The NEO 2016 WJ1 Has Been Removed from the Sentry Risk Table--Neodys Risk Table List 3 Possible Impacts 2106-2115.

On December 2, 2016 at 21:33(UTC) NASA JPL removed the NEO 2016 WJ1 from the Sentry Risk Table. Whenever an object is posted to one the risk lists (especially if it has a Torino Scale 1 or greater) and it is observable, observers will take a particular interest in it. In the case of 2016 WJ1 many follow-up observations where made and  there was a search in archives for precovery observations. From  November 24, 2016  to December 2, 2016  through the work of many observers from around the world the number of optical observations went from 68  to 240 and  the data-arc span went from 5 days to  4899 days (13.41 yr). This allowed  for the calculation of orbital elements with lower uncertainty and NASA JPL rule out  potential impacts well into the future. Notice: Neodys risk table list 3 possible impacts 2106-2115.

Background
(as of 2016-12-03 ) 

• Object: 2016 WJ1 
• Approximate Diameter: 140 m - 310 m (459.318 feet to 1017.06 feet)(Absolute Magnitude: H= 21.382)
• Orbit Type: Apollo [NEO]- Potentially Hazardous Asteroid
• On the Sentry Risk Table: No Removed on 2016-12-02 21:33
• On the NEODyS CLOMON2 risk page: yes
•  NOTE this is NOT a prediction of an impact but rather a statement there is insufficient observational data rule out an impact -- for information read  Understanding Risk Pages by Jon Giorgini
• Torino Scale(NEODyS CLOMON2): 0
• The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage."
• First(Precovery) Observation was made: 2003 07 04.605261
• First(Precovery) Observed By: Mauna Kea (MPC Code 568) The Precovery M.P.E.C.:MPEC 2016-X21 : 2016 WJ1
• Discovery (First) observation was made: 2016 11 19.46522
• Discovery (First )observed by: Mt. Lemmon Survey (MPC Code G96) The Discovery M.P.E.C.: MPEC 2016-W38 : 2016 WJ1
• Last Observation(publish): 2016 12 02.87233
  (by Nonndorf, Austria. (MPC Code C47 )
• Data-Arc Span(publish) : 4900 days (13.42 yr)
• Number of Optical Observations(published): 257
• Observatories Reporting (Published) Observations(MPC Code):
• (151) Eschenberg Observatory, Winterthur Switzerland.  
• (160) Castelmartini,Italy.
• (203) GiaGa Observatory,Italy.
• (246) Klet Observatory-KLENOT, Czech Republic.
• (291) LPL/Spacewatch II,US/Arizona. 
• (568) Mauna Kea,US/Hawaii.
• (691) Steward Observatory, Kitt Peak-Spacewatch, US/Arizona.
• (926) Tenagra II Observatory, Nogales,US/Arizona.  
• (958) Observatoire de Dax, France.
• (A17) Guidestar Observatory, Weinheim,Germany.
• (A48) Povegliano Veronese,Italy.
• (C47) Nonndorf, Austria.
• (C77) Bernezzo Observatory, Italy.
• (E10) Siding Spring-Faulkes Telescope South, Australia/NSW.
• (F51) Pan-STARRS 1, Haleakala, US/Hawaii.
• (G96) Mt. Lemmon Survey, US/Arizona.
• (H06) iTelescope Observatory, Mayhill, US/New Mexico.  
• (H21) Astronomical Research Observatory, Westfield, US/Illinois.
• (H45) Arkansas Sky Obs., Petit Jean Mountain South, US/Arkansas.
• (I52) Steward Observatory, Mt. Lemmon Station,US/Arizona.
• (J04) ESA Optical Ground Station, Tenerife, Canary Islands (Spain).
• (J69) North Observatory, Clanfield,UK.
• (K38) M57 Observatory, Saltrio,Italy.
• (K61) Rokycany Observatory,Czech Republic.
• (K65) Cesena,Italy.
• (K74) Muensterschwarzach Observatory, Schwarzach, Germany.
• (K88) GINOP-KHK, Piszkesteto, Hungary.
• (L04) ROASTERR-1 Observatory, Cluj-Napoca, Romania.
• (Q62) iTelescope Observatory, Siding Spring, Australia/NSW.
• (T05) ATLAS-HKO, Haleakala, US/Hawaii.
• (T12) Mauna Kea-UH/Tholen NEO Follow-U (2.24-m),US/Hawaii.
• (W25) RMS Observatory, Cincinnati,US/Ohio.
• (W88) Slooh.com Chile Observatory, La Dehesa,Chile.
• (Y28) OASI, Nova Itacuruba, Brazil.
• (Z80) Northolt Branch Observatory,UK..
• Perihelion Distance: 0.6654428764236301  (AU)
• Aphelion Distance: 2.013952506814137 (AU)
• Earth MOID: 0.000339358 AU (0.132 (LD)) or 31,545.297 miles (50,767.234 (KM))
• Close-Approach to Earth: Will safely pass Earth on 2016-December-16 at a Nominal Distance of  0.0538116295342834 (AU) (20.942 (LD)) or 5,004,610.672 miles (8,054,140.158 (KM))

