Contents  on 27 June '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 27 June '18

Two objects reported inside ten LD

There are two transient natural objects reported within ten lunar distances (LD) of Earth today. Nearest is 2018 MX4, which comes its closest on this passage -- 5.52 LD at 1821 UTC.

Neighborhood Traffic - sorted by Earth passage distance
Earth passage I D ~Size Distance today  Inside ten LD Notes
5.52 LD today 2018 MX4 14 m  5.52 LD June 23 - July 2 Earth closest at 1821 UTC - DOU
6.01 LD June 29 2018 LR3 19 m  6.20 from 6.46 LD June 20 - July 8 NHATS target, risk
Approaching
2.8   LD July 4* 2018 MB7 60 m  16.8 from 19.4 LD June 30 - July 8 Earth passage uncertainty +/- 40 mins.*

This report was generated at 2112 UTC with follow-up in today's DOU MPEC for passing 2018 MX4 and departed objects 2018 MG7 and risk-listed 2018 JG1, as well as the recovery of 441987 2010 NY65, which we are belatedly adding to this reporting. It left our ten-LD traffic reporting "bubble" yesterday after flying by at 7.28 LD on the 24th. It also visited the bubble last June and will come inside again this time next year.


<< Reading:  The European Southern Observatory has a news item explaining that an international collaboration of astronomers has concluded that 1I/`Oumuamua (2017 U1) (links) "is moving faster than predicted," which may be explained by unobserved but comet-like venting of "coarse dust grains." NASA/JPL also has a report.
        The Okinawa Institute of Science and Technology has an interesting explanation today about how the rays of impact craters are formed.



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 27 June '18

The MPC's NEO Confirmation Page has 23 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 23 objects listed. Of these, ten were "one nighters." So far The Tracking News has counted a total of 24 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 27 June '18

Minor Planet Electronic Circulars

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


<< DOU on 27 June '18 >>  MPEC 2018-M102 - "12:03 UT" - Daily Orbit Update


MPEC 2018-M101 - "00:47 UT" - 2018 MM8

Observers  on 27 June '18

Fifteen observers appear in today's MPECs.

CodeObserver / observatory
T05ATLAS Haleakala in Hawaii, 3 in MPEC 2018-M102 -- 85989, 66391, 1866
T08ATLAS Mauna Loa in Hawaii, 13 in MPEC 2018-M102 -- 2011 GA62, 2009 OG, 65706, 518469, 408752, 18882, 18109, 17511, 7889, 6456, 5604, 1685, 1036
B96Brixiis Obs. in Belgium, 1 in MPEC 2018-M101 -- 2018 MM8
160Castelmartini Obs. in Italy, 4 in MPECs 2018-M101 & 2018-M102 -- 2018 MM8, 2017 YE5, 2011 GA62, 455550
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 4 in MPEC 2018-M102 -- 2018 LE3, 2018 LD16, 2018 KB4, 2017 UX5
J95Great Shefford Obs. in England, 3 in MPECs 2018-M101 & 2018-M102 -- 2018 MX4, 2018 MM8, 2018 MG7
P93JAXA Space Tracking & Communications Center in Japan, 1 in MPEC 2018-M101 -- 2018 MM8
Z43Landehen Obs., 3 in MPEC 2018-M102 -- 2018 MG7, 2017 YE5, 68950
K38M57 Obs. in Italy, 2 in MPEC 2018-M102 -- 2018 MM8, 283729
G96Mt. Lemmon Survey in Arizona, 1 in MPEC 2018-M101 -- 2018 MM8
Z80Northolt Branch Obs. in England, 3 in MPEC 2018-M102 -- 2018 MG7, 2017 YE5, 2011 GA62
I41Palomar Transient Factory in southern California, 1 in MPEC 2018-M102 -- 441987
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2018-M102 -- 174050
I52Steward Obs. Mt. Lemmon Station in Arizona, 1 in MPEC 2018-M101 -- 2018 MM8
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 2 in MPEC 2018-M102 -- 2018 MX4, 2018 JG1
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 27 June '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 MH7NEODyS1430211617.89e-08-8.20-8.20NEODyS: "Based on 11 optical observations (of which 0 are rejected as outliers) from 2018-06-23.553 to 2018-06-25.401."
2018 MD7NEODyS14302042-2116199.68e-08-6.29-6.430NEODyS: "Based on 21 optical observations (of which 0 are rejected as outliers) from 2018-06-21.383 to 2018-06-26.432."
2018 MC7NEODyS14302049-21161339.71e-05-4.61-4.880NEODyS: "Based on 25 optical observations (of which 0 are rejected as outliers) from 2018-06-21.395 to 2018-06-26.391."
2018 MW6NEODyS1509R E M O V E D-
2018 MX4NEODyS1509R E M O V E D-
2018 LV3NEODyS1430206119.19e-08-7.74-7.740NEODyS: "Based on 38 optical observations (of which 0 are rejected as outliers) from 2018-06-11.383 to 2018-06-14.182."
2018 LR3NEODyS14302074-2118142.41e-06-6.68-6.93n/aNEODyS: "Based on 51 optical observations (of which 0 are rejected as outliers) from 2018-06-10.326 to 2018-06-25.247."
2018 LMNEODyS14302112-211633.64e-06-6.06-6.250NEODyS: "Based on 90 optical observations (of which 0 are rejected as outliers) from 2018-06-04.255 to 2018-06-25.282."
2018 JG1NEODyS1535206813.5e-11-10.31-10.310NEODyS: "Based on 86 optical observations (of which 0 are rejected as outliers) from 2018-05-08.180 to 2018-06-25.606."

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 27 June '18

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

2112Generated Traffic Report
1535Noted that NEODyS has updated its 2018 JG1 risk assessment - see above
1509Noted that NEODyS has posted 2018 MH7 as an impact risk - see above
Noted that NEODyS has removed 2018 MW6 as an impact risk - see above
Noted that NEODyS has removed 2018 MX4 as an impact risk - see above
1430Noted that NEODyS has updated its 2018 LM risk assessment - see above
Noted that NEODyS has updated its 2018 LR3 risk assessment - see above
Noted that NEODyS has updated its 2018 LV3 risk assessment - see above
Noted that NEODyS has updated its 2018 MC7 risk assessment - see above
Noted that NEODyS has updated its 2018 MD7 risk assessment - see above
Grabbed MPEC 2018-M102 - Daily Orbit Update - see above
0055Grabbed MPEC 2018-M101 - 2018 MM8 - see above