Contents  on 30 March '18

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 March '18

Six objects reported inside ten LD

There are six asteroids reported within ten lunar distances (LD) of our home world today. Nearest is newly announced risk-listed intruder 2018 FK5, which flies through the Earth-Moon system, starting the day at 1.48 LD from Earth, passing the Moon at 0.61 LD at 0603 UTC and us at 0.39 LD at 1327 UTC, and ending the day out at 1.19 LD from our planet.

Neighborhood Traffic - sorted by Earth passage distance, grouped by 1.0, 2.41, 5.0 & 10.0 LD boundaries
Earth passage I D ~Size Distance today  Inside ten LD Notes
0.39 LD today 2018 FK5 7 m  0.39 LD March 26 - April 3 intruder today, Moon closest 0.61 LD at 0603
UTC, Earth closest at 1327 UTC, risk - MPEC
4.0   LD April 2* 2004 FG29 21 m  9.5 from 12.6 LD today - April 5 EPU +/- 1.03 hours*, enters ten LD
4.88 LD yesterday 2018 FB 52 m  4.88 to 5.31 LD March 25 - April 3 DOU
5.63 LD March 25 2018 FQ1 14 m  7.87 to 8.86 LD March 19 - April 1 NHATS target
6.23 LD April 1 2018 EM4 30 m  6.46 from 6.96 LD March 26 - April 6 NHATS target
7.69 LD March 28 2018 FO4 11 m  7.86 to 8.27 LD March 24 - April 2 NHATS target

This report was generated at 1820 UTC with the discovery of passing risk-listed intruder 2018 FK5 (MPEC) and with follow-up in today's DOU MPEC for outbound 2018 FB, departed 2018 FW1, and distant 450894 2008 BT18, along with astrometry from last month for 2017 VR12.

Approaching Traffic - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
9.73 LD April 5 2018 FW4 33 m  16.54 from 18.75 LD April 4 - 5
9.24 LD April 14 2014 UR 16 m  16.85 from 17.65 LD April 10 - 18 NHATS target
6.2   LD May 8* 2016 JQ5 8 m  100.4 from 103.6 LD May 4 - 11 EPU +/- 14.00 hours*
9.65 LD May 7 1999 FN19 112 m  46.79 from 47.97 LD May 5 - 9 radar/NHATS target
6.48 LD May 9 388945 2008 TZ3 282 m  88.12 from 90.73 LD May 5 - 13
9.50 LD May 29 68347 2001 KB67 371 m  222.39 from 227.65 LD May 28 - 30 radar target
5.6   LD June 10* 2018 EJ4 181 m  93.8 from 95.2 LD June 4 - 16 EPU +/- 1.22 hours*, radar/NHATS target
8.96 LD June 11 2015 DP155 162 m  59.49 from 60.21 LD June 6 - 15 NHATS target
* EPU = Earth passage uncertainty



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 temporal distances are derived by A/CC from JPL Horizons data. "LD*" indicates some uncertainty in object passage time and distance. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

Radar Astrometry  on 30 March '18

Radar observation of two 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 2325 UTC when the database was dated 30 March


Data update noted at 2358 UTC when the database was dated 30 March

NEOCP Activity  on 30 March '18

The MPC's NEO Confirmation Page has 15 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had fifteen objects listed. Of these, eight were "one nighters." So far The Tracking News has counted a total of seventeen 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 March '18

Minor Planet Electronic Circulars

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


<< DOU on 30 Mar. '18 >>  MPEC 2018-F158 - "12:05 UT" - Daily Orbit Update


MPEC 2018-F157 - "01:13 UT" - 2016 SW50


MPEC 2018-F156 - "01:11 UT" - 2016 PA101


MPEC 2018-F155 - "01:02 UT" - 2014 WM517


MPEC 2018-F154 - "00:59 UT" - 2014 WL517

Observers  on 30 March '18

Fourteen observers appear in today's MPECs.