To illustrate on how the addition of observation can lower the uncertainty of orbital elements here is three
screenshot of Find_Orb showing elements and their uncertainty

A screenshot of Find_Orb showing orbital elements and uncertainty

 before the addition of the precovery observation.

(2 observationobservation are rejected as outliers) 

Orbital elements:  2016 WJ1
   Perihelion 2017 Feb 7.453335 +/- 0.0146 TT = 10:52:48 (JD 2457791.953335)
Epoch 2017 Feb 16.0 TT = JDT 2457800.5   Earth MOID: 0.0004   Ve: 0.0023
M   5.42420715 +/- 0.0053           Ma: 0.0027                Find_Orb
n   0.63465774060 +/- 0.000456      Peri.   87.68828816 +/- 0.0057
a   1.34104390016 +/- 0.000642      Node    82.04709113 +/- 0.0023
e   0.5040907493 +/- 0.000384       Incl.    2.89419977 +/- 0.0022
P   1.55/567.22d           H 21.3   G  0.15   U  7.6  
q 0.66503607568 +/- 0.000196    Q 2.01705172465 +/- 0.00148
233 of 235 observations 2016 Nov. 19-Dec. 1; mean residual 0".32

A screenshot of Find_Orb showing orbital elements and uncertainty 

after the addition of the precovery observation.

(2 observationobservation are rejected as outliers) 

Orbital elements:  2016 WJ1
   Perihelion 2017 Feb 7.484044 +/- 0.000243 TT = 11:37:01 (JD 2457791.984044)
Epoch 2017 Feb 16.0 TT = JDT 2457800.5   Earth MOID: 0.0004   Ve: 0.0024
M   5.41286498 +/- 0.00015          Ma: 0.0027                Find_Orb
n   0.63561447057 +/- 1.52e-7       Peri.   87.67637253 +/- 0.00017
a   1.33969786518 +/- 2.14e-7       Node    82.05217334 +/- 0.00022
e   0.5032874712 +/- 8.64e-7        Incl.    2.88944734 +/- 0.000020
P   1.55/566.37d           H 21.3   G  0.15   U  2.3  
q 0.66544471439 +/- 1.26e-6    Q 2.01395101596 +/- 8.71e-7
238 of 240 observations 2003 July 4-2016 Dec. 1; mean residual 0".32

A screenshot of Find_Orb showing orbital elements and uncertainty 

with all published observation.

(2 observationobservation are rejected as outliers) 

Orbital elements:  2016 WJ1
   Perihelion 2017 Feb 7.484067 +/- 0.000172 TT = 11:37:03 (JD 2457791.984067)
Epoch 2017 Feb 16.0 TT = JDT 2457800.5   Earth MOID: 0.0004   Ve: 0.0024
M   5.41285007 +/- 0.00010          Ma: 0.0027                Find_Orb
n   0.63561448686 +/- 1.18e-7       Peri.   87.67634890 +/- 0.00015
a   1.33969784228 +/- 1.66e-7       Node    82.05222716 +/- 0.00017
e   0.5032875546 +/- 7.26e-7        Incl.    2.88944241 +/- 0.000019
P   1.55/566.37d           H 21.3   G  0.15   U  2.1  
q 0.66544459133 +/- 1.05e-6    Q 2.01395109323 +/- 7.49e-7
255 of 257 observations 2003 July 4-2016 Dec. 2; mean residual 0".31

