Contents  on 21 October '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 21 October '17

Sixteen objects reported inside ten LD

Sixteen minor planets are reported traveling within ten lunar distances (LD) of our planet today. Closest is risk-listed intruder 2017 TD6, which is outbound from 2.52 to 4.52 LD.

Earth passage I D ~Size Distance Today  Notes
0.50 LD Oct. 192017 TD6 13 m  2.52 to 4.52 LD intruder, risk - DOU
1.19 LD Oct. 172017 UA 7 m  6.09 to 7.84 LD
1.34 LD Oct. 172017 TE5 22 m  8.74 to 11.15 LD exits ten LD
1.97 LD Oct. 162017 UU1 14 m  5.44 to 6.64 LD
2.76 LD Oct. 192017 UJ 26 m  5.42 to 7.86 LD
3.37 LD tomorrow2017 TV5 14 m  3.45 from 4.63 LD DOU
4.18 LD Oct. 152017 TK4 10 m  6.30 to 7.02 LD DOU
4.27 LD yesterday2017 UG 11 m  4.48 to 5.68 LD
4.56 LD Oct. 182017 TX5 22 m  7.00 to 8.87 LD
4.80 LD today2017 TG4 49 m  4.80 LD Earth closest at 1506 UTC
4.94 LD today2017 UH1 21 m  4.94 LD Earth closest at 0708 UTC
5.50 LD tomorrow2017 TQ5 11 m  5.56 from 5.88 LD
5.77 LD tomorrow171576 1999 VP11 645 m  6.17 from 9.04 LD
6.64 LD Oct. 192017 TA6 16 m  6.73 to 6.95 LD risk
6.95 LD today2017 UM1 25 m  6.95 LD Earth closest at 1747 UTC - DOU
7.46 LD tomorrow2017 US 23 m  7.50 from 7.66 LD risk
Approaching
8.66 LD Nov. 17444584 2006 UK 309 m  < 10 LD Nov. 16

This report was generated at 1745 UTC follow-up in today's DOU MPEC for four objects active in the above traffic table and for four departed objects: 2017 UE, 2017 UD, 2017 TH4, and intruder and NHATS/radar target 2012 TC4, as well as distant 2003 UV11, plus astrometry from March for NHATS target 2017 FR.



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 an object that has come within ten LD since A/CC began these traffic reports (2007) but is not now so close. Object 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 21 October '17

The MPC's NEO Confirmation Page has 62 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 62 objects listed. Of these, 37 were "one nighters." So far The Tracking News has counted a total of 75 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 21 October '17

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 21 Oct. '17 >>  MPEC 2017-U153 - "12:09 UT" - Daily Orbit Update


MPEC 2017-U152 - "11:59 UT" - 2015 RA83

Observers  on 21 October '17

A total of 24 observers appear in today's MPECs.

