Contents  on 24 April '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 24 April '17

Six objects reported inside ten LD

There are six Solar-System small bodies reported to be less than ten lunar distances (LD) from Earth today. Intruder 2017 HV2 starts the day inside the Earth-Moon system and flies out to 2.29 LD, passing the Moon at 0.90 LD at 0710 UTC. Further away two objects come their closest to our planet this time around at roughly similar distances and times: 2017 HY at 3.24 LD at 0955 UTC and 2017 HB1 at 3.59 LD at 0906 UTC.

Earth passage I D ~Size Distance Today  Notes
0.33 LD yesterday2017 HV2 6 m  0.37 to 2.29 LD intruder today, Moon closest 0.90 LD at 0710 UTC - DOU
3.17 LD April 202017 HU2 23 m  4.25 to 4.90 LD DOU
3.24 LD today2017 HY 11 m  3.24 LD Earth closest at 0955 UTC - DOU
3.59 LD today2017 HB1 19 m  3.59 LD Earth closest at 0906 UTC - DOU
3.76 LD April 222017 HD 15 m  5.16 to 7.32 LD DOU
6.07 LD yesterday2017 HH1 26 m  6.26 to 8.28 LD DOU
Approaching
7.93 LD May 292017 CS 446 m  < 10 LD May 26, radar target
9.18 LD April 272017 HW2 17 m  < 10 LD tomorrow

This report was generated at 1940 UTC with follow-up in today's DOU MPEC for all six objects inside ten LD today (see table) as well as for six departed objects: 2017 HL1, 2017 HG, 2017 HF, risk-listed intruder 2017 HJ, NHATS target 2017 DC36, and radar target 2014 JO25.



Notes: Ten times the distance to the Moon (ten LD) has no astronomical importance but is a useful boundary for reporting on transient natural objects that approach the actually significant 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 24 April '17

The MPC's NEO Confirmation Page has 38 listings

When last checked at 2358 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 38 objects listed. Of these, fifteen were "one nighters." So far The Tracking News has counted a total of 42 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 24 April '17

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 24 Apr. '17 >>  MPEC 2017-H56 - "11:59 UT" - Daily Orbit Update

Observers  on 24 April '17

A total of 31 observers appear in today's MPEC.