 Useful Links: 

• Space Situational Awareness(ESA) -- 2016 WJ1
• Near Earth Objects Dynamic Site--2016 WJ1
• (MPC) Observations --2016 WJ1
• JPL Orbit Diagram --2016 WJ1 
• PHA 2016 WJ1 from M57( An Amateur Astrophotography Blog)
• Asteroid 2016 WJ1: to what extent is a threat?(in Italian a with translated to option)
• NEO Earth Close Approaches (JPL) (up coming)
• JPL's NEO Earth Close-Approaches  (Between 1900 A.D. and 2200 A.D- limited to encounters with  reasonably low uncertainty)
• The Tracking News
• NEO Coordination Centre 
• Speed of Light - Space - Distance Calculator
• Asteroid Hazards: The View from Space(MPC)
• Don’t fear apocalyptic asteroids: you’re safer than you think
• Understanding Risk Pages By Jon Giorgini
• Revised asteroid scale aids understanding of impact risk
• Near Earth Objects Scale Helps Risk Communication
• Dealing With the Impact Hazard: An International Project
• The Palermo Technical Impact Hazard Scale
• An Asteroid as Entered the Blogosphere… Should I Be Worried? A commentary by Steven M. Tilley
• International Asteroid Warning Network 
• Impact Risk Assessment: An Introduction - Near-Earth Object Program
• Hazardous NEO Technical Reviews
• Frequently Asked Questions For Impact Risk Assessment 
• How to Find an Impact Orbit for the Earth-Asteroid Collision
• The Asteroid/Comet Impact Hazard
• Whom should we call? Data policy for immediate impactors announcements
• NEO Search & Follow-Up
• NEOs' Science pages  by Livia Giacomini
• Torino Scale(JPL) 
• Find_Orb --- Orbit determination software - Project Pluto
• Guide to Minor Body Astrometry(MPC)

The NEO 2016 WJ1 on 2016-12-01 from Siding Spring - Australia

See The NEO 2016 WJ1 Has Been Removed from the Sentry Risk Table--Neodys Risk Table List 3 Possible Impacts 2106-2115.

NOTE with only 12 days data-arc span there is "little" known about the NEO 2016 WJ1 and the information in this post may become outdated. So one should always check the links for updates. Whenever an object is posted to one the risk lists (especially if it has a Torino Scale 1 or greater) and it is observable, observers will take a particular interest in it. In the coming days it is possible there will be more follow-up observations and a search in archives for precovery observations. It is MOST likely this object will be removed from the risk lists. It could take observations over one or more orbital periods before we can reliably say where it will be from 2030 to 2108.

Background
(as of 2016-12-01 9:50am CST) 

