Contents  on 4 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 4 December '17

Three objects reported inside ten LD

There are three asteroidal objects reported inside ten lunar distances (LD) of Earth today. Nearest is 2008 WM61, outbound from 3.99 to 4.51 LD.

Earth passage I D ~Size Distance Today  Notes
3.67 LD Dec. 22008 WM61 15 m  3.99 to 4.51 LD NHATS target
3.72 LD Nov. 292017 WF16 6 m  5.83 to 6.56 LD NHATS target
9.45 LD tomorrow2017 WS13 40 m  9.56 from 10.25 LD enters ten LD
Approaching (sorted by 10-LD bubble entry date)
3.35 LD Dec. 142006 XY 54 m  < 10 LD tomorrow, NHATS target
3.44 LD Dec. 92017 WV12 24 m  < 10 LD tomorrow
9.71 LD Dec. 142015 XX169 11 m  < 10 LD Dec. 12, NHATS target
3.8   LD Dec. 172017 VT14 100 m  < 10 LD Dec. 13, uncertainty +/- 40 mins., radar target, risk, comet nucleus?
7.6   LD Dec. 242017 WZ14 31 m  < 10 LD Dec. 18, uncertainty +/- 54 mins., radar/NHATS target
3.7   LD Feb. 242017 DR109 10 m  < 10 LD Feb. 18, uncertainty +/- 30 mins., NHATS target
3.7   LD March 72017 VR12 268 m  < 10 LD Feb. 28, uncertainty +/- 1.2667 hours, radar/NHATS target

This report was generated at 1742 UTC with follow-up in today's DOU MPEC for departed 2017 VC.

Note:  JPL has six objects lined up for radar observation this month, but needs further optical follow-up for 2017 QL33 and especially for 2017 WZ14, 2017 WX12, and 2017 VT14, which speculation has as a possible small inactive comet nucleus.

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 4 December '17

The MPC's NEO Confirmation Page has 37 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 37 objects listed. Of these, twelve were "one nighters." So far The Tracking News has counted a total of 40 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 4 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 4 Dec. '17 >>  MPEC 2017-X10 - "13:11 UT" - Daily Orbit Update

Observers  on 4 December '17

Seven observers appear in today's MPEC.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 18 in MPEC 2017-X10 -- 2017 WV13, 2017 WP1, 2017 WL1, 2017 WH15, 2017 WG2, 2017 VU14, 2017 VK1, 2017 VC, 2017 UZ42, 2017 UZ4, 2017 SS19, 2017 SO17, 2017 NL6, 2014 YP15, 85818, 505178, 338176, 154589
T08ATLAS Mauna Loa in Hawaii, 1 in MPEC 2017-X10 -- 475967
130Lumezzane Obs. in Italy, 2 in MPEC 2017-X10 -- 2014 JC31, 210012
K95MASTER-II Sutherland in South Africa, 1 in MPEC 2017-X10 -- 87684
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2017-X10 -- 471956
D29Purple Mtn. Obs. Xuyi Station in China, 4 in MPEC 2017-X10 -- 2017 VW13, 496861, 177255, 10165
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2017-X10 -- 2001 JV1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 4 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.





Notes for Today's Latest Risk Assessments
2017 VW13JPL Sentry16302097-209713.821e-07-4.55-4.550JPL: Computed at 07:51 today Pacific time based on 138 observations spanning 17.166 days (2017-Nov-13.64011 to 2017-Nov-30.80635). Diameter approximately 0.250 km. from weighted mean H=20.62.
NEODyS1630209723.98e-07-4.52-4.540NEODyS: "Based on 138 optical observations (of which 6 are rejected as outliers) from 2017-11-13.641 to 2017-11-30.807."

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 4 December '17

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

1742Generated Traffic Report
1630Noted that JPL Sentry has updated its 2017 VW13 risk assessment - see above
Noted that NEODyS has updated its 2017 VW13 risk assessment - see above
Grabbed MPEC 2017-X10 - Daily Orbit Update - see above