Contents  on 30 November '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 30 November '17

Ten objects reported inside ten LD

Ten planetesimals are known to be inside ten lunar distances (LD) of Earth today. Nearest is 2017 WF16, which is outbound from 3.80 to 4.09 LD.

Earth passage I D ~Size Distance Today  Notes
1.68 LD Nov. 242017 WL28 10 m  9.06 to 10.78 LD NEW, exits ten LD - MPEC
1.74 LD Nov. 262017 WH13 16 m  9.80 to 12.33 LD exits ten LD
2.02 LD Nov. 252017 VY13 18 m  9.90 to 12.23 LD exits ten LD
3.67 LD Dec. 22008 WM61 15 m  3.99 from 4.50 LD NHATS target
3.72 LD yesterday2017 WF16 6 m  3.80 to 4.09 LD
4.45 LD Nov. 282017 WD28 25 m  5.55 to 7.72 LD
6.39 LD today2017 WH2 46 m  6.39 LD Earth closest at 1101 UTC - DOU
7.37 LD yesterday2017 WN15 36 m  8.21 to 10.86 LD exits ten LD
7.78 LD Nov. 282017 WK1 14 m  8.51 to 9.38 LD
8.73 LD Nov. 272017 WK15 15 m  9.46 to 10.03 LD exits ten LD

This report was generated at 1851 UTC with the discovery of 2017 WL28 (MPEC) just as it leaves our ten-LD traffic reporting "bubble," and with follow-up in today's DOU MPEC for 2017 WH2, which comes its closest to our planet this time around -- 6.39 LD at 1101 UTC, plus astrometry from mid-month for 496817 1989 VB

Approaching (sorted by 10-LD bubble entry date)
9.45 LD Dec. 52017 WS13 40 m  < 10 LD Dec. 4
3.35 LD Dec. 142006 XY 54 m  < 10 LD Dec. 5, NHATS target
3.44 LD Dec. 92017 WV12 24 m  < 10 LD Dec. 5
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., risk, comet nucleus?
7.6   LD Dec. 242017 WZ14 31 m  < 10 LD Dec. 18, uncertainty +/- 54 mins., radar 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



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 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 30 November '17

The MPC's NEO Confirmation Page has 43 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 43 objects listed. Of these, fifteen were "one nighters." So far The Tracking News has counted a total of 46 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 30 November '17

Minor Planet Electronic Circulars

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


MPEC 2017-W219 - "17:05 UT" - 2017 WL28


MPEC 2017-W218 - "16:53 UT" - 2017 WK28


MPEC 2017-W217 - "16:49 UT" - 2017 WJ28


<< DOU on 30 Nov. '17 >>  MPEC 2017-W216 - "13:10 UT" - Daily Orbit Update

Observers  on 30 November '17

Fourteen observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 1 in MPEC 2017-W218 -- 2017 WK28
160Castelmartini Obs. in Italy, 3 in MPEC 2017-W216 -- 2017 SO17, 2017 SL2, 496817
V06Catalina Sky Survey Kuiper Telescope (CSS-Kuiper) in Arizona, 4 in MPECs 2017-W216, 2017-W217, 2017-W218 & 2017-W219 -- 2017 WL28, 2017 WK28, 2017 WJ28, 2017 WD16
J95Great Shefford Obs. in England, 4 in MPECs 2017-W216, 2017-W217 & 2017-W218 -- 2017 WK28, 2017 WJ28, 2017 WH28, 2017 WH2
130Lumezzane Obs. in Italy, 14 in MPEC 2017-W216 -- 2017 WV13, 2017 WF13, 2017 VM2, 2007 VW137, 2007 VL8, 1998 WP7, 505093, 500749, 495858, 438430, 323300, 154991, 154589, 5189
K95MASTER-II Sutherland in South Africa, 1 in MPEC 2017-W216 -- 3752
G96Mt. Lemmon Survey (MLS) in Arizona, 3 in MPECs 2017-W217, 2017-W218 & 2017-W219 -- 2017 WL28, 2017 WK28, 2017 WJ28
J69North Obs. in England, 2 in MPEC 2017-W216 -- 2017 VM2, 140158
C23Olmen Obs. in Belgium, 1 in MPEC 2017-W216 -- 3200
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPECs 2017-W217 & 2017-W219 -- 2017 WL28, 2017 WJ28
Z38Picoto Obs., 2 in MPEC 2017-W216 -- 88188, 17511
V78Spirit Marsh Obs. in Minnesota, 1 in MPEC 2017-W216 -- 3200
I52Steward Obs. Mt. Lemmon Station in Arizona, 3 in MPECs 2017-W217, 2017-W218 & 2017-W219 -- 2017 WL28, 2017 WK28, 2017 WJ28
L01Visnjan Obs., 1 in MPEC 2017-W218 -- 2017 WK28
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 30 November '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
2007 YMJPL Sentry19032019-21152504.3780822e-06-5.81-6.690JPL: Computed at 20:16 April 8th Pacific time based on 12 observations spanning .12805 days (2007-Dec-17.39661 to 2007-Dec-17.52466). Diameter approximately 0.018 km. from weighted mean H=26.34.

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 30 November '17

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

1903Noted that JPL Sentry has updated its 2007 YM risk assessment - see above
1851Generated Traffic Report
1707Grabbed MPEC 2017-W217 - 2017 WJ28 - see above
Grabbed MPEC 2017-W218 - 2017 WK28 - see above
Grabbed MPEC 2017-W219 - 2017 WL28 - see above
1630Grabbed MPEC 2017-W216 - Daily Orbit Update - see above