Full-scale NEA Scout solar sail deployment test.
 Credit: Emmett Given at NASA/MSFC.

The NASA/JPL NEA Scout full-scale solar sail shown deployed in a recent test in Alabama. The asteroid-chasing six-unit CubeSat spacecraft that the sail will propel is scheduled to be a secondary payload on NASA's SLS EM-1 mission that will reportedly launch in December 2019 or later. Image credit: Emmett Given at NASA/MSFC.


Contents  on 1 October '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 1 October '17

Five objects reported inside ten LD

There are five asteroids reported to be within ten lunar distances (LD) of Earth today. Nearest is intruder 2017 SX17, which enters the Earth-Moon system and passes the Moon at 0.68 LD at 2228 UTC.

Earth passage I D ~Size Distance Today  Notes
0.23 LD tomorrow2017 SX17 8 m  0.70 from 2.20 LD intruder today, Moon closest 0.68 LD at 2228 UTC - DOU
1.49 LD Sept. 272017 SA21 7 m  8.39 to 10.62 LD NEW, risk, exits ten LD - MPEC
5.38 LD Oct. 32017 SS16 16 m  7.03 from 9.79 LD DOU
7.87 LD Sept. 291989 VB 389 m  8.04 to 8.44 LD radar target
9.14 LD Sept. 302017 SH16 30 m  9.23 to 10.14 LD exits ten LD - DOU

This report was generated at 2048 UTC with the discovery of 2017 SA21 (MPEC), which leaves our ten-LD traffic reporting zone after passing Earth at 1.49 LD and the Moon at 1.15 LD a few days ago. Today's DOU MPEC has first follow-up for inbound 2017 SX17 and 2017 SS16, along with continuing follow-up for outbound 2017 SH16 and approaching radar/NHATS target 2012 TC4, as well as distant 2007 DT103. And, among recently departed objects, the DOU has first follow-up for 2017 SU16, 2017 SR16, 2017 SD12, and risk-listed 2017 SF20 and 2017 SU17, plus continuing follow-up for 2017 SR10, 2017 RS2, and risk-listed 2017 SS12 and 2017 SQ2. The DOU also has astrometry from June 2011 for NHATS target 2007 DD.

Approaching (sorted by 10-LD bubble entry date)
0.13 LD Oct. 122012 TC4 15 m  < 10 LD Oct. 5, intruder, radar/NHATS target, risk - DOU
8.94 LD Oct. 112017 SB20 36 m  < 10 LD Oct. 8
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



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. "Distant" is used here to describe an object that has come within ten LD since A/CC began these traffic reports (2007) but is not presently so close. 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 1 October '17

The MPC's NEO Confirmation Page has 98 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 98 objects listed. Of these, 57 were "one nighters." So far The Tracking News has counted a total of 127 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 October '17

Minor Planet Electronic Circulars

As of last check at 2358 UTC, there have been ten MPECs posted today from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


MPEC 2017-T10 - "16:25 UT" - 2017 SB21


MPEC 2017-T09 - "16:20 UT" - 2017 SA21


MPEC 2017-T08 - "14:44 UT" - 2017 SZ20


MPEC 2017-T07 - "14:40 UT" - 2017 SY20


MPEC 2017-T06 - "14:35 UT" - 2017 SX20


MPEC 2017-T05 - "14:30 UT" - 2017 SW20


MPEC 2017-T04 - "14:25 UT" - 2017 SV20


MPEC 2017-T03 - "14:21 UT" - 2017 SU20


MPEC 2017-T02 - "14:15 UT" - 2017 ST20


<< DOU on 1 Oct. '17 >>  MPEC 2017-T01 - "12:10 UT" - Daily Orbit Update

Observers  on 1 October '17

A total of 25 observers appear in today's MPECs.

