Contents  on 1 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 1 February '18

Seven objects reported inside ten LD

There are seven asteroids known to be less than ten lunar distances (LD) from our home world today. Nearest are 2018 BQ6, which is outbound from 4.67 to 6.37 LD, and 2018 AH12, inbound from 6.67 to 6.05 LD, while risk-listed intruder 2018 BC slips away from 6.09 to 6.56 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
0.73 LD Jan. 19 2018 BC 4 m  6.09 to 6.56 LD Dec. 30 - Feb. 9 intruder, NHATS target, risk
3.07 LD Jan. 23 2018 BJ6 7 m  7.32 to 8.06 LD Jan. 12 - Feb. 4 NHATS target
3.40 LD Jan. 30 2018 BE6 44 m  7.08 to 10.59 LD Jan. 27 - today exits ten LD
3.60 LD Jan. 30 2018 BQ6 12 m  4.67 to 6.37 LD Jan. 26 - Feb. 3
5.31 LD Feb. 4 2018 AH12 14 m  6.05 from 6.67 LD Jan. 28 - Feb. 12 NHATS target
6.7   LD Jan. 15* 2018 AV2 6 m  7.1 to 7.1 LD Nov. 10 - March 2 EPU +/- 9 mins.*, NHATS target, natural?
9.27 LD Jan. 27 2018 BQ 26 m  9.85 to 10.13 LD Jan. 22 - today NHATS target, exits ten LD

This report was generated at 1740 UTC with astrometry in today's DOU MPEC for departed 2018 BU1.

Approaching Traffic - sorted by 10-LD bubble entry date
Earth passage I D ~Size Distance today  Inside ten LD Notes
3.7   LD Feb. 24* 2017 DR109 10 m  38.4 from 40.3 LD Feb. 18 - March 1 EPU +/- 30 mins.*, NHATS target
3.76 LD March 7 2017 VR12 267 m  45.69 from 46.99 LD Feb. 28 - March 13 radar/NHATS target
6.9   LD March 10* 2015 DK200 26 m  72.2 from 74.6 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. See also current sky chart and object details (alt-details), ephemerides, and today's timeline.

NEOCP Activity  on 1 February '18

The MPC's NEO Confirmation Page has 31 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 31 objects listed. Of these, five were "one nighters." So far The Tracking News has counted a total of 32 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 1 February '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 1 Feb. '18 >>  MPEC 2018-C01 - "13:15 UT" - Daily Orbit Update

Observers  on 1 February '18

Five observers appear in today's MPEC.

CodeObserver / observatory
T05ATLAS Haleakala in Hawaii, 1 in MPEC 2018-C01 -- 1980
T08ATLAS Mauna Loa in Hawaii, 1 in MPEC 2018-C01 -- 2018 AE2
160Castelmartini Obs. in Italy, 8 in MPEC 2018-C01 -- 2018 BU1, 68278, 385580, 333888, 302311, 153349, 8567, 7977
Z80Northolt Branch Obs. in England, 2 in MPEC 2018-C01 -- 475967, 154347
F51Pan-STARRS 1 (PS1) in Hawaii, 5 in MPEC 2018-C01 -- 496818, 370061, 194126, 154991, 136849
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 1 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 BP6NEODyS17002070-207624.96e-08-7.12-7.170NEODyS: "Based on 40 optical observations (of which 3 are rejected as outliers) from 2018-01-27.354 to 2018-01-30.119."
2018 BCNEODyS17002083-2113266.64e-05-6.76-7.220NEODyS: "Based on 59 optical observations (of which 1 are rejected as outliers) from 2018-01-17.211 to 2018-01-20.504."
2011 CF66JPL Sentry19022018-21178351.42283399e-05-6.00-7.220JPL: 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 1 February '18

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

1902Noted that JPL Sentry has updated its 2011 CF66 risk assessment - see above
1740Generated Traffic Report
1700Noted that NEODyS has updated its 2018 BC risk assessment - see above
Noted that NEODyS has posted 2018 BP6 as an impact risk - see above
Grabbed MPEC 2018-C01 - Daily Orbit Update - see above