Contents  on 25 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 25 April '17

Seven objects reported inside ten LD

Today there are seven asteroids reported inside ten lunar distances (LD) of our home world. Nearest of these is intruder 2017 HV2, which exits Earth's SOI (sphere of gravitational influence), going out from 2.29 to 4.36 LD.

Earth passage I D ~Size Distance Today  Notes
0.33 LD April 232017 HV2 6 m  2.29 to 4.36 LD intruder, exits Earth SOI
3.17 LD April 202017 HU2 23 m  4.90 to 5.62 LD DOU
3.24 LD yesterday2017 HY 11 m  3.38 to 4.18 LD
3.59 LD yesterday2017 HB1 19 m  3.72 to 4.42 LD DOU
3.76 LD April 222017 HD 15 m  7.32 to 9.78 LD
6.07 LD April 232017 HH1 26 m  8.28 to 11.47 LD exits ten LD
9.18 LD April 272017 HW2 17 m  9.98 from 10.94 LD enters ten LD
Approaching
7.93 LD May 292017 CS 446 m  < 10 LD May 26, radar target

This report was generated at 1910 UTC with follow-up in today's DOU MPEC for two objects active in the traffic table here plus two that have departed: risk-listed intruder 2017 HJ 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.

Radar Astrometry  on 25 April '17

Radar observation of one object

The JPL Solar System Dynamics Group Radar Astrometry database has added or updated the following small-body radar observing work:


Data update noted at 2359 UTC when the database was dated 25 April

NEOCP Activity  on 25 April '17

The MPC's NEO Confirmation Page has 41 listings

When last checked at 2327 UTC today, the Minor Planet Center's Near Earth Object discovery Confirmation Page (NEOCP) had 41 objects listed. Of these, 26 were "one nighters." The Tracking News counted a total of 53 listings on the NEOCP on this day.

New MPECs  on 25 April '17

Minor Planet Electronic Circulars

There was one MPEC posted this day from the International Astronomical Union's Minor Planet Center in Cambridge, Massachusetts.


<< DOU on 25 Apr. '17 >>  MPEC 2017-H57 - "11:59 UT" - Daily Orbit Update

Observers  on 25 April '17

A total of 29 observers appeared in this day's MPEC.

CodeObserver / observatory
251Arecibo in Puerto Rico, 1 in radar -- 2014 JO25
H21Astronomical Research Obs. Westfield in Illinois, 21 in MPEC 2017-H57 -- 2017 HK1, 2017 HH, 2017 HF1, 2017 HC1, 2017 GW6, 2017 GT5, 2017 GR5, 2017 GM7, 2017 GK4, 2017 GB8, 2017 FR101, 2017 FM128, 2017 FF101, 2017 FE128, 2017 DT37, 2017 DS35, 2017 DB36, 2016 WK8, 2016 LE51, 2016 AH193, 175729
160Castelmartini Obs. in Italy, 14 in MPEC 2017-H57 -- 2017 GT5, 2017 GB8, 2017 AC5, 2011 ED78, 1998 HK1, 484795, 474231, 405427, 252091, 220124, 138359, 10636, 5626, 5604
703Catalina Sky Survey (CSS) in Arizona, 27 in MPEC 2017-H57 -- 2017 GW6, 2017 GU6, 2017 DS35, 2014 JO25, 2011 GL44, 2000 AF205, 1998 HK1, 484795, 475665, 456651, 413002, 370307, 276468, 222073, 190166, 163696, 162452, 143624, 138404, 138155, 138095, 7358, 4954, 4055, 3752, 3552, 1036
807|Robert Holmes in Illinois via Cerro Tololo Inter-American Obs. (CTIO) in Chile, 4 in MPEC 2017-H57 -- 2017 HG2, 2017 FK128, 2016 WG10, 2016 UZ56
I39Cruz del Sur Obs. in Argentina, 1 in MPEC 2017-H57 -- 2014 JO25
J04ESA Optical Ground Station (ESA OGS) in the Canary Islands, 4 in MPEC 2017-H57 -- 2017 HT2, 2017 HJ, 2017 GM7, 2017 FO128
157Frasso Sabino Obs. in Italy, 1 in MPEC 2017-H57 -- 2008 YA
253Goldstone DSS-14 70m antenna in southern California, 1 in radar -- 2014 JO25
J95Great Shefford Obs. in England, 1 in MPEC 2017-H57 -- 2017 HB1
K78Iota Scorpii Obs., 1 in MPEC 2017-H57 -- 391508
Q63LCOGT Siding Spring A in New South Wales, 1 in MPEC 2017-H57 -- 2017 HJ
C41MASTER-II Kislovodsk in Russia, 1 in MPEC 2017-H57 -- 433
K89MPC code K89, 1 in MPEC 2017-H57 -- 138155
W63MPC code W63, 1 in MPEC 2017-H57 -- 2014 JO25
G96Mt. Lemmon Survey (MLS) in Arizona, 10 in MPEC 2017-H57 -- 2017 GT6, 2017 GS6, 2017 GQ6, 2017 FH90, 2016 YF11, 2010 JH88, 2005 GB120, 2004 JQ1, 482244, 474425
C47Nonndorf Obs. in Austria, 1 in MPEC 2017-H57 -- 2014 JO25
G34Oberfrauendorf Obs. in Germany, 1 in MPEC 2017-H57 -- 2014 JO25
C23Olmen Obs. in Belgium, 1 in MPEC 2017-H57 -- 2014 JO25
F51Pan-STARRS 1 in Hawaii, 1 in MPEC 2017-H57 -- 2017 HH
H45Petit Jean Mtn. South Obs. (PJMSO) in Arkansas, 15 in MPEC 2017-H57 -- 2017 GB8, 2017 FH101, 2017 DT37, 2017 DS35, 2017 AC5, 2014 JO25, 2011 GL44, 2011 ED78, 2010 JH88, 2005 GB120, 2000 AF205, 1998 HK1, 474179, 252091, 11398
122Pises Obs. in France, 4 in MPEC 2017-H57 -- 2012 HN8, 474425, 339492, 136582
L04ROASTERR-1 in Romania, 1 in MPEC 2017-H57 -- 2014 JO25
B74Santa Maria de Montmagastrell Obs. in Spain, 2 in MPEC 2017-H57 -- 2017 GT5, 2014 JO25
G403Tony Evans in Portugal via Slooh.com Canary Islands Obs. in the Canary Islands, 1 in MPEC 2017-H57 -- 2017 FH101
691Spacewatch 0.9m telescope in Arizona, 3 in MPEC 2017-H57 -- 2017 HK1, 2015 KJ122, 2011 GL44
926Tenagra II Obs. in Arizona, 8 in MPEC 2017-H57 -- 2017 HU2, 2017 HH2, 2017 HB1, 2017 GK4, 2017 FS101, 2017 FH101, 2017 FG128, 2016 XH2
T12UH/Tholen NEO Follow-Up 2.24m Telescope in Hawaii, 2 in MPEC 2017-H57 -- 2017 FR90, 2015 KJ122
C51WISE in Earth polar orbit, 2 in MPEC 2017-H57 -- 474179, 370702
For a list of all participating observatories that have Web addresses, see A/CC's Observatory Links page.

