Contents  on 3 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 3 April '18

Four objects reported inside ten LD

Four small Solar-System bodies are reported inside ten lunar distances (LD) of Earth today. Then nearest may be 2004 FG29, not yet recovered on this passage but calculated to be outbound from around 4.2 to 6.2 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  8.75 to 11.29 LD March 26 - today intruder, exits ten LD, risk
4.0   LD yesterday* 2004 FG29 21 m  4.2 to 6.2 LD March 30 - April 5 EPU +/- 1.03 hours*
4.88 LD March 29 2018 FB 54 m  9.18 to 10.83 LD March 25 - today exits ten LD
6.23 LD April 1 2018 EM4 30 m  6.69 to 7.32 LD March 26 - April 6 NHATS target

This report was generated at 1850 UTC with follow-up in today's DOU MPEC for departed 2018 DH1 and with radar astrometry from January for 2018 AJ.

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  10.14 from 11.17 LD tomorrow - April 5
9.24 LD April 14 2014 UR 16 m  13.77 from 14.51 LD April 10 - 18 NHATS target
6.2   LD May 8* 2016 JQ5 8 m  88.2 from 91.2 LD May 4 - 11 EPU +/- 14.00 hours*
9.65 LD May 7 1999 FN19 112 m  42.14 from 43.29 LD May 5 - 9 radar/NHATS target
6.48 LD May 9 388945 2008 TZ3 282 m  77.93 from 80.44 LD May 5 - 13
9.50 LD May 29 68347 2001 KB67 371 m  201.92 from 206.95 LD May 28 - 30 radar target
5.6   LD June 10* 2018 EJ4 181 m  88.5 from 89.8 LD June 4 - 16 EPU +/- 45 mins.*, radar/NHATS target
8.96 LD June 11 2015 DP155 162 m  56.67 from 57.36 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 3 April '18

Radar observation of four 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 1515 UTC when the database was dated 2 April

NEOCP Activity  on 3 April '18

The MPC's NEO Confirmation Page has 9 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had nine objects listed. Of these, five were "one nighters."

New MPECs  on 3 April '18

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 3 Apr. '18 >>  MPEC 2018-G16 - "12:01 UT" - Daily Orbit Update

Observers  on 3 April '18

Fourteen observers appear in today's MPEC.

CodeObserver / observatory
B37Ametlla del Valles Obs. in Spain, 2 in MPEC 2018-G16 -- 2015 XE352, 2014 QP266
251Arecibo in Puerto Rico, 4 in radar -- 2018 AJ, 2017 XT61, 509935, 438017
160Castelmartini Obs. in Italy, 10 in MPEC 2018-G16 -- 2018 DH1, 85953, 85628, 40267, 350988, 25916, 194126, 14402, 7889, 1627
703Catalina Sky Survey in Arizona, 1 in MPEC 2018-G16 -- 515767
107Cavezzo Obs. in Italy, 1 in MPEC 2018-G16 -- 172034
U699Steven M. Tilley in Louisiana via iTelescope Obs. Auberry in northern California, 1 in MPEC 2018-G16 -- 2018 BY2
246KLENOT in the Czech Republic, 1 in MPEC 2018-G16 -- 2018 DH1
D29Purple Mtn. Obs. Xuyi Station in China, 4 in MPEC 2018-G16 -- 475967, 337228, 152931, 1866
L04ROASTERR-1 in Romania, 3 in MPEC 2018-G16 -- 2018 DX3, 2018 BY2, 2015 XE352
691Spacewatch 0.9m telescope in Arizona, 5 in MPEC 2018-G16 -- 2018 FS3, 2018 FJ4, 2018 EQ4, 2017 TV4, 2017 BD29
W34Squirrel Valley Obs. in North Carolina, 2 in MPEC 2018-G16 -- 497117, 475967
W33Transit Dreams Obs., 7 in MPEC 2018-G16 -- 2018 DX3, 85953, 475967, 172034, 163243, 152931, 1866
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 1 in MPEC 2018-G16 -- 2018 FU1
C51WISE in Earth polar orbit, 4 in MPEC 2018-G16 -- 333888, 154268, 152931, 6053
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 3 April '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 FU1JPL Sentry15152059-2117191.68517505e-05-6.05-6.440JPL: Computed at 07:39 today Pacific time based on 24 observations spanning 8.9618 days (2018-Mar-18.47342 to 2018-Mar-27.43525). Diameter approximately 0.014 km. from weighted mean H=26.90.

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 3 April '18

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

1850Generated Traffic Report
1515Noted that JPL Sentry has updated its 2018 FU1 risk assessment - see above
Grabbed MPEC 2018-G16 - Daily Orbit Update - see above
Noted Radar Astrometry database update - see above