CodeObserver / observatory
H21Astronomical Research Obs. Westfield in Illinois, 15 in MPECs 2017-T01, 2017-T02, 2017-T08 & 2017-T10 -- 2017 SZ20, 2017 ST20, 2017 SR10, 2017 SO10, 2017 SH10, 2017 SB21, 2017 RY15, 2017 RX15, 2017 RV15, 2017 RU15, 2017 RU1, 2017 RU, 2017 RR15, 2017 RQ2, 2017 QV34
T05ATLAS Haleakala in Hawaii, 24 in MPEC 2017-T01 -- 2017 RV1, 2017 PR25, 2017 MY3, 2004 TD10, 2004 SS, 96631, 68348, 66146, 53319, 495858, 495848, 244977, 21374, 190166, 162566, 15817, 142464, 138911, 11405, 8035, 7977, 5143, 3288, 1980
T08ATLAS Mauna Loa in Hawaii, 9 in MPEC 2017-T01 -- 2017 SN2, 2017 RL, 2014 YC15, 2008 MH1, 1999 AF4, 329520, 294739, 162273, 3122
Z84Calar Alto Schmidt in Spain, 1 in MPEC 2017-T08 -- 2017 SZ20
160Castelmartini Obs. in Italy, 17 in MPEC 2017-T01 -- 2017 SN2, 2017 RV1, 2017 PJ26, 2017 OP68, 2016 AA9, 2014 YC15, 2008 MH1, 2004 TQ13, 2004 SS, 96631, 90075, 55408, 496005, 333888, 265962, 162998, 143624
703Catalina Sky Survey (CSS) in Arizona, 18 in MPECs 2017-T01, 2017-T06 & 2017-T09 -- 2017 SX20, 2017 SA21, 2017 OP68, 2014 YC15, 2013 AP60, 2008 MH1, 1999 AF4, 99907, 374851, 329520, 322763, 31221, 294739, 209924, 20086, 137078, 10165, 4197
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. in Chile, 1 in MPEC 2017-T05 -- 2017 SW20
K88GINOP-KHK in Hungary, 3 in MPEC 2017-T01 -- 2017 SN2, 2017 RV1, 2017 RR15
W19Kalamazoo Obs. in Michigan, 1 in MPEC 2017-T01 -- 3122
695^Spacewatch via Kitt Peak Natl. Obs. (KPNO) in Arizona, 9 in MPECs 2017-T01 & 2017-T03 -- 2017 SU20, 2017 SQ2, 2017 SM14, 2017 SF20, 2017 PL26, 2017 OP19, 2017 NM6, 2017 BL30, 2014 QO296
K91LCO Sutherland A in South Africa, 1 in MPEC 2017-T05 -- 2017 SW20
K95MASTER-II Sutherland in South Africa, 1 in MPEC 2017-T01 -- 65679
G96Mt. Lemmon Survey (MLS) in Arizona, 17 in MPECs 2017-T01, 2017-T06, 2017-T07, 2017-T08 & 2017-T09 -- 2017 SZ20, 2017 SY20, 2017 SY11, 2017 SX20, 2017 SV11, 2017 ST14, 2017 SP14, 2017 SL17, 2017 SA21, 2017 RR15, 2014 WP365, 471956, 415027, 26663, 222073, 220909, 142563
C47Nonndorf Obs. in Austria, 1 in MPEC 2017-T01 -- 2017 SN2
G34Oberfrauendorf Obs. in Germany, 1 in MPEC 2017-T01 -- 2017 RV1
F51Pan-STARRS 1 (PS1) in Hawaii, 23 in MPECs 2017-T01, 2017-T02, 2017-T03, 2017-T04, 2017-T05, 2017-T06, 2017-T09 & 2017-T10 -- 2017 SX20, 2017 SW20, 2017 SW14, 2017 SV20, 2017 SU20, 2017 ST20, 2017 ST16, 2017 SM12, 2017 SB21, 2017 SA21, 2017 QW32, 2017 QR17, 2017 QL18, 2017 PC27, 2012 SQ56, 2010 KY39, 2007 DT103, 96744, 408792, 333888, 329291, 23714, 142563
W71Rand II Obs. in New York, 2 in MPEC 2017-T01 -- 2017 SS12, 2017 SN2
B74Santa Maria de Montmagastrell Obs. in Spain, 1 in MPEC 2017-T01 -- 1993 RA
691Spacewatch 0.9m telescope in Arizona, 16 in MPECs 2017-T01 & 2017-T04 -- 2017 SX17, 2017 SX11, 2017 SW14, 2017 SV20, 2017 SS12, 2017 SO16, 2017 SL17, 2017 SK16, 2017 SE2, 2017 RR15, 2017 RO2, 2017 PS25, 2017 MO7, 223456, 141851, 11500
291Spacewatch 1.8m telescope in Arizona, 12 in MPECs 2017-T01, 2017-T02, 2017-T03, 2017-T04 & 2017-T09 -- 2017 SX17, 2017 SV20, 2017 SU20, 2017 SU17, 2017 ST20, 2017 SS12, 2017 SN10, 2017 SL17, 2017 SE14, 2017 SA21, 2017 OP19, 1998 WP7
V78Spirit Marsh Obs. in Minnesota, 1 in MPEC 2017-T01 -- 3122
I52Steward Obs. Mt. Lemmon Station in Arizona, 23 in MPECs 2017-T01, 2017-T05, 2017-T06, 2017-T07 & 2017-T08 -- 2017 SZ20, 2017 SY20, 2017 SX20, 2017 SW20, 2017 SV14, 2017 SU17, 2017 SU16, 2017 SU14, 2017 SS16, 2017 SR16, 2017 SQ14, 2017 SQ10, 2017 SP10, 2017 SN16, 2017 SM16, 2017 SL16, 2017 SK12, 2017 SH16, 2017 SF12, 2017 SD12, 2017 RT1, 2017 RS2, 2012 VF82
926Tenagra II Obs. in Arizona, 14 in MPECs 2017-T01, 2017-T02, 2017-T05, 2017-T06, 2017-T07, 2017-T08, 2017-T09 & 2017-T10 -- 2017 SZ20, 2017 SY20, 2017 SX20, 2017 SW20, 2017 SU11, 2017 ST20, 2017 ST14, 2017 SS16, 2017 SO10, 2017 SN14, 2017 SH16, 2017 SB21, 2017 SA21, 2017 GS6
B18Terskol Obs. in Russia, 1 in MPEC 2017-T01 -- 2012 TC4
T09UH/Tholen NEO Follow-Up Subaru Telescope in Hawaii, 1 in MPEC 2017-T01 -- 2007 DD
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 1 October '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 SA21JPL Sentry18182056-205614.036e-07-7.94-7.940JPL: Computed at 10:49 today Pacific time based on 29 observations spanning 2.0206 days (2017-Sep-29.34186 to 2017-Oct-01.3625). Diameter approximately 0.007 km. from weighted mean H=28.33.
2017 SV20JPL Sentry16322071-210572.43895e-07-3.61-3.670JPL: Computed at 09:02 today Pacific time based on 14 observations spanning 4.7821 days (2017-Sep-26.59876 to 2017-Oct-01.38086). Diameter approximately 0.610 km. from weighted mean H=18.74.
2017 SF20JPL Sentry15532034-203411.340e-04-5.03-5.030JPL: Computed at 08:38 today Pacific time based on 24 observations spanning 2.9882 days (2017-Sep-28.36701 to 2017-Oct-01.35517). Diameter approximately 0.007 km. from weighted mean H=28.30.
2017 SU17JPL Sentry15532069-2117292.60191e-05-6.32-6.830JPL: Computed at 08:39 today Pacific time based on 29 observations spanning 4.8292 days (2017-Sep-26.44444 to 2017-Oct-01.2736). Diameter approximately 0.009 km. from weighted mean H=27.99.
2017 SN14JPL Sentry1632R E M O V E DJPL: Risk listing removed at 1556 UTC today.
2017 SM14JPL Sentry1553R E M O V E DJPL: Risk listing removed at 1540 UTC today.
2017 SS12JPL Sentry16322074-211388.833e-07-7.30-7.590JPL: Computed at 09:26 today Pacific time based on 84 observations spanning 5.9288 days (2017-Sep-25.23585 to 2017-Oct-01.16466). Diameter approximately 0.013 km. from weighted mean H=27.11.
2017 PL26JPL Sentry15532100-211634.915e-07-5.25-5.340JPL: Computed at 07:56 today Pacific time based on 208 observations spanning 100.97 days (2017-Jun-21.52716 to 2017-Sep-30.49623). Diameter approximately 0.130 km. from weighted mean H=22.13.