CodeObserver / observatory
705"Kristie Nault via Apache Point Obs. in New Mexico, 12 in MPEC 2017-H56 -- 2017 HH, 2017 HG, 2017 HF, 2017 HD, 2017 GP6, 2017 GO7, 2017 FU128, 2017 FQ90, 2017 FH90, 2017 FE157, 2017 FC157, 2015 KJ122
H21Astronomical Research Obs. Westfield in Illinois, 15 in MPEC 2017-H56 -- 2017 GR6, 2017 GR5, 2017 GM6, 2017 FR101, 2017 FO128, 2017 FN90, 2017 FF101, 2017 EE23, 2017 DC36, 2017 DB109, 2016 TY92, 2013 LE16, 2010 TU54, 469219, 4596
B66Casasco Obs. in Italy, 3 in MPEC 2017-H56 -- 90075, 89830, 391508
160Castelmartini Obs. in Italy, 11 in MPEC 2017-H56 -- 90075, 53319, 475665, 456651, 448003, 427643, 188174, 137170, 7888, 3352, 1036
703Catalina Sky Survey (CSS) in Arizona, 22 in MPEC 2017-H56 -- 2017 GT5, 2017 GB8, 2017 DT37, 2016 WO1, 2012 HN13, 2011 ED78, 90075, 53319, 456651, 427643, 405427, 39796, 252091, 248083, 215588, 175189, 159560, 138359, 137158, 7480, 5604, 3552
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 14 in MPEC 2017-H56 -- 2017 HX, 2017 HJ2, 2017 HJ, 2017 GW6, 2017 GU6, 2017 GO6, 2017 FP, 2017 FO2, 2017 FM63, 2017 EU, 2016 XM, 2016 UZ56, 2016 TH56, 2016 NV15
B92Chinon Obs. in France, 1 in MPEC 2017-H56 -- 2014 JO25
J27El Guijo Obs. in Spain, 1 in MPEC 2017-H56 -- 474231
157Frasso Sabino Obs. in Italy, 2 in MPEC 2017-H56 -- 2017 GT5, 2017 FJ90
J95Great Shefford Obs. in England, 1 in MPEC 2017-H56 -- 2017 HV2
Q62`Steven M. Tilley in Louisiana via iTelescope Obs. Siding Spring in New South Wales, 1 in MPEC 2017-H56 -- 2017 GU6
130Lumezzane Obs. in Italy, 2 in MPEC 2017-H56 -- 374038, 5604
K95MASTER-II Sutherland in South Africa, 1 in MPEC 2017-H56 -- 163902
B67Mirasteilas Obs. in Switzerland, 3 in MPEC 2017-H56 -- 2017 DS35, 2016 HJ19, 2010 JH88
213Montcabre Obs. in Spain, 1 in MPEC 2017-H56 -- 2014 JO25
474Mt. John Obs. in New Zealand, 14 in MPEC 2017-H56 -- 2017 HU2, 2017 HU, 2017 HL1, 2017 HK2, 2017 HJ2, 2017 GL7, 2017 GL6, 2017 GK7, 2017 FL128, 2017 EV2, 2017 ES2, 2017 ED4, 2017 BL6, 2014 UD206
G96Mt. Lemmon Survey (MLS) in Arizona, 21 in MPEC 2017-H56 -- 2017 HK1, 2017 GS4, 2017 FH128, 2017 FE1, 2017 DT37, 2016 WO1, 2016 HJ19, 2015 FN118, 2014 GD45, 2012 HL31, 2011 ED78, 2001 HW7, 456651, 405427, 374038, 250620, 240320, 234061, 154988, 154652, 137158
Z80Northolt Branch Obs. in England, 2 in MPEC 2017-H56 -- 2017 GB8, 2014 JO25
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 13 in MPEC 2017-H56 -- 2017 GT5, 2017 GB8, 2017 FJ90, 2017 FH101, 2017 DT37, 2017 AC5, 2014 JO25, 2011 GL44, 2011 ED78, 2006 UM, 2005 GB120, 2000 AF205, 1998 HK1
D29Purple Mtn. Obs. Xuyi Station in China, 8 in MPEC 2017-H56 -- 2017 GQ6, 2010 VE1, 2005 GL9, 2003 OV, 163696, 100926, 5604, 2329
W25RMS Obs., 12 in MPEC 2017-H56 -- 2017 HU, 2017 HH2, 2017 HH1, 2017 HB1, 2017 GW6, 2017 GK4, 2017 GB8, 2017 FS101, 2017 FG128, 260141, 159560, 138155
L04ROASTERR-1 in Romania, 1 in MPEC 2017-H56 -- 2014 JO25
619Sabadell Obs. in Spain, 1 in MPEC 2017-H56 -- 2014 JO25
H36Sandlot Obs. in Kansas, 1 in MPEC 2017-H56 -- 2017 GU6
Y00SONEAR in Brazil, 1 in MPEC 2017-H56 -- 2014 JO25
691Spacewatch 0.9m telescope in Arizona, 18 in MPEC 2017-H56 -- 2017 GW6, 2017 GQ5, 2017 GL6, 2017 FP64, 2017 FM63, 2017 FM128, 2017 FJ90, 2017 FE128, 2017 FE101, 2017 ES22, 2017 AP20, 2016 XH2, 2016 WO1, 2016 QC84, 2016 LE9, 2014 NA64, 2000 GW127, 203217
291Spacewatch 1.8m telescope in Arizona, 12 in MPEC 2017-H56 -- 2017 HG2, 2017 GN4, 2017 FR128, 2017 FQ64, 2017 FP91, 2017 FP, 2017 FK128, 2017 FC157, 2017 DB36, 2014 NA64, 2014 JG78, 2008 SQ7
V78Spirit Marsh Obs. in Minnesota, 1 in MPEC 2017-H56 -- 2014 JO25
I52Steward Obs. Mt. Lemmon Station in Arizona, 4 in MPEC 2017-H56 -- 2017 HX, 2017 HK2, 2017 HK1, 2017 FQ101
926Tenagra II Obs. in Arizona, 12 in MPEC 2017-H56 -- 2017 HY, 2017 HV2, 2017 HH2, 2017 HH, 2017 HB1, 2017 GU6, 2017 GK4, 2017 GB8, 2017 FS101, 2017 FH101, 2017 FG128, 2017 BL6
Z52The Studios Obs., 1 in MPEC 2017-H56 -- 11398
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 24 April '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 HT2NEODyS16042024-21171131.48e-06-2.35-2.980NEODyS: "Based on 70 optical observations (of which 0 are rejected as outliers) from 2017-04-20.308 to 2017-04-23.344."
2017 HJJPL Sentry17302070-2117234.65326e-06-6.61-7.450JPL #2 for the day: Computed at 10:26 today Pacific time based on 51 observations spanning 6.7231 days (2017-Apr-17.42568 to 2017-Apr-24.14873). Diameter approximately 0.011 km. from weighted mean H=27.42.
NEODyS16042070-2117198.44e-06-6.34-6.480NEODyS: "Based on 54 optical observations (of which 1 are rejected as outliers) from 2017-04-17.426 to 2017-04-22.452."
2017 GF8JPL Sentry17012047-211056.4651e-09-7.48-7.660JPL: Computed at 09:44 today Pacific time based on 6 observations spanning 1.4258 days (2017-Apr-03.46618 to 2017-Apr-04.891947). Diameter approximately 0.075 km. from weighted mean H=23.28.
2017 GM6NEODyS1604R E M O V E D-
JPL Sentry16042111-211111.892e-07-7.65-7.650JPL: Computed at 08:11 today Pacific time based on 43 observations spanning 17.881 days (2017-Apr-05.34221 to 2017-Apr-23.223016). Diameter approximately 0.022 km. from weighted mean H=25.90.
2017 FD157NEODyS1604R E M O V E D-
2017 FO128JPL Sentry17302104-210932.4216e-07-5.54-5.820JPL #2 for the day: Computed at 10:15 today Pacific time based on 79 observations spanning 24.101 days (2017-Mar-30.26183 to 2017-Apr-23.36277). Diameter approximately 0.110 km. from weighted mean H=22.44.
NEODyS16042104-210942.71e-07-5.49-5.60NEODyS: "Based on 84 optical observations (of which 2 are rejected as outliers) from 2017-03-30.263 to 2017-04-23.364."
2017 FN128NEODyS1604R E M O V E D-
2016 JR38JPL Sentry16042084-208411.118e-10-8.62-8.620JPL: Computed at 01:48 today Pacific time based on 8 observations spanning 4.9701 days (2016-May-03.34485 to 2016-May-08.314961). Diameter approximately 0.140 km. from weighted mean H=21.90.
2016 HF3JPL Sentry18302078-207813.558e-06-5.54-5.540JPL: Computed at 11:16 today Pacific time based on 294 observations spanning 42.026 days (2016-Apr-27.30971 to 2016-Jun-08.33587). Diameter approximately 0.038 km. from weighted mean H=24.76.
2014 HV2JPL Sentry16042116-211611.246e-07-7.64-7.640JPL: Computed at 23:54 April 23rd Pacific time based on 69 observations spanning 5.8084 days (2014-Apr-22.37164 to 2014-Apr-28.18008). Diameter approximately 0.021 km. from weighted mean H=26.01.

