Contents on 6 October '17
- Traffic Report -- four objects
- IAU Minor Planet Center
- Observers -- ten observers
- Impact Risk Monitoring -- three objects
Asteroid/Comet Connection (A/CC) Resources:
- Consolidated Risk Tables - the CRT page
Of 824 risk-listed objects, 51 have had news in the last 31 days. Updated at 1830 UTC on 6 Oct.
- Ephemerides for risk-listed objects & close passers
- News archive (old) & news image catalog (discontinued)
- Object Links - mainly for radar targets & close passers (mostly discontinued)
- Observing Campaigns (old)
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 6 October '17
Four objects reported inside ten LD
Today four visitors are reported within ten lunar distances (LD) of our home world. Nearest is new discovery 2017 TB, which is inside Earth's SOI (sphere of gravitational influence), moving away from 1.16 to 1.94 LD. And newly announced 2017 TA comes its closest to Earth this time around, reaching 2.66 LD at 2131 UTC.
|Earth passage||I D||~Size||Distance Today||Notes|
|0.13 LD Oct. 12||2012 TC4||15 m||7.78 from 9.26 LD||intruder, radar/NHATS target, risk|
|0.23 LD Oct. 2||2017 SX17||8 m||5.42 to 6.93 LD||intruder|
|1.14 LD yesterday||2017 TB||5 m||1.16 to 1.94 LD||NEW, inside Earth SOI - MPEC|
|2.66 LD today||2017 TA||37 m||2.66 LD||NEW, Earth closest at 2131 UTC - MPEC|
|Approaching (sorted by 10-LD bubble entry date)|
|8.94 LD Oct. 11||2017 SB20||36 m||< 10 LD Oct. 8|
|8.5 LD Oct. 13||2005 TE49||15 m||< 10 LD Oct. 11, uncertainty +/- 10.1167 hours, NHATS target|
|5.77 LD Oct. 22||171576 1999 VP11||645 m||< 10 LD Oct. 20|
|8.66 LD Nov. 17||444584 2006 UK||309 m||< 10 LD Nov. 16|
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 6 October '17
The MPC's NEO Confirmation Page has 61 listings
When last checked at 2323 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 61 objects listed. Of these, thirteen were "one nighters." So far The Tracking News has counted a total of 96 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 6 October '17
Minor Planet Electronic Circulars
As of last check at 2323 UTC, there have been three MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.
- MPEC 2017-T17 time-stamped "12:15 UT" - Daily Orbit Update - see below
- MPEC 2017-T18 time-stamped "16:18 UT" - 2017 TA - see below
- MPEC 2017-T19 time-stamped "16:22 UT" - 2017 TB
MPEC 2017-T19 - "16:22 UT" - 2017 TB
- K17T00B 2017 TB (risk listed, Earth MOID=0.3 LD, H=29.1 ~5m, close passer) was picked up at 0804 UT on 3 Oct. by the Mt. Lemmon Survey (MLS), observing it at Oct. 3.34p4 and 3.44p4. This detection was confirmed by Magdalena Ridge Obs. (MRO) (Oct. 3.36-38p4) and Tenagra II Obs. (Oct. 4.26-27p3 & 5.48-49p15).
MPEC 2017-T18 - "16:18 UT" - 2017 TA
- K17T00A 2017 TA (Earth MOID=0.2 LD, H=24.8 ~37m) was picked up at 0527 UT on 3 Oct. by MLS, observing it at Oct. 3.23-24p3 and 3.31p3. This detection was confirmed by MRO (Oct. 3.27-29p4 & 4.08-11p4), Tenagra II Obs. (Oct. 4.14-15p3, 5.13p3 & 6.11p3), Castelmartini Obs. (Oct. 4.75-76p3), Great Shefford Obs. (Oct. 5.78-79p4 & 5.95-96p4), San Marcello Pistoiese Obs. (Oct. 5.84p3), and Northolt Branch Obs. (Oct. 5.86-87p4).
- Observations of risk-listed objects
- K17S20F 2017 SF20 (small asteroid, arc=3 days, H=28.3 ~7m, close passer) from Pan-STARRS 1 (PS1) (Sept. 29.51-53p2)
- K17R02V 2017 RV2 (small asteroid, arc=13 days, H=26.2 ~19m, close passer) from PS1 (Sept. 17.49-51p2)
- Observation campaigns (NHATS targets, radar support)
- 68950 68950 2002 QF15 (radar) from WISE (Sept. 25.93p1, 26.06p1, 26.19p1, 26.39p1, 26.52p1, 26.72p1, 26.98p1 & 27.11p2)
- 65679 65679 1989 UQ (NHATS) from Ondrejov Obs. (Sept. 20.90-94p2, 20.98p1, 21.02-06p2, 21.10p1, 21.15p1, 28.08-16p3, 29.92p1, 29.98-02p2, 30.07p1, 30.12p1, Oct. 1.06p1, 1.10-14p2, 1.88-92p2, 1.96-03p3 & 2.07-11p2)
-- NHATS target table & ephemerides -- Planetary radar schedules: Arecibo & Goldstone
- Observations of small (H>22.0) & smallish (21.7<H<=22.0) asteroids
- K17S14T 2017 ST14 (Q=4.220 AU, arc=14 days, H=23.4 ~71m) from Tenagra II Obs. (Oct. 5.13p3)
- K04R84E 2004 RE84 (arc=2 opp, H=21.9 ~141m) from Castelmartini Obs. (Sept. 21.94-95p3)
- Observations of other objects
- K17P26J 2017 PJ26 (arc=52 days, H=19.3 ~467m) from Castelmartini Obs. (Sept. 21.95p3)
- K17O68P 2017 OP68 (arc=70 days, H=21.0 ~214m) from Castelmartini Obs. (Sept. 21.97p3)
- K17N06U 2017 NU6 (arc=69 days, H=19.5 ~426m) from WISE (Sept. 22.13p1, 22.19p1, 22.26p1, 22.39p1 & 22.46p1)
- K14Y15C 2014 YC15 (arc=2 opp, H=18.7 ~616m) from Castelmartini Obs. (Sept. 21.98p3)
- K14SX9R 2014 SR339 (arc=3 opp, H=18.5 ~676m) from WISE (Sept. 20.68p1, 20.81p1, 20.88p1, 21.27p1 & 21.40p1)
- f1201 411201 2010 LJ14 from Castelmartini Obs. (Sept. 21.99p3)
- X3888 333888 1998 ST4 from Castelmartini Obs. (Sept. 21.97-98p3)
- E3624 143624 2003 HM16 from Castelmartini Obs. (Sept. 22.00p3)
- E2464 142464 2002 TC9 from Castelmartini Obs. (Sept. 21.96-97p3)
- 11500 11500 Tomaiyowit (1989 UR) from Castelmartini Obs. (Sept. 21.96p3)
- 03122 3122 Florence (1981 ET3) from WISE (Sept. 24.57p1, 24.70p1, 24.83p1, 24.96p1, 25.22p1, 25.35p1, 25.88p1, 26.01p1, 26.14p2, 26.27p1 & 26.40p1)
Observers on 6 October '17
Ten observers appear in today's MPECs.
