Contents  on 25 May '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 25 May '18

Six objects reported inside ten LD

There are six planetesimals known to be less than ten lunar distances (LD) from our planet today. The nearest of these is intruder 2018 KW1, which is outbound from 2.41 to 3.96 LD.

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 May 23 2018 KW1 4 m  2.41 to 3.96 LD May 17 - 29 intruder, NHATS target
2.05 LD May 22 2018 KS 9 m  5.27 to 6.88 LD May 16 - 27 NHATS target
2.24 LD May 21 2018 KF1 25 m  7.34 to 9.18 LD May 16 - 26 DOU
2.48 LD May 23 2018 KT2 15 m  4.52 to 6.22 LD May 18 - 28 NEW - MPEC
3.13 LD May 21 2018 KU2 15 m  6.70 to 8.23 LD May 15 - 27 NEW - MPEC
6.10 LD May 29 2018 KN2 27 m  8.97 from 10.37 LD today - June 3 enters ten LD

This report was generated at 1751 UTC with the discoveries of outbound objects 2018 KU2 (MPEC) and 2018 KT2 (MPEC), and with follow-up in today's DOU MPEC for three objects in the accompanying active traffic tables and for three departed objects: 1999 FN19, 2018 KO1, and risk-listed 2018 JN.

Approaching Traffic - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
9.50 LD May 29 68347 2001 KB67 371 m  13.32 from 15.58 LD May 28 - 30 radar target
5.56 LD June 10 2018 EJ4 186 m  22.54 from 23.86 LD June 4 - 16 radar/NHATS target - DOU
8.96 LD June 11 2015 DP155 162 m  18.13 from 18.95 LD June 6 - 15 NHATS target - DOU



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 25 May '18

The MPC's NEO Confirmation Page has 22 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 22 objects listed. Of these, eight were "one nighters." So far The Tracking News has counted a total of 27 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 25 May '18