• Object: 2016 WJ1 
• Approximate Diameter: 140 m - 310 m (459.318 feet to 1017.06 feet)(Absolute Magnitude: H= 21.402)
• Orbit Type: Apollo [NEO]- Potentially Hazardous Asteroid
• On the Sentry Risk Table: yes  NO
•  NOTE this is NOT a prediction of an impact but rather a statement there is insufficient observational data rule out an impact -- for information read  Understanding Risk Pages by Jon Giorgini
•  Torino Scale(JPL): 1 
• "A routine discovery in which a pass near the Earth is predicted that poses no unusual level of danger. Current calculations show the chance of collision is extremely unlikely with no cause for public attention or public concern. New telescopic observations very likely will lead to re-assignment to Level 0"
• On the NEODyS CLOMON2 risk page: yes
• Torino Scale(NEODyS CLOMON2): 1
• First observation was made: 2016 11 19.46522
• First observed by: Mt. Lemmon Survey (MPC Code G96) The Discovery M.P.E.C.: MPEC 2016-W38 : 2016 WJ1
• Last Observation(publish): 2016 12 01.48096 (by iTelescope Observatory  (MPC Code Q62)
• Data-Arc Span(publish) : 12 days
• Number of Optical Observations(published): 222
• Observatories Reporting (Published) Observations(MPC Code):
• (151) Eschenberg Observatory, Winterthur, Switzerland. 
• (203) GiaGa Observatory, Italy.  
• (246) Klet Observatory-KLENOT, Czech Republic.  
• (291) LPL/Spacewatch II,Arizona,US. 
• (691) Steward Observatory, Kitt Peak-Spacewatch, Arizona,US.
• (926) Tenagra II Observatory, Nogales,Arizona,US. 
• (958) Observatoire de Dax,France.
• (A17) Guidestar Observatory, Weinheim, Germany.
• (A48) Povegliano Veronese,Italy.
• (C47) Nonndorf, Austria.
• (E10) Siding Spring-Faulkes Telescope South, NSW,Australia.
• (F51) Pan-STARRS 1, Haleakala,Hawaii,US. 
• (G96) Mt. Lemmon Survey, Arizona,US.
• (H06) iTelescope Observatory, Mayhill,New Mexico,US.
• (H21) Astronomical Research Observatory, Westfield,Illinois,US.
• (H45) Arkansas Sky Obs., Petit Jean Mountain South,Arizona,US. 
• (I52) Steward Observatory, Mt. Lemmon Station, Arizona,US.
• (J04) ESA Optical Ground Station, Tenerife, Canary Islands, Spain.
• (J69) North Observatory, Clanfield, UK.
• (K38) M57 Observatory, Saltrio, Italy.
• (K61) Rokycany Observatory,Czech Republic.
• (K65) Cesena Italy.
• (K74) Muensterschwarzach Observatory, Schwarzach, Germany.
• (K88) GINOP-KHK, Piszkesteto,Hungary.
• (L04) ROASTERR-1 Observatory, Cluj-Napoca,Romania.
• (Q62) iTelescope Observatory, Siding Spring, NSW,Australia.   
• (T05) ATLAS-HKO, Haleakala,Hawaii,US.
• (T12) Mauna Kea-UH/Tholen NEO Follow-U, Hawaii,US.
• (W88) Slooh.com Chile Observatory, La Dehesa,Chile.
• (Y28) OASI, Brazil.
• (Z80) Northolt Branch Observatory, UK.
.
• Perihelion Distance: .6653138187201434 (AU)
• Aphelion Distance: 2.01493605513458 (AU)
• Earth MOID: 0.000339608 AU (0.132 (LD)) or 31,568.536 miles (50,804.634 (KM))
• Close-Approach to Earth: Will safely pass Earth on 2016-December-16 at a Nominal Distance of  0.0538386015810167 (AU) (20.952 (LD)) or 5,004,610.672 miles (8,054,140.158 (KM))

A image of the NEO 2016 WJ1 on 2016-12-01
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of  3 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the NEO 2016 WJ1 on 2016-12-01
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of  3 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the NEO 2016 WJ1 on 2016-12-01
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of  3 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the NEO 2016 WJ1 on 2016-12-01
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of  3 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

 Useful Links: 

• Space Situational Awareness(ESA) -- 2016 WJ1
• Near Earth Objects Dynamic Site--2016 WJ1
• (MPC) Observations --2016 WJ1
• JPL Orbit Diagram --2016 WJ1
• NEO Earth Close Approaches (JPL) (up coming)
• JPL's NEO Earth Close-Approaches  (Between 1900 A.D. and 2200 A.D- limited to encounters with  reasonably low uncertainty)
• The Tracking News
• NEO Coordination Centre 
• Speed of Light - Space - Distance Calculator
• Asteroid Hazards: The View from Space(MPC)
• Don’t fear apocalyptic asteroids: you’re safer than you think
• Understanding Risk Pages By Jon Giorgini
• Revised asteroid scale aids understanding of impact risk
• Near Earth Objects Scale Helps Risk Communication
• Dealing With the Impact Hazard: An International Project
• The Palermo Technical Impact Hazard Scale
• An Asteroid as Entered the Blogosphere… Should I Be Worried? A commentary by Steven M. Tilley
• International Asteroid Warning Network 
• Impact Risk Assessment: An Introduction - Near-Earth Object Program
• Hazardous NEO Technical Reviews
• Frequently Asked Questions For Impact Risk Assessment 
• How to Find an Impact Orbit for the Earth-Asteroid Collision
• The Asteroid/Comet Impact Hazard
• Whom should we call? Data policy for immediate impactors announcements
• NEO Search & Follow-Up
• NEOs' Science pages  by Livia Giacomini 
• 
  

The NEO 2016 WJ1 on 2016-11-25 from Siding Spring - Australia

See The NEO 2016 WJ1 Has Been Removed from the Sentry Risk Table--Neodys Risk Table List 3 Possible Impacts 2106-2115.