|Code||Observer / observatory|
|160||Castelmartini Obs. in Italy, 10 in MPECs 2017-T17 & 2017-T18 -- 2017 TA, 2017 PJ26, 2017 OP68, 2014 YC15, 2004 RE84, 411201, 333888, 143624, 142464, 11500|
|J95||Great Shefford Obs. in England, 1 in MPEC 2017-T18 -- 2017 TA|
|H01||Magdalena Ridge Obs. (MRO) in New Mexico, 2 in MPECs 2017-T18 & 2017-T19 -- 2017 TB, 2017 TA|
|G96||Mt. Lemmon Survey (MLS) in Arizona, 2 in MPECs 2017-T18 & 2017-T19 -- 2017 TB, 2017 TA|
|Z80||Northolt Branch Obs. in England, 1 in MPEC 2017-T18 -- 2017 TA|
|557||Ondrejov Obs. in the Czech Republic, 1 in MPEC 2017-T17 -- 65679|
|F51||Pan-STARRS 1 (PS1) in Hawaii, 2 in MPEC 2017-T17 -- 2017 SF20, 2017 RV2|
|104||San Marcello Pistoiese Obs. in Italy, 1 in MPEC 2017-T18 -- 2017 TA|
|926||Tenagra II Obs. in Arizona, 3 in MPECs 2017-T17, 2017-T18 & 2017-T19 -- 2017 TB, 2017 TA, 2017 ST14|
|C51||WISE in Earth polar orbit, 4 in MPEC 2017-T17 -- 2017 NU6, 2014 SR339, 68950, 3122|
|For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.|
Impact Risk Monitoring on 6 October '17
Notes for Today's Latest Risk Assessments
|2017 TB||JPL Sentry||1830||2054-2117||54||5.06149892e-05||-6.61||-7.22||0||JPL: Computed at 11:20 today Pacific time based on 30 observations spanning 2.1484 days (2017-Oct-03.33674 to 2017-Oct-05.48518). Diameter approximately 0.005 km. from weighted mean H=29.13.|
|2017 SF20||NEODyS||1600||2034-2036||3||4.27e-04||-4.53||-4.53||0||NEODyS: "Based on 26 optical observations (of which 2 are rejected as outliers) from 2017-09-28.368 to 2017-10-01.356."|
|JPL Sentry||1535||2034-2034||1||2.674e-04||-4.74||-4.74||0||JPL: Computed at 07:51 today Pacific time based on 26 observations spanning 2.9882 days (2017-Sep-28.36701 to 2017-Oct-01.35517). Diameter approximately 0.007 km. from weighted mean H=28.32.|
|2017 RV2||NEODyS||1600||2071-2117||39||4.95e-05||-5.27||-5.78||0||NEODyS: "Based on 131 optical observations (of which 10 are rejected as outliers) from 2017-09-14.436 to 2017-09-27.493."|
|JPL Sentry||1535||2071-2117||41||0.000105661304||-4.94||-5.72||0||JPL: Computed at 08:02 today Pacific time based on 131 observations spanning 13.057 days (2017-Sep-14.43497 to 2017-Sep-27.49213). Diameter approximately 0.019 km. from weighted mean H=26.21.|
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 6 October '17
Times are UTC for when items were noted or added by The Tracking News.
|1830||Noted that JPL Sentry has posted 2017 TB as an impact risk - see above|
|1820||Generated Traffic Report|
|1700||Grabbed MPEC 2017-T18 - 2017 TA - see above|
Grabbed MPEC 2017-T19 - 2017 TB - see above
|1600||Noted that NEODyS has updated its 2017 RV2 risk assessment - see above|
Noted that NEODyS has updated its 2017 SF20 risk assessment - see above
|1535||Noted that JPL Sentry has updated its 2017 RV2 risk assessment - see above|
Noted that JPL Sentry has updated its 2017 SF20 risk assessment - see above
Grabbed MPEC 2017-T17 - Daily Orbit Update - see above