CodeObserver / observatory
T08ATLAS Mauna Loa in Hawaii, 12 in MPEC 2017-U153 -- 2017 RL, 2014 YC15, 2014 UR116, 2004 SS, 99907, 500749, 39572, 190208, 17182, 153415, 138205, 3200
073Bucharest Obs. in Romania, 1 in MPEC 2017-U153 -- 2003 UV11
160Castelmartini Obs. in Italy, 6 in MPEC 2017-U153 -- 2017 SY20, 2010 SA12, 2008 MH1, 96744, 85709, 65679
703Catalina Sky Survey (CSS) in Arizona, 3 in MPEC 2017-U153 -- 497176, 420302, 415029
K05Eden Obs., 1 in MPEC 2017-U153 -- 3122
J04ESA Optical Ground Station in the Canary Islands, 1 in MPEC 2017-U152 -- 2015 RA83
K88GINOP-KHK in Hungary, 1 in MPEC 2017-U153 -- 2017 UE
W19Kalamazoo Obs. in Michigan, 2 in MPEC 2017-U153 -- 500749, 498548
246KLENOT in the Czech Republic, 2 in MPEC 2017-U153 -- 2017 TN2, 2017 TH6
H01Magdalena Ridge Obs. in New Mexico, 1 in MPEC 2017-U153 -- 2012 TC4
C94MASTER-II Tunka in Russia, 2 in MPEC 2017-U153 -- 495511, 8037
474Mt. John Obs. in New Zealand, 2 in MPEC 2017-U153 -- 2017 UM1, 2017 TD6
G96Mt. Lemmon Survey (MLS) in Arizona, 8 in MPEC 2017-U153 -- 2011 VQ5, 2001 UF18, 85839, 435302, 329520, 20086, 19764, 2212
F51Pan-STARRS 1 (PS1) in Hawaii, 4 in MPEC 2017-U153 -- 2017 TN2, 2014 UA192, 441825, 137799
D29Purple Mtn. Obs. Xuyi Station in China, 7 in MPEC 2017-U153 -- 2017 RK1, 416584, 142464, 141670, 5189, 5143, 3288
Y28Sertao de Itaparica Obs. in Brazil, 1 in MPEC 2017-U152 -- 2015 RA83
G40!M. Kumrucu-Lohmiller in Massachusetts via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2017-U153 -- 496005
691Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2017-U153 -- 496816
291Spacewatch 1.8m telescope in Arizona, 5 in MPEC 2017-U153 -- 2017 UL1, 2017 SV19, 2017 SL17, 2017 SG14, 2014 JN57
W34Squirrel Valley Obs. in North Carolina, 1 in MPEC 2017-U153 -- 503293
I52Steward Obs. Mt. Lemmon Station in Arizona, 11 in MPEC 2017-U153 -- 2017 UQ, 2017 UD, 2017 UC, 2017 TY4, 2017 TX3, 2017 TV5, 2017 TL4, 2017 TK6, 2017 TH4, 2017 TF4, 2017 SM19
926Tenagra II Obs. in Arizona, 3 in MPEC 2017-U153 -- 2017 US1, 2017 TK4, 2017 TD4
W33Transit Dreams Obs., 2 in MPEC 2017-U153 -- 3361, 3122
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2017-U153 -- 2017 FR
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 21 October '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 UL1JPL Sentry1502R E M O V E DJPL: Risk listing removed at 1447 UTC today
NEODyS1632211011.13e-10-9.99-9.990NEODyS: "Based on 21 optical observations (of which 1 are rejected as outliers) from 2017-10-16.390 to 2017-10-21.341."
2017 UFNEODyS15022050-206626.08e-08-8.24-8.320NEODyS: "Based on 26 optical observations (of which 6 are rejected as outliers) from 2017-10-16.262 to 2017-10-19.260."
2017 TD6JPL Sentry1530R E M O V E DJPL: Risk listing removed at 1506 UTC today
NEODyS1502208116.5e-09-9.44-9.440NEODyS: "Based on 79 optical observations (of which 1 are rejected as outliers) from 2017-10-11.413 to 2017-10-18.554."
2017 TA6NEODyS15022075-2116136.65e-06-6.35-6.690NEODyS: "Based on 34 optical observations (of which 1 are rejected as outliers) from 2017-10-15.438 to 2017-10-19.510."
2017 TT3NEODyS15022089-211422.28e-08-8.36-8.360NEODyS: "Based on 26 optical observations (of which 1 are rejected as outliers) from 2017-10-10.438 to 2017-10-19.920."

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 21 October '17

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

1745Generated Traffic Report
1632Noted that NEODyS has updated its 2017 UL1 risk assessment - see above
1530Noted that JPL Sentry has removed 2017 TD6 as an impact risk - see above
1502Noted that NEODyS has updated its 2017 TA6 risk assessment - see above
Noted that NEODyS has updated its 2017 TD6 risk assessment - see above
Noted that NEODyS has updated its 2017 TT3 risk assessment - see above
Noted that NEODyS has updated its 2017 UF risk assessment - see above
Noted that JPL Sentry has removed 2017 UL1 as an impact risk - see above
Grabbed MPEC 2017-U152 - 2015 RA83 - see above
Grabbed MPEC 2017-U153 - Daily Orbit Update - see above