Contents  on 20 January '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 20 January '17

One object reported inside ten LD

There is one transient natural object reported moving inside ten lunar distances (LD) of our home world today. NHATS target 2016 YC8 leaves our ten-LD traffic reporting "bubble," slipping off from 9.85 to 10.35 LD. No other object is presently known to be coming that close until 2005 VL1, a returning (and as yet unrecovered) risk-listed NHATS target that arrives on February 1st.

This report was generated at 2014 UTC with optical follow-up in today's DOU MPEC for departed 2017 AJ13 and NHATS target 2017 AG5, and with radar follow-up from December for 2016 XK18 and from November for 2016 UY56.

Notes: Ten times the distance to the Moon (ten LD) has no astronomical importance but is a useful boundary for reporting on transient natural objects that approach the actually significant 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 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.

Radar Astrometry  on 20 January '17

Radar observation of three objects

The JPL Solar System Dynamics Group Radar Astrometry database has added or updated the following small-body radar observing work:

Data update noted at 0203 UTC when the database was dated 19 Jan.

Data update noted at 2358 UTC when the database was dated 20 Jan.

NEOCP Activity  on 20 January '17

The MPC's NEO Confirmation Page has 68 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 68 objects listed. Of these, 30 were "one nighters." So far The Tracking News has counted a total of 69 listings on the NEOCP today.

New MPECs  on 20 January '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.

MPEC 2017-B26 - "14:07 UT" - 2015 BR4

<< DOU on 20 Jan. '17 >>  MPEC 2017-B25 - "13:02 UT" - Daily Orbit Update

Observers  on 20 January '17

A total of 27 observers appear in today's MPECs.

CodeObserver / observatory
251Arecibo in Puerto Rico, 1 in radar -- 481817
160Castelmartini Obs. in Italy, 7 in MPEC 2017-B25 -- 2016 RP33, 96590, 378610, 220124, 5836, 3352, 2102
K88GINOP-KHK, 2 in MPEC 2017-B25 -- 2017 BK, 2017 AM4
253Goldstone DSS-14 70m antenna in southern California, 3 in radar -- 2016 XK18, 2016 UY56, 481817
J95Great Shefford Obs. in England, 1 in MPEC 2017-B25 -- 2017 AJ13
Q60ISON Siding Spring Obs. in New South Wales, 1 in MPEC 2017-B25 -- 1036
950.Ovidiu Vaduvescu via La Palma in the Canary Islands, 1 in MPEC 2017-B25 -- 2001 QE34
W86LCOGT Cerro Tololo B in Chile, 2 in MPEC 2017-B25 -- 265482, 192559
W87LCOGT Cerro Tololo C in Chile, 1 in MPEC 2017-B25 -- 192559
K91LCOGT Sutherland A in South Africa, 2 in MPEC 2017-B25 -- 265482, 192559
K92LCOGT Sutherland B in South Africa, 1 in MPEC 2017-B25 -- 192559
Z21LCOGT Tenerife Aqawan A#1 in the Canary Islands, 1 in MPEC 2017-B25 -- 2001 QE34
K38M57 Obs. in Italy, 1 in MPEC 2017-B25 -- 2016 YN4
Z22MASTER IAC Obs. in the Canary Islands, 1 in MPEC 2017-B25 -- 108519
C94MASTER-II Tunka in Russia, 3 in MPEC 2017-B25 -- 2014 EW24, 2014 AD17, 13651
B67Mirasteilas Obs. in Switzerland, 4 in MPEC 2017-B25 -- 2017 AF5, 2016 PR8, 2016 NL15, 2016 LM8
474Mt. John Obs. in New Zealand, 3 in MPEC 2017-B25 -- 2017 AQ19, 2017 AP13, 2017 AC5
G96Mt. Lemmon Survey (MLS) in Arizona, 17 in MPEC 2017-B25 -- 2016 XH2, 2016 LM8, 2014 ME19, 2013 PV2, 2012 BX13, 2005 TF, 2002 XN14, 265661, 194268, 187040, 162000, 155334, 153220, 153201, 5836, 4179, 1862
K74Muensterschwarzach Obs. in Germany, 1 in MPEC 2017-B25 -- 2017 AF5
A24New Millennium Obs. in Italy, 13 in MPEC 2017-B25 -- 2016 RP33, 2016 LX48, 68950, 480004, 479325, 470510, 452389, 16834, 162269, 154244, 7341, 1943, 1863
J69North Obs. in England, 1 in MPEC 2017-B25 -- 2017 BK
G34Oberfrauendorf Obs. in Germany, 1 in MPEC 2017-B25 -- 54789
K63Pascoli Obs. in Italy, 2 in MPEC 2017-B25 -- 4179, 1627
D29Purple Mtn. Obs. Xuyi Station in China, 14 in MPEC 2017-B25 -- 2017 AG5, 2017 AF5, 2016 LM8, 2011 WO41, 2001 QE34, 97725, 481904, 36017, 34613, 25916, 232382, 22753, 152560, 9172
L04ROASTERR-1 in Romania, 1 in MPEC 2017-B25 -- 2001 QE34
691Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2017-B25 -- 2016 PZ66
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2017-B26 -- 2015 BR4
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 20 January '17

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS and JPL 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 JPL NEO Program Sentry and NEODyS CLOMON2 risk pages.





Notes for Today's Latest Risk Assessments
2017 AM4JPL Sentry18052024-2112129.0e-07-1.92-1.920JPL: "Analysis based on 30 observations spanning 16.441 days (2017-Jan-03.5207 to 2017-Jan-19.96134)." Diameter approximately 0.510 km. from mean, weighted H=19.1.
NEODyS18052024-2115145.76e-07-2.13-2.130NEODyS: "Based on 30 optical observations (of which 0 are rejected as outliers) from 2017-01-03.522 to 2017-01-19.962."
2016 YM4NEODyS1805209414.78e-08-5.99-5.990NEODyS: "Based on 53 optical observations (of which 0 are rejected as outliers) from 2016-12-24.192 to 2017-01-07.278."

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 20 January '17

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

2358Noted Radar Astrometry database update - see above
2014Generated Traffic Report
1805Noted that NEODyS has reposted 2016 YM4 as an impact risk - see above
Noted that JPL Sentry has updated its 2017 AM4 risk assessment - see above
Noted that NEODyS has updated its 2017 AM4 risk assessment - see above
1710Grabbed MPEC 2017-B25 - Daily Orbit Update - see above
Grabbed MPEC 2017-B26 - 2015 BR4 - see above
0203Noted Radar Astrometry database update - see above