Contents  on 18 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 18 February '18

Five objects reported inside ten LD

There are five planetesimals known to be within ten lunar distances (LD) of our home world today. Nearest is intruder 2018 CD3, which is outbound from 3.76 to 5.40 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
0.92 LD Feb. 15 2018 CD3 6 m  3.76 to 5.40 LD Feb. 9 - 21 intruder, NHATS target
2.23 LD Feb. 15 2018 CU2 9 m  6.02 to 7.90 LD Feb. 10 - 20
3.7   LD Feb. 24* 2017 DR109 10 m  9.4 from 10.9 LD today - March 1 EPU +/- 30 mins.*, NHATS target, enters ten LD
6.08 LD tomorrow 2018 CP2 48 m  6.39 from 7.56 LD Feb. 16 - 22
6.66 LD Jan. 15 2018 AV2 6 m  8.39 to 8.50 LD Nov. 10 - March 2 NHATS target, natural?

This report was generated at 1724 UTC with follow-up in today's DOU MPEC for 450894 2008 BT18, which isn't coming inside our ten-LD traffic reporting sphere during this period of observation.

Approaching Traffic - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
9.26 LD Feb. 20 2018 CJ 64 m  10.30 from 12.21 LD tomorrow - Feb. 21
5.17 LD Feb. 24 2018 CE14 25 m  13.95 from 16.11 LD Feb. 20 - 28 NHATS target
3.76 LD March 7 2017 VR12 273 m  23.13 from 24.48 LD Feb. 28 - March 13 radar/NHATS target
6.9   LD March 10* 2015 DK200 26 m  36.0 from 37.9 LD March 6 - 14 EPU +/- 23.45 hours*, 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.

NEOCP Activity  on 18 February '18

The MPC's NEO Confirmation Page has 31 listings

When last checked at 2330 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 31 objects listed. Of these, eleven were "one nighters." So far The Tracking News has counted a total of 39 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 18 February '18

Minor Planet Electronic Circulars

As of last check at 2330 UTC, there has been one MPEC posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.

<< DOU on 18 Feb. '18 >>  MPEC 2018-D21 - "13:04 UT" - Daily Orbit Update

Observers  on 18 February '18

Eleven observers appear in today's MPEC.

CodeObserver / observatory
C97Al-Fulaij Obs., 4 in MPEC 2018-D21 -- 505657, 311554, 6053, 3122
703Catalina Sky Survey (CSS) in Arizona, 3 in MPEC 2018-D21 -- 482796, 259802, 252373
J95Great Shefford Obs. in England, 1 in MPEC 2018-D21 -- 2018 CT3
G96Mt. Lemmon Survey (MLS) in Arizona, 8 in MPEC 2018-D21 -- 2018 CZ2, 2018 CP3, 2018 BO3, 2017 SL33, 2013 QH10, 450894, 38091, 142348
644NEAT's Mt. Palomar telescope in southern California, 2 in MPEC 2018-D21 -- 7977, 6050
608NEAT's USAF Haleakala telescope in Hawaii, 3 in MPEC 2018-D21 -- 7977, 6050, 1864
Z80Northolt Branch Obs. in England, 3 in MPEC 2018-D21 -- 475967, 162882, 137925
F51Pan-STARRS 1 (PS1) in Hawaii, 2 in MPEC 2018-D21 -- 68278, 7977
691Spacewatch 0.9m telescope in Arizona, 1 in MPEC 2018-D21 -- 251346
I52Steward Obs. Mt. Lemmon Station in Arizona, 6 in MPEC 2018-D21 -- 2018 CZ, 2018 CX1, 2018 CS2, 2018 CP3, 2018 CG2, 2018 CE2
Z52The Studios Obs., 1 in MPEC 2018-D21 -- 137062
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 18 February '18

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2330 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
2011 CF66JPL Sentry20402019-21178321.42031109e-05-6.02-7.220JPL: Computed at 03:11 April 7th of 2017 Pacific time based on 11 observations spanning .17761 days (2011-Feb-13.33976 to 2011-Feb-13.51737). Diameter approximately 0.009 km. from weighted mean H=27.83.

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 18 February '18

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

2040Noted that JPL Sentry has updated its 2011 CF66 risk assessment - see above
1724Generated Traffic Report
1632Grabbed MPEC 2018-D21 - Daily Orbit Update - see above