Contents  on 14 February '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 14 February '18

Eight objects reported inside ten LD

Eight transient natural objects are known to be less than ten lunar distances (LD) from Earth today. Nearest is intruder 2018 CD3, which slides into our planet's sphere of gravitational influence (SOI), coming in from 3.23 to 1.68 LD. 2018 CU2 also enters the SOI, moving in from 3.23 to 2.26 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
0.18 LD Feb. 9 2018 CB 22 m  5.96 to 7.41 LD Feb. 3 - 16 intruder, NHATS target
0.92 LD tomorrow 2018 CD3 7 m  1.68 from 3.23 LD Feb. 9 - 21 intruder, NHATS target, enters Earth SOI - DOU
2.05 LD Feb. 12 2018 CH2 8 m  3.27 to 5.02 LD Feb. 7 - 17 DOU
2.23 LD tomorrow 2018 CU2 9 m  2.26 from 3.23 LD Feb. 10 - 20 enters Earth SOI - DOU
5.65 LD Feb. 11 2018 CX 31 m  7.71 to 9.57 LD Feb. 8 - 15
6.66 LD Jan. 15 2018 AV2 6 m  7.99 to 8.08 LD Nov. 10 - March 2 NHATS target, natural?
6.75 LD yesterday 2018 CR3 26 m  6.75 to 8.22 LD Feb. 12 - 15 NEW - MPEC, DOU
9.63 LD tomorrow 2018 CB1 27 m  9.64 from 10.10 LD today - Feb. 16 enters ten LD - DOU

This report was generated at 1808 UTC with the discovery of 2018 CR3 (MPEC, DOU) announced late yesterday and now in the active traffic table above. Today's DOU MPEC has first follow-up for approaching 2018 CP2, inbound objects 2018 CU2 and intruder 2018 CD3, and outbound objects 2018 CR3 and 2018 CH2, along with continuing follow-up for inbound 2018 CB1 and departed objects 2018 BQ and risk-listed intruder 2018 BN6.

Approaching Traffic - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
6.08 LD Feb. 19 2018 CP2 47 m  13.52 from 15.82 LD Feb. 16 - 22 DOU
3.7   LD Feb. 24* 2017 DR109 10 m  15.7 from 17.4 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
9.26 LD Feb. 20 2018 CJ 63 m  20.55 from 23.72 LD Feb. 19 - 21
3.76 LD March 7 2017 VR12 265 m  28.53 from 29.87 LD Feb. 28 - March 13 radar/NHATS target
6.9   LD March 10* 2015 DK200 26 m  43.9 from 45.9 LD March 6 - 14 EPU +/- 23.45 hours*, NHATS target
* EPU = Earth passage uncertainty

Fat DOU update:  This past Saturday we reported that that day's Daily Orbit Update (DOU) MPEC "also posts astrometry from 2012 through this January that we are still processing for some 90 close passers." To begin with, a DOU in the last couple weeks has typically reported positions on the celestial globe (aka astrometry, observations, follow-up) for around 27 to 149 near-Earth asteroids. Today, for example, there are 64 objects in the DOU.
        We should note here that in our Earth's Busy Neighborhood traffic reporting, we unconventionally use the the term "follow-up" to describe active new observation of objects that are currently or were recently nearby, or are approaching, and we use "astrometry" for older observations that may be new but delayed, or may be restated data, corrected due to timing issues or other problems. We usually don't know, and, if we do know, there's rarely need to point out restated data.
        Anyway, to continue... Last Friday's DOU had observations for a surprising 349 objects, including astrometry for seven close passers, all but one numbered. And then Saturday's DOU carried observations for a perhaps unprecedented 788 objects. Ninety of those, none of them numbered, have flown within ten LD of Earth since we started neighborhood traffic reporting in January 2007, meriting our special attention here. They had astrometry in the DOU anywhere from 2012 through January of this year. It took twelve hours for us to run a batch of just 77 of these objects through NASA/JPL Horizons via telnet. But the results were interesting. Restated improved observations were likely included but 31 of the 90 objects had their observing spans extended in addition to one recovery, one pre-discovery, and one pre-recovery. In other words, a lot of this was new, not revised. And, by the way, seven of these objects were risk listed, five had flown through the Earth-Moon system (what we call "intruders" in reporting here), and one had missed our little system but "buzzed" the Moon at less than one lunar distance. And that buzzer and three other objects going back to 2015 actually had their first follow-up published on Saturday.
        Whatever the sources and reason for this large data dump, clearly some valuable new work was published.

