ57, 2012 LE11, 2006 XY, 507366, 500094, 480856, 439898, 399611, 374851, 267337, 238063, 168378, 152558, 10150, 8566
B49Paus Obs. in Spain, 1 in MPEC 2017-Y101 -- 2017 YP4
H36Sandlot Obs. in Kansas, 2 in MPECs 2017-Y103 & 2017-Y109 -- 2017 YX4, 2017 YR4
204Schiaparelli Obs. in Italy, 1 in MPEC 2017-Y101 -- 2017 YP4
G40(program code "(" (17) via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2017-Y101 -- 2017 YP4
G409B. Lutkenhoner in Germany via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2017-Y101 -- 2017 YP4
691Spacewatch 0.9m telescope in Arizona, 8 in MPEC 2017-Y99 -- 2017 YQ3, 2017 XL2, 2017 WY12, 2017 VT14, 2017 UZ4, 2017 OP19, 2014 WG365, 216985
291Spacewatch 1.8m telescope in Arizona, 3 in MPECs 2017-Y100, 2017-Y104 & 2017-Y105 -- 2017 YT4, 2017 YS4, 2017 YO4
V78Spirit Marsh Obs. in Minnesota, 1 in MPEC 2017-Y99 -- 3122
I52Steward Obs. Mt. Lemmon Station in Arizona, 11 in MPECs 2017-Y99, 2017-Y100, 2017-Y101, 2017-Y102, 2017-Y103, 2017-Y106, 2017-Y107, 2017-Y108, 2017-Y109, 2017-Y111 & 2017-Y112 -- 2017 YZ4, 2017 YY4, 2017 YX4, 2017 YW4, 2017 YV4, 2017 YU4, 2017 YR4, 2017 YQ4, 2017 YP4, 2017 YO4, 2017 XU2
926Tenagra II Obs. in Arizona, 10 in MPECs 2017-Y100, 2017-Y101, 2017-Y102, 2017-Y103, 2017-Y105, 2017-Y107, 2017-Y108, 2017-Y109, 2017-Y111 & 2017-Y112 -- 2017 YZ4, 2017 YY4, 2017 YX4, 2017 YW4, 2017 YV4, 2017 YT4, 2017 YR4, 2017 YQ4, 2017 YP4, 2017 YO4
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2017-Y99 -- 503941
L01Visnjan Obs., 1 in MPEC 2017-Y101 -- 2017 YP4
718Wiggins Obs. in Utah, 1 in MPEC 2017-Y101 -- 2017 YP4
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 26 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 SU17JPL Sentry16242069-2117342.7741307e-05-6.31-6.840JPL: Computed at 08:04 today Pacific time based on 34 observations spanning 4.8292 days (2017-Sep-26.44444 to 2017-Oct-01.2736). Diameter approximately 0.008 km. from weighted mean H=28.03.
2017 SS12JPL Sentry16242074-208951.41085e-06-7.08-7.430JPL: Computed at 08:02 today Pacific time based on 90 observations spanning 6.9212 days (2017-Sep-25.23585 to 2017-Oct-02.15703). Diameter approximately 0.013 km. from weighted mean H=27.13.

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 26 December '17

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

2207Updated Traffic Report
2040Grabbed MPEC 2017-Y109 - 2017 YX4 - see above
Grabbed MPEC 2017-Y110 - 2009 EV = 2008 PG1 = 2017 YQ4 - see above
Grabbed MPEC 2017-Y111 - 2017 YY4 - see above
Grabbed MPEC 2017-Y112 - 2017 YZ4 - see above
1940Grabbed MPEC 2017-Y100 - 2017 YO4 - see above
Grabbed MPEC 2017-Y101 - 2017 YP4 - see above
Grabbed MPEC 2017-Y102 - 2017 YQ4 - see above
Grabbed MPEC 2017-Y103 - 2017 YR4 - see above
Grabbed MPEC 2017-Y104 - 2017 YS4 - see above
Grabbed MPEC 2017-Y105 - 2017 YT4 - see above
Grabbed MPEC 2017-Y106 - 2017 YU4 - see above
Grabbed MPEC 2017-Y107 - 2017 YV4 - see above
Grabbed MPEC 2017-Y108 - 2017 YW4 - see above
1624Noted that JPL Sentry has updated its 2017 SS12 risk assessment - see above
Noted that JPL Sentry has updated its 2017 SU17 risk assessment - see above
Grabbed MPEC 2017-Y99 - Daily Orbit Update - see above