NOTE with only 6 days data-arc span there is "little" known about the NEO 2016 WJ1 and the information in this post may become outdated. So one should check the links for updates. Whenever an object is posted to one the risk lists (especially if it has a Torino Scale 1 or greater) and it is observable, observers will take a particular interest in it. In the coming days it is possible there will be more follow-up observations and a search in archives for precovery observations. It is likely this object will be removed from the risk lists.

Background
(as of 2016-11-25) 

• Object: 2016 WJ1 
• Approximate Diameter: 140  m - 320  m (459.318 feet to 1049.87 feet)(Absolute Magnitude: H= 21.338)
• Orbit Type: Apollo [NEO]- Potentially Hazardous Asteroid
• On the Sentry Risk Table: yes  NO
•  NOTE this is NOT a prediction of an impact but rather a statement there is insufficient observational data rule out an impact -- for information read  Understanding Risk Pages by Jon Giorgini
•  Torino Scale(JPL): 1 
• "A routine discovery in which a pass near the Earth is predicted that poses no unusual level of danger. Current calculations show the chance of collision is extremely unlikely with no cause for public attention or public concern. New telescopic observations very likely will lead to re-assignment to Level 0"
• On the NEODyS CLOMON2 risk page: yes
• Torino Scale(NEODyS CLOMON2): 1
• First observation was made: 2016 11 19.46522
• First observed by: Mt. Lemmon Survey (MPC Code G96) The Discovery M.P.E.C.: MPEC 2016-W38 : 2016 WJ1
• Last Observation(publish): 2016 11 25.183886 (by OASI, Nova ItacurubaI (MPC Code Y28)
• Data-Arc Span(publish) : 6 days
• Number of Optical Observations(published): 80
• Observatories Reporting (Published) Observations(MPC Code):
• (246) Klet Observatory-KLENOT,Czech Republic. 
• (291) LPL/Spacewatch II,Arizona,US. 
• (691) Steward Observatory, Kitt Peak-Spacewatch, Arizona,US.
• (926) Tenagra II Observatory, Nogales,Arizona, US. 
• (958) Observatoire de Dax, France.
• (G96) Mt. Lemmon Survey, Arizona,US. 
• (H06) iTelescope Observatory, Mayhill,New Mexico,US.
• (H21) Astronomical Research Observatory, Westfield, Illinois,US.
• (I52) Steward Observatory, Mt. Lemmon Station,Arizona,US.
• (K88) GINOP-KHK, Piszkesteto, Hungary.
• (L04) ROASTERR-1 Observatory, Cluj-Napoca, Romania.
• (Q62) iTelescope Observatory, Siding Spring,NSW,Australia. 
• (T12) Mauna Kea-UH/Tholen NEO Follow-U, Hawaii,US.
• (Y28) OASI, Nova Itacuruba, Brazil.
• Perihelion Distance: 0.6643788245227231 (AU)
• Aphelion Distance: 2.019174401968141 (AU)
• Earth MOID: 0.000357041 AU ( 0.139 (LD)) or 33,189.034 miles (53,412.573 (KM))
• Close-Approach to Earth: Will safely pass Earth on 2016-December-16 at a Nominal Distance of  0.05398437711059 (AU) (21.009 (LD)) or 5,018,161.354 miles (8,075,947.866 (KM))

A image of the NEO 2016 WJ1 on 2016-11-25
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the NEO 2016 WJ1 on 2016-11-25
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the NEO 2016 WJ1 on 2016-11-25
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

Useful Links: 