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 24 April '17

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

1940Generated Traffic Report
1830Noted that JPL Sentry has reposted 2016 HF3 as an impact risk - see above
1730Noted that JPL Sentry has updated its 2017 FO128 risk assessment - see above
Noted that JPL Sentry has updated its 2017 HJ risk assessment - see above
1701Noted that JPL Sentry has posted 2017 GF8 as an impact risk - see above
1604Noted that JPL Sentry has reposted 2014 HV2 as an impact risk - see above
Noted that JPL Sentry has reposted 2016 JR38 as an impact risk - see above
Noted that NEODyS has removed 2017 FD157 as an impact risk - see above
Noted that NEODyS has removed 2017 FN128 as an impact risk - see above
Noted that JPL Sentry has updated its 2017 FO128 risk assessment - see above
Noted that NEODyS has updated its 2017 FO128 risk assessment - see above
Noted that JPL Sentry has updated its 2017 GM6 risk assessment - see above
Noted that NEODyS has removed 2017 GM6 as an impact risk - see above
Noted that JPL Sentry has updated its 2017 HJ risk assessment - see above
Noted that NEODyS has updated its 2017 HJ risk assessment - see above
Noted that NEODyS has posted 2017 HT2 as an impact risk - see above
Grabbed MPEC 2017-H56 - Daily Orbit Update - see above