Contents  on 21 August '17

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 21 August '17

Three objects reported inside ten LD

Today three asteroids are known to be less than ten lunar distances (LD) from our home world. Intruder 2017 QN2 is the closest by far, within one LD of both the Earth and Moon before ending the day out at 3.76 LD from Earth.

Earth passage I D ~Size Distance Today  Notes
0.56 LD yesterday2017 QN2 9 m  0.64 to 3.76 LD intruder today, exits Earth SOI, Moon closest 0.69 LD at 0436 UTC - DOU
2.59 LD tomorrow2017 QT1 15 m  4.39 from 8.57 LD risk
5.50 LD tomorrow2017 PV25 40 m  5.59 from 6.01 LD DOU
Approaching (sorted by 10-LD bubble entry date)
9.10 LD Aug. 252017 QJ2 21 m  < 10 LD Aug. 24
5.49 LD Aug. 302017 QN1 17 m  < 10 LD Aug. 26
4.82 LD Aug. 312017 QQ1 38 m  < 10 LD Aug. 27
7.87 LD Sept. 291989 VB 389 m  < 10 LD Sept. 25
0.13 LD Oct. 122012 TC4 15 m  < 10 LD Oct. 5, intruder, radar/NHATS target, risk
8.5   LD Oct. 132005 TE49 15 m  < 10 LD Oct. 11, uncertainty +/- 10.1167 hours, NHATS target
5.77 LD Oct. 22171576 1999 VP11 645 m  < 10 LD Oct. 20

This report was generated at 1753 UTC with first follow-up for 2017 QN2 and departed 2017 QW1 in today's DOU MPEC as well as continuing follow-up for 2017 PV25 and departed radar target 2017 CS.



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 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 21 August '17

The MPC's NEO Confirmation Page has 73 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 73 objects listed. Of these, seventeen were "one nighters." So far The Tracking News has counted a total of 77 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 21 August '17

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 21 Aug. '17 >>  MPEC 2017-Q79 - "12:04 UT" - Daily Orbit Update


MPEC 2017-Q78 - "02:37 UT" - 2011 GS60

Observers  on 21 August '17

A total of 21 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 24 in MPEC 2017-Q79 -- 2017 QX1, 2017 QW1, 2017 QE2, 2017 QC2, 2017 OT18, 2017 OL1, 2017 OH7, 2017 OC, 2017 NM6, 2017 MV2, 2017 MQ8, 2017 KR34, 2017 CS, 2013 TH5, 2009 BF, 494706, 304640, 222073, 159467, 142561, 11398, 7888, 2329, 1917
T05ATLAS Haleakala in Hawaii, 6 in MPEC 2017-Q79 -- 480858, 242211, 159467, 137799, 13651, 3752
T08ATLAS Mauna Loa in Hawaii, 13 in MPEC 2017-Q79 -- 2017 OF7, 2008 MH1, 2006 KA40, 85709, 52762, 422699, 326388, 265962, 142464, 142040, 136818, 9202, 6053
160Castelmartini Obs. in Italy, 16 in MPEC 2017-Q79 -- 2017 PV25, 2014 YC15, 90075, 68348, 496018, 495848, 422699, 265962, 20460, 190166, 142561, 142040, 12538, 5143, 3288, 1980
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 13 in MPEC 2017-Q79 -- 2017 QK, 2017 PX26, 2017 PU25, 2017 PS25, 2017 PO26, 2017 PJ26, 2017 OX18, 2017 OV18, 2017 OJ19, 2017 OE20, 2017 NQ6, 2017 KS31, 2017 HW1
J27El Guijo Obs. in Spain, 3 in MPEC 2017-Q79 -- 2017 PL26, 496018, 265962
157Frasso Sabino Obs. in Italy, 3 in MPEC 2017-Q79 -- 2017 QB, 2017 PT25, 2017 OT18
A17Guidestar Obs. in Germany, 2 in MPEC 2017-Q79 -- 2017 PE, 2017 OT18
W19Kalamazoo Obs. in Michigan, 1 in MPEC 2017-Q79 -- 90075
Z43Landehen Obs., 2 in MPEC 2017-Q79 -- 190166, 2329
Z22MASTER IAC Obs. in the Canary Islands, 2 in MPEC 2017-Q79 -- 142561, 3752
K95MASTER-II Sutherland in South Africa, 1 in MPEC 2017-Q79 -- 434096
F51Pan-STARRS 1 (PS1) in Hawaii, 5 in MPEC 2017-Q79 -- 2017 OH68, 2012 FH38, 52768, 152664, 5786
W98Polonia Obs. in Chile, 1 in MPEC 2017-Q79 -- 141874
A48Povegliano Veronese Obs. in Italy, 1 in MPEC 2017-Q79 -- 2017 PL26
D29Purple Mtn. Obs. Xuyi Station in China, 3 in MPEC 2017-Q79 -- 2009 BF, 223456, 136818
L04ROASTERR-1 in Romania, 3 in MPEC 2017-Q79 -- 2017 PT25, 2017 OT18, 2014 YC15
104San Marcello Pistoiese Obs. in Italy, 1 in MPEC 2017-Q79 -- 2017 QN2
K14Sencelles Obs. in Spain, 1 in MPEC 2017-Q79 -- 2017 OT18
Z52The Studios Obs., 2 in MPEC 2017-Q79 -- 90075, 190166
T14UH/Tholen NEO Follow-Up CFH Telescope in Hawaii, 1 in MPEC 2017-Q78 -- 2011 GS60
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 21 August '17

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
2017 PL26JPL Sentry15302081-2116452.25060879e-05-3.64-4.400JPL: Computed at 08:02 today Pacific time based on 110 observations spanning 7.6017 days (2017-Aug-13.40074 to 2017-Aug-21.00247). Diameter approximately 0.120 km. from weighted mean H=22.20.

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 21 August '17

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

1753Generated Traffic Report
1530Noted that JPL Sentry has updated its 2017 PL26 risk assessment - see above
Grabbed MPEC 2017-Q79 - Daily Orbit Update - see above
0305Grabbed MPEC 2017-Q78 - 2011 GS60 - see above