CodeObserver / observatory
834AAAA Buenos Aires Obs. in Argentina, 1 in MPEC 2018-F158 -- 138847
251Arecibo in Puerto Rico, 1 in radar -- 2018 DH1
T05ATLAS Haleakala in Hawaii, 10 in MPEC 2018-F158 -- 2018 FF2, 2018 DX3, 2005 JD46, 85628, 474574, 363599, 163243, 141484, 1981, 1627
T08ATLAS Mauna Loa in Hawaii, 8 in MPEC 2018-F158 -- 475967, 450894, 163691, 152931, 11066, 3752, 1866, 1864
160Castelmartini Obs. in Italy, 5 in MPEC 2018-F158 -- 2018 DX3, 333888, 9856, 6053, 3122
703Catalina Sky Survey (CSS) in Arizona, 7 in MPEC 2018-F158 -- 85628, 474574, 337084, 25916, 212359, 15745, 1627
W847David Gerdes in Michigan via DECam in Chile, 4 in MPECs 2018-F154, 2018-F155, 2018-F156 & 2018-F157 -- 2016 SW50, 2016 PA101, 2014 WM517, 2014 WL517
253Goldstone DSS-14 70m antenna in southern California, 2 in radar -- 2018 DH1, 276033
G96Mt. Lemmon Survey (MLS) in Arizona, 17 in MPEC 2018-F158 -- 2018 FW1, 2018 FN4, 2018 FL4, 2018 FB1, 2018 EQ4, 2015 FM34, 2012 PN28, 481817, 307918, 25916, 24445, 220839, 212359, 162998, 162168, 159533, 15745
K74Muensterschwarzach Obs. in Germany, 1 in MPEC 2018-F158 -- 2018 FB
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2018-F158 -- 2015 FM34
247roving observer, 1 in MPEC 2018-F158 -- 2017 VR12
I52Steward Obs. Mt. Lemmon Station in Arizona, 3 in MPEC 2018-F158 -- 2018 CX13, 2017 XH62, 2015 FM34
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 2 in MPEC 2018-F158 -- 2010 LL68, 504827
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 30 March '18

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
2018 FK5NEODyS15502033-2117173.43e-06-7.25-7.520NEODyS: "Based on 33 optical observations (of which 0 are rejected as outliers) from 2018-03-28.223 to 2018-03-29.974."
JPL Sentry04372087-211023.72e-06-7.24-7.510JPL: Computed at 18:39 March 29th Pacific time based on 33 observations spanning 1.7506 days (2018-Mar-28.22211 to 2018-Mar-29.97275). Diameter approximately 0.007 km. from weighted mean H=28.28.
2018 FJ5NEODyS15502032-2118522.19e-07-3.67-4.62n/aNEODyS: "Based on 33 optical observations (of which 1 are rejected as outliers) from 2018-03-24.431 to 2018-03-28.263."
2018 FE4NEODyS15502079-2118201.16e-06-5.77-6.47n/aNEODyS: "Based on 28 optical observations (of which 1 are rejected as outliers) from 2018-03-20.460 to 2018-03-29.246."

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 March '18

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

2358Noted Radar Astrometry database update - see above
2325Noted Radar Astrometry database update - see above
1820Generated Traffic Report
1550Noted that NEODyS has updated its 2018 FE4 risk assessment - see above
Noted that NEODyS has posted 2018 FJ5 as an impact risk - see above
Noted that NEODyS has posted 2018 FK5 as an impact risk - see above
Grabbed MPEC 2018-F158 - Daily Orbit Update - see above
0437Noted that JPL Sentry has posted 2018 FK5 as an impact risk - see above
Grabbed MPEC 2018-F154 - 2014 WL517 - see above
Grabbed MPEC 2018-F155 - 2014 WM517 - see above
Grabbed MPEC 2018-F156 - 2016 PA101 - see above
Grabbed MPEC 2018-F157 - 2016 SW50 - see above