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 14 February '18

The MPC's NEO Confirmation Page has 72 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 72 objects listed. Of these, 28 were "one nighters." So far The Tracking News has counted a total of 75 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 14 February '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.

MPEC 2018-C105 - "22:40 UT" - 2017 CX33

<< DOU on 14 Feb. '18 >>  MPEC 2018-C104 - "13:06 UT" - Daily Orbit Update

Observers  on 14 February '18

A total of 20 observers appear in today's MPECs.

CodeObserver / observatory
C97Al-Fulaij Obs., 7 in MPEC 2018-C104 -- 505657, 311554, 12711, 7977, 6053, 3122, 1980
T05ATLAS Haleakala in Hawaii, 4 in MPEC 2018-C104 -- 248926, 154652, 6050, 1980
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 5 in MPEC 2018-C104 -- 2018 BC6, 2018 AC12, 2017 YP5, 2017 YA2, 2017 SL17
K87Dettelbach Vineyard Obs. in Germany, 1 in MPEC 2018-C104 -- 2018 CQ3
G37Discovery Channel Telescope in Arizona, 1 in MPEC 2018-C105 -- 2017 CX33
K83Forti Obs., 1 in MPEC 2018-C104 -- 311554
J95Great Shefford Obs. in England, 8 in MPEC 2018-C104 -- 2018 CY2, 2018 CU2, 2018 CS2, 2018 CR3, 2018 CR2, 2018 CQ3, 2018 CD3, 2018 CC1
A17Guidestar Obs. in Germany, 7 in MPEC 2018-C104 -- 2018 CU1, 2018 CP2, 2018 CC1, 2018 BJ7, 2018 AE2, 2017 YT7, 2017 XH62
P93JAXA Space Tracking & Communications Center in Japan, 1 in MPEC 2018-C104 -- 2018 CY2
K38M57 Obs. in Italy, 1 in MPEC 2018-C104 -- 505657
474Mt. John Obs. in New Zealand, 9 in MPEC 2018-C104 -- 2018 CH2, 2018 CB1, 2018 CA2, 2018 BZ2, 2018 BQ, 2018 BK5, 2018 AH13, 2017 UY4, 2017 UE45
G96Mt. Lemmon Survey in Arizona, 1 in MPEC 2018-C104 -- 7977
K74Muensterschwarzach Obs. in Germany, 5 in MPEC 2018-C104 -- 2017 XB2, 333888, 25916, 3122, 1980
628Mulheim-Ruhr Obs. in Germany, 1 in MPEC 2018-C104 -- 40267
408Nyukasa Obs. in Japan, 1 in MPEC 2018-C104 -- 2018 CY2
G34Oberfrauendorf Obs. in Germany, 2 in MPEC 2018-C104 -- 505657, 6053
J43Oukaimeden Obs. in Morocco, 2 in MPEC 2018-C104 -- 2018 BT6, 508861
I41Palomar Transient Factory (PTF) in southern California, 15 in MPEC 2018-C104 -- 2018 CP2, 2018 BT6, 2015 NJ3, 2007 LU19, 2005 BS27, 2004 CK39, 88213, 508871, 508861, 38091, 185853, 162011, 137925, 8567, 7977
F51Pan-STARRS 1 (PS1) in Hawaii, 8 in MPECs 2018-C104 & 2018-C105 -- 2017 XV2, 2017 DD38, 2017 CX33, 446791, 424482, 219527, 152563, 6053
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 3 in MPEC 2018-C104 -- 2018 BN6, 2018 AT, 2018 AB12
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 14 February '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.





Notes for Today's Latest Risk Assessments
2018 BN6JPL Sentry16142077-2117221.89797e-05-5.81-6.010JPL: Computed at 08:12 today Pacific time based on 48 observations spanning 17.199 days (2018-Jan-27.19371 to 2018-Feb-13.392345). Diameter approximately 0.015 km. from weighted mean H=26.78.

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 14 February '18

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

2301Grabbed MPEC 2018-C105 - 2017 CX33 - see above
1808Generated Traffic Report
1614Noted that JPL Sentry has updated its 2018 BN6 risk assessment - see above
Grabbed MPEC 2018-C104 - Daily Orbit Update - see above