Impact Risk Monitoring  on 25 April '17

Summary Risk Table for Risk Assessments Updated Today   (last checks: NEODyS at 2327 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 HT2JPL Sentry16212024-2116841.8419398e-06-2.34-2.830JPL: Computed at 08:09 today Pacific time based on 37 observations spanning 4.6458 days (2017-Apr-20.30727 to 2017-Apr-24.953023). Diameter approximately 0.736 km. from weighted mean H=18.31.
2017 HJJPL Sentry16212070-2117254.18396e-06-6.66-7.540JPL: Computed at 08:22 today Pacific time based on 56 observations spanning 7.5571 days (2017-Apr-17.42568 to 2017-Apr-24.982772). Diameter approximately 0.011 km. from weighted mean H=27.43.
NEODyS16212070-2117198.4e-06-6.33-6.480NEODyS: "Based on 57 optical observations (of which 1 are rejected as outliers) from 2017-04-17.426 to 2017-04-24.150."
2017 GM7JPL Sentry1621R E M O V E DJPL: Risk listing removed at 1458 UTC today.
2017 FO128JPL Sentry16212104-210931.09125e-07-5.89-5.950JPL: Computed at 08:11 today Pacific time based on 82 observations spanning 25.655 days (2017-Mar-30.26183 to 2017-Apr-24.916408). Diameter approximately 0.110 km. from weighted mean H=22.43.
NEODyS16212104-210951.68e-07-5.70-5.840NEODyS: "Based on 87 optical observations (of which 2 are rejected as outliers) from 2017-03-30.263 to 2017-04-23.364."
2014 UX34JPL Sentry16212084-208411.274e-08-6.37-6.370JPL: Computed at 22:53 April 24th Pacific time based on 55 observations spanning 36.925 days (2014-Oct-23.33075 to 2014-Nov-29.25596). Diameter approximately 0.110 km. from weighted mean H=22.37.
2013 VD17JPL Sentry16212075-207516.132e-09-9.29-9.290JPL: Computed at 06:34 today Pacific time based on 26 observations spanning 26.293 days (2013-Nov-14.24215 to 2013-Dec-10.53514). Diameter approximately 0.013 km. from weighted mean H=27.11.

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 25 April '17

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

2359Noted Radar Astrometry database update - see above
1910Generated Traffic Report
1621Noted that JPL Sentry has reposted 2013 VD17 as an impact risk - see above
Noted that JPL Sentry has reposted 2014 UX34 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 removed 2017 GM7 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 JPL Sentry has updated its 2017 HT2 risk assessment - see above
Grabbed MPEC 2017-H57 - Daily Orbit Update - see above