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 October '17

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

2048Generated Traffic Report
1818Noted that JPL Sentry has posted 2017 SA21 as an impact risk - see above
1632Noted that JPL Sentry has removed 2017 SN14 as an impact risk - see above
Noted that JPL Sentry has updated its 2017 SS12 risk assessment - see above
Noted that JPL Sentry has posted 2017 SV20 as an impact risk - see above
Grabbed MPEC 2017-T09 - 2017 SA21 - see above
Grabbed MPEC 2017-T10 - 2017 SB21 - see above
1553Noted that JPL Sentry has updated its 2017 PL26 risk assessment - see above
Noted that JPL Sentry has updated its 2017 SF20 risk assessment - see above
Noted that JPL Sentry has removed 2017 SM14 as an impact risk - see above
Noted that JPL Sentry has updated its 2017 SU17 risk assessment - see above
Grabbed MPEC 2017-T01 - Daily Orbit Update - see above
Grabbed MPEC 2017-T02 - 2017 ST20 - see above
Grabbed MPEC 2017-T03 - 2017 SU20 - see above
Grabbed MPEC 2017-T04 - 2017 SV20 - see above
Grabbed MPEC 2017-T05 - 2017 SW20 - see above
Grabbed MPEC 2017-T06 - 2017 SX20 - see above
Grabbed MPEC 2017-T07 - 2017 SY20 - see above
Grabbed MPEC 2017-T08 - 2017 SZ20 - see above