Minor Planet Electronic Circulars

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


MPEC 2018-K90 - "14:51 UT" - 2018 KR2


MPEC 2018-K89 - "14:17 UT" - 2018 KU2


MPEC 2018-K88 - "14:12 UT" - 2018 KT2


MPEC 2018-K87 - "14:08 UT" - 2018 KS2


<< DOU on 25 May '18 >>  MPEC 2018-K86 - "12:05 UT" - Daily Orbit Update


MPEC 2018-K85 - "10:27 UT" - 2014 FX


MPEC 2018-K84 - "10:16 UT" - 2015 WG9

Observers  on 25 May '18

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

CodeObserver / observatory
E23Arcadia Obs. in New South Wales, 1 in MPEC 2018-K89 -- 2018 KU2
T05ATLAS Haleakala in Hawaii, 4 in MPECs 2018-K86 & 2018-K90 -- 2018 KR2, 25916, 164121, 162168
T08ATLAS Mauna Loa in Hawaii, 5 in MPECs 2018-K86 & 2018-K90 -- 2018 KR2, 2018 EJ4, 2015 DP155, 144332, 138847
K46Bamberg Obs. in Germany, 1 in MPEC 2018-K86 -- 1627
X74Campo dos Amarais Obs., 1 in MPEC 2018-K86 -- 67367
703Catalina Sky Survey (CSS) in Arizona, 21 in MPECs 2018-K86, 2018-K88 & 2018-K89 -- 2018 KU2, 2018 KT2, 2018 BY2, 2005 JY80, 1999 LK1, 88254, 87311, 85628, 511523, 36183, 25916, 18109, 164121, 163243, 154268, 152637, 11500, 100085, 6569, 4183, 1685
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 2 in MPECs 2018-K84 & 2018-K85 -- 2015 WG9, 2014 FX
734Farpoint Obs. in Kansas, 1 in MPEC 2018-K87 -- 2018 KS2
H15ISON New Mexico Obs. in New Mexico, 1 in MPEC 2018-K86 -- 467309
W89LCO Cerro Tololo Aqawan A#1 in Chile, 1 in MPEC 2018-K86 -- 467309
T04LCO Haleakala OGG B#2 in Hawaii, 1 in MPEC 2018-K86 -- 2018 EJ4
H01Magdalena Ridge Obs. in New Mexico, 1 in MPEC 2018-K87 -- 2018 KS2
932McCarthy Obs. in Connecticut, 1 in MPEC 2018-K86 -- 2018 JK3
G84Mt. Lemmon SkyCenter in Arizona, 1 in MPEC 2018-K86 -- 16834
G96Mt. Lemmon Survey (MLS) in Arizona, 17 in MPECs 2018-K86 & 2018-K87 -- 2018 KS2, 2018 JY1, 2010 MS1, 2001 SC170, 54686, 516641, 514652, 468909, 466508, 398188, 37655, 335746, 164201, 162980, 139289, 138937, 138359
I41Palomar Transient Factory in southern California, 1 in MPEC 2018-K86 -- 2018 JA
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPEC 2018-K86 -- 288807, 3752
F52Pan-STARRS 2 in Hawaii, 1 in MPEC 2018-K86 -- 138847
204Schiaparelli Obs. in Italy, 2 in MPECs 2018-K88 & 2018-K89 -- 2018 KU2, 2018 KT2
691Spacewatch 0.9m telescope in Arizona, 10 in MPECs 2018-K86, 2018-K88 & 2018-K90 -- 2018 KT2, 2018 KR2, 2018 KQ1, 2018 KO1, 2018 KL2, 2018 KG1, 2018 JV2, 2018 JQ1, 1999 LW1, 1999 FN19
291Spacewatch 1.8m telescope in Arizona, 8 in MPEC 2018-K86 -- 2018 KN1, 2018 KM2, 2018 KC2, 2018 JN, 2018 JC2, 2018 EQ4, 2017 NK, 2014 NE3
I52Steward Obs. Mt. Lemmon Station in Arizona, 18 in MPECs 2018-K86, 2018-K87, 2018-K88, 2018-K89 & 2018-K90 -- 2018 KU2, 2018 KU1, 2018 KT2, 2018 KS2, 2018 KR2, 2018 KR, 2018 KQ1, 2018 KP, 2018 KO1, 2018 KM1, 2018 KL1, 2018 KJ1, 2018 KH1, 2018 KD1, 2018 KC2, 2018 JJ3, 2018 JD5, 2018 EM2
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 2 in MPEC 2018-K86 -- 2018 KF1, 2018 JN
C51WISE in Earth polar orbit, 3 in MPEC 2018-K86 -- 2018 HH, 2005 JY80, 424482
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 25 May '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 KF1JPL Sentry1608R E M O V E DJPL: Risk listing removed at 1417 UTC today
2018 JC2JPL Sentry16082050-205011.449e-10-8.65-8.650JPL: Computed at 07:12 today Pacific time based on 82 observations spanning 14.911 days (2018-May-09.32052 to 2018-May-24.23141). Diameter approximately 0.094 km. from weighted mean H=22.79.
NEODyS1608205013.84e-10-8.17-8.170NEODyS: "Based on 80 optical observations (of which 0 are rejected as outliers) from 2018-05-09.321 to 2018-05-24.232."
2018 JNJPL Sentry16082100-211221.6945e-06-6.18-6.460JPL: Computed at 07:16 today Pacific time based on 143 observations spanning 20.012 days (2018-May-05.42349 to 2018-May-25.43516). Diameter approximately 0.033 km. from weighted mean H=25.08.
NEODyS1608210012.14e-06-6.05-6.050NEODyS: "Based on 135 optical observations (of which 1 are rejected as outliers) from 2018-05-05.424 to 2018-05-24.346."
2018 HJ2NEODyS16082085-211431.09e-05-5.16-5.190NEODyS: "Based on 103 optical observations (of which 0 are rejected as outliers) from 2018-04-23.412 to 2018-05-23.461."

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 25 May '18

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

1751Updated Traffic Report
1608Noted that NEODyS has updated its 2018 HJ2 risk assessment - see above
Noted that JPL Sentry has updated its 2018 JC2 risk assessment - see above
Noted that NEODyS has reposted 2018 JC2 as an impact risk - see above
Noted that JPL Sentry has updated its 2018 JN risk assessment - see above
Noted that NEODyS has updated its 2018 JN risk assessment - see above
Noted that JPL Sentry has removed 2018 KF1 as an impact risk - see above
Grabbed MPEC 2018-K84 - 2015 WG9 - see above
Grabbed MPEC 2018-K85 - 2014 FX - see above
Grabbed MPEC 2018-K86 - Daily Orbit Update - see above
Grabbed MPEC 2018-K87 - 2018 KS2 - see above
Grabbed MPEC 2018-K88 - 2018 KT2 - see above
Grabbed MPEC 2018-K89 - 2018 KU2 - see above
Grabbed MPEC 2018-K90 - 2018 KR2 - see above