Contents  on 1 April '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 1 April '18

Six objects reported inside ten LD

There are six planetesimals reported inside ten lunar distances (LD) of Earth today. Nearest are risk-listed intruder 2018 FK5, which is outbound from 3.68 to 6.21 LD, and not-yet recovered 2004 FG29, calculated to be inbound from 6.6 to 4.4 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 March 30 2018 FK5 7 m  3.68 to 6.21 LD March 26 - April 3 intruder, risk
4.0   LD tomorrow* 2004 FG29 21 m  4.4 from 6.6 LD March 30 - April 5 EPU +/- 1.03 hours*
4.88 LD March 29 2018 FB 54 m  6.30 to 7.65 LD March 25 - April 3 DOU
5.63 LD March 25 2018 FQ1 14 m  9.93 to 11.07 LD March 19 - today NHATS target, exits ten LD
6.23 LD today 2018 EM4 30 m  6.23 LD March 26 - April 6 NHATS target, Earth closest at 0550 UTC
7.69 LD March 28 2018 FO4 11 m  8.87 to 9.64 LD March 24 - tomorrow NHATS target

This report was generated at 2122 UTC with follow-up in today's DOU MPEC for outbound 2018 FB and departed risk-listed intruder 2018 FE3, and with observations from early March of 2018 DH1, 2018 DC and 2017 VR12, which also has had radar observations posted today.

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  12.67 from 14.49 LD April 4 - 5
9.24 LD April 14 2014 UR 16 m  15.27 from 16.05 LD April 10 - 18 NHATS target
6.2   LD May 8* 2016 JQ5 8 m  94.2 from 97.3 LD May 4 - 11 EPU +/- 14.00 hours*
9.65 LD May 7 1999 FN19 112 m  44.45 from 45.62 LD May 5 - 9 radar/NHATS target
6.48 LD May 9 388945 2008 TZ3 282 m  82.97 from 85.53 LD May 5 - 13
9.50 LD May 29 68347 2001 KB67 371 m  212.04 from 217.19 LD May 28 - 30 radar target
5.6   LD June 10* 2018 EJ4 181 m  91.2 from 92.5 LD June 4 - 16 EPU +/- 1.22 hours*, radar/NHATS target
8.96 LD June 11 2015 DP155 162 m  58.06 from 58.77 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. 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 1 April '18

Radar observation of nine 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 0430 UTC when the database was dated 31 March


Data update noted at 0703 UTC when the database was dated 31 March


Data update noted at 1624 UTC when the database was dated 1 April

NEOCP Activity  on 1 April '18

The MPC's NEO Confirmation Page has 13 listings

When last checked at 2359 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had thirteen objects listed. Of these, four were "one nighters." So far The Tracking News has counted a total of fourteen listings on the NEOCP today.

New MPECs  on 1 April '18

Minor Planet Electronic Circulars

As of last check at 2359 UTC, there has been one MPEC posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


<< DOU on 1 Apr. '18 >>  MPEC 2018-G01 - "12:01 UT" - Daily Orbit Update

Observers  on 1 April '18

Thirteen observers appear in today's MPEC.

CodeObserver / observatory
7058program code 8 via Apache Point Obs. in New Mexico, 1 in MPEC 2018-G01 -- 2016 VH3
251Arecibo in Puerto Rico, 7 in radar -- 2017 VR12, 2017 QL33, 509352, 505657, 418849, 3752, 1981
H21Astronomical Research Obs. Westfield in Illinois, 2 in MPEC 2018-G01 -- 2018 CE2, 2018 BY2
T05ATLAS Haleakala in Hawaii, 1 in MPEC 2018-G01 -- 11066
T08ATLAS Mauna Loa in Hawaii, 1 in MPEC 2018-G01 -- 25916
069Baldone Obs. in Latvia, 1 in MPEC 2018-G01 -- 164121
I114Joseph Masiero in southern California via Gemini South Obs. in Chile, 1 in MPEC 2018-G01 -- 2018 EB
253Goldstone DSS-14 70m antenna in southern California, 8 in radar -- 2017 VR12, 2017 QL33, 511684, 509352, 505657, 162882, 3752, 1981
Z43Landehen Obs., 1 in MPEC 2018-G01 -- 2018 FB
K22Les Barres Obs. in France, 1 in MPEC 2018-G01 -- 1627
204Schiaparelli Obs. in Italy, 14 in MPEC 2018-G01 -- 2018 DX3, 2018 DJ, 2018 DH1, 2018 DC, 2018 CZ2, 2018 CP14, 2018 CO2, 2018 BA7, 2017 VR12, 2015 RL82, 2014 QP266, 2007 LU19, 503861, 496869
W34Squirrel Valley Obs. in North Carolina, 2 in MPEC 2018-G01 -- 503861, 141484
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 4 in MPEC 2018-G01 -- 2018 FE3, 2018 FA4, 2018 EL4, 2018 AZ
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 1 April '18

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2359 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 FA4NEODyS2000209129.25e-08-7.35-7.490NEODyS: "Based on 34 optical observations (of which 0 are rejected as outliers) from 2018-03-18.365 to 2018-03-30.430."
JPL Sentry16242091-209115.778e-08-7.56-7.560JPL: Computed at 07:27 today Pacific time based on 34 observations spanning 12.065 days (2018-Mar-18.36412 to 2018-Mar-30.428877). Diameter approximately 0.028 km. from weighted mean H=25.43.
2018 FE3NEODyS20002090-211833.59e-06-6.95-7.01n/aNEODyS: "Based on 59 optical observations (of which 3 are rejected as outliers) from 2018-03-21.272 to 2018-03-30.405."
JPL Sentry16242118-211811.029e-05-6.50-6.500JPL: Computed at 07:37 today Pacific time based on 57 observations spanning 9.1330 days (2018-Mar-21.27141 to 2018-Mar-30.404422). Diameter approximately 0.012 km. from weighted mean H=27.18.
2018 EL4NEODyS20002101-211035.48e-07-6.78-6.880NEODyS: "Based on 68 optical observations (of which 0 are rejected as outliers) from 2018-03-14.211 to 2018-03-30.393."
JPL Sentry16242110-211027.399e-07-6.65-6.750JPL: Computed at 07:35 today Pacific time based on 68 observations spanning 16.182 days (2018-Mar-14.20994 to 2018-Mar-30.392206). Diameter approximately 0.032 km. from weighted mean H=25.14.

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 1 April '18

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

2122Generated Traffic Report
2000Noted that NEODyS has updated its 2018 EL4 risk assessment - see above
Noted that NEODyS has updated its 2018 FA4 risk assessment - see above
Noted that NEODyS has updated its 2018 FE3 risk assessment - see above
1624Noted that JPL Sentry has updated its 2018 EL4 risk assessment - see above
Noted that JPL Sentry has updated its 2018 FA4 risk assessment - see above
Noted that JPL Sentry has updated its 2018 FE3 risk assessment - see above
Grabbed MPEC 2018-G01 - Daily Orbit Update - see above
Noted Radar Astrometry database update - see above
0703Noted Radar Astrometry database update - see above
0430Noted Radar Astrometry database update - see above