• Space Situational Awareness(ESA) -- 2016 WJ1
• Near Earth Objects Dynamic Site--2016 WJ1
• (MPC) Observations --2016 WJ1
• JPL Orbit Diagram --2016 WJ1
• NEO Earth Close Approaches (JPL) (up coming)
• JPL's NEO Earth Close-Approaches  (Between 1900 A.D. and 2200 A.D- limited to encounters with  reasonably low uncertainty)
• The Tracking News
• NEO Coordination Centre 
• Speed of Light - Space - Distance Calculator
• Asteroid Hazards: The View from Space(MPC)
• Don’t fear apocalyptic asteroids: you’re safer than you think
• Understanding Risk Pages By Jon Giorgini
• Revised asteroid scale aids understanding of impact risk
• Near Earth Objects Scale Helps Risk Communication
• Dealing With the Impact Hazard: An International Project
• The Palermo Technical Impact Hazard Scale
• An Asteroid as Entered the Blogosphere… Should I Be Worried? A commentary by Steven M. Tilley
• International Asteroid Warning Network 
• Impact Risk Assessment: An Introduction - Near-Earth Object Program
• Hazardous NEO Technical Reviews
• Frequently Asked Questions For Impact Risk Assessment 
• How to Find an Impact Orbit for the Earth-Asteroid Collision
• The Asteroid/Comet Impact Hazard
• Whom should we call? Data policy for immediate impactors announcements

The NEO 2016 WJ1 on 2016-11-24 from Siding Spring - Australia

See The NEO 2016 WJ1 Has Been Removed from the Sentry Risk Table--Neodys Risk Table List 3 Possible Impacts 2106-2115.

NOTE with only 4 days data-arc span there is "little" known about the NEO 2016 WJ1 and the information in this post may become outdated. So one should check the links for updates. Whenever an object is posted to one the risk lists (especially if it has a Torino Scale 1 or greater) and it is observable, observers will take a particular interest in it. In the coming days it is possible there will be more follow-up observations and a search in archives for precovery observations. It is likely this object will be removed from the risk lists.

Background
(as of 2016-11-24) 

• Object: 2016 WJ1 
• Approximate Diameter: 140  m - 320  m (459.318 feet to 1049.87 feet)(Absolute Magnitude: H= 21.328)
• Orbit Type: Apollo [NEO]- Potentially Hazardous Asteroid
• On the Sentry Risk Table: yes NO 
•  NOTE this is NOT a prediction of an impact but rather a statement there is insufficient observational data rule out an impact -- for information read  Understanding Risk Pages by Jon Giorgini
•  Torino Scale(JPL): 1 
• "A routine discovery in which a pass near the Earth is predicted that poses no unusual level of danger. Current calculations show the chance of collision is extremely unlikely with no cause for public attention or public concern. New telescopic observations very likely will lead to re-assignment to Level 0"
• On the NEODyS CLOMON2 risk page: yes
• Torino Scale(NEODyS CLOMON2): 1
• First observation was made: 2016 11 19.46522
• First observed by: Mt. Lemmon Survey (MPC Code G96) The Discovery M.P.E.C.: MPEC 2016-W38 : 2016 WJ1
• Last Observation(publish): 2016 11 24.49274 (by LPL/Spacewatch II (MPC Code 291)
• Data-Arc Span(publish) : 5 days
• Number of Optical Observations(published): 68
  
• Perihelion Distance: 0.6646977875617796 (AU)
• Aphelion Distance: 2.016698875781032 (AU)
• Earth MOID: 0.000378886 AU ( 0.147 (LD)) or 35,219.654 miles (56,680.539 (KM))
• Close-Approach to Earth: Will safely pass Earth on 2016-December-16 at a Nominal Distance of  0.0539141743012569 (AU) (20.982 (LD)) or 5,011,635.595 miles (8,065,445.676 (KM))

A image of the NEO 2016 WJ1 on 2016-11-24
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

  

A image of the NEO 2016 WJ1 on 2016-11-24
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 60 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

Useful Links:

• Space Situational Awareness(ESA) -- 2016 WJ1
• Near Earth Objects Dynamic Site--2016 WJ1
• (MPC) Observations --2016 WJ1
• JPL Orbit Diagram --2016 WJ1
• NEO Earth Close Approaches (JPL) (up coming)
• JPL's NEO Earth Close-Approaches  (Between 1900 A.D. and 2200 A.D- limited to encounters with  reasonably low uncertainty)
• The Tracking News
• NEO Coordination Centre 
• Speed of Light - Space - Distance Calculator
• Asteroid Hazards: The View from Space(MPC)
• Don’t fear apocalyptic asteroids: you’re safer than you think
• Understanding Risk Pages By Jon Giorgini
• Revised asteroid scale aids understanding of impact risk
• Near Earth Objects Scale Helps Risk Communication
• Dealing With the Impact Hazard: An International Project
• The Palermo Technical Impact Hazard Scale
• An Asteroid as Entered the Blogosphere… Should I Be Worried? A commentary by Steven M. Tilley
• International Asteroid Warning Network 
• Impact Risk Assessment: An Introduction - Near-Earth Object Program
• Hazardous NEO Technical Reviews
• Frequently Asked Questions For Impact Risk Assessment 
• How to Find an Impact Orbit for the Earth-Asteroid Collision
• The Asteroid/Comet Impact Hazard
• Whom should we call? Data policy for immediate impactors announcements

Images of The Asteroid 2016 UG on 2016-11-15 and 2016-11-16

Asteroid(and comet) observing is done by taking a series of images of a section of the night sky over a period of time with a telescope and CCD. Then data reduction is performed on the images looking for moving objects. The observer needs to make two or more observation for each moving object. All “known” objects have a designation, if the observer knows the object’s designation the observation can be reported using the object's designation. If the observer is not trying to identify objects, it is an unknown object or if there is any doubt, an observer-assigned temporary designation is used. The Minor Planet Center’s(MPC) computers check to see if any observations reported  with an observer-assigned temporary designation matchs a “known” objects,  If  any are  "unknown" and its "NEO score is 65” it is posted to “The NEOConfirmation Page”(NEOCP). 

Many observers watch the NEOCP and do follow-up observation on listed objects.   As more observational data comes in better orbital elements can be generated, the "unknown" object may be shown to be a "known" object or shown to be a "new" object. When there are enough observations to generate useful orbital elements the object is assigned a provisional designation by the Minor Planet Center if the object is a NEO, a comet, or unusual a Minor Planet Electronic Circular will be issued.  It is possible over time with additional observational data two or more provisional designations maybe link showing they are the same object.   After four well-observed oppositions for main-belt (two to three for NEOs), asteroids are given a  number ( or their permanent designation and they are eligible to be named by the discoverer).

While many observers will targete NEOs for follow-up observations however other asteroids( i.e., Mars-crossers, main-belt, etc.) may be neglected and over time may become "lost."  On 2016-10-19  a new object was found by Pan-STARRS 1, it was posted to the NEOCP.  Three more observatories submitted observations, and on 2016-10-20.92 it was shown to be a Mars-crossing asteroid and the MPC assigned it the provisional designation 2016 UG.  Since it was not a NEO and pose no danger to Earth, no one targeted it for any follow-up observations.  Then on 2016-11-14 Pan-STARRS 1 reported observations for an object under an observer-assigned temporary designation and it was posted to the NEOCP.  Then observations were reported from two more observatories(including myself), and on 2016-11-16.06 the  "new" NEOCP object was shown to be the Mars-crossing asteroid, 2016 UG  and the orbital elements were updated.

Observations Made Before  the  Object  Was Updates.

A image of the asteroid 2016 UG on 2016-11-15
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 120 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the asteroid 2016 UG on 2016-11-15
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 120 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the asteroid 2016 UG on 2016-11-15
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 5 - 120 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

A image of the asteroid 2016 UG on 2016-11-15
from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
a stack of 15 - 120 second luminance BIN2 images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD)
(C) Steven M. Tilley

Observations Made After  the  Object  Was Updates.

A image of the asteroid 2016 UG on 2016-11-16

 from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)

 a stack of 5 - 120 second luminance BIN2 images taken with iTelescope.net's 

(TEL T27 0.70-m f/6.6 reflector + CCD)

 (C) Steven M. Tilley

A image of the asteroid 2016 UG on 2016-11-16
 from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
 a stack of 5 - 120 second luminance BIN2 images taken with iTelescope.net's 
(TEL T27 0.70-m f/6.6 reflector + CCD)
 (C) Steven M. Tilley

A image of the asteroid 2016 UG on 2016-11-16
 from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
 a stack of 15 - 120 second luminance BIN2 images taken with iTelescope.net's 
(TEL T27 0.70-m f/6.6 reflector + CCD)
 (C) Steven M. Tilley

Background 

(as of 2016-11-17)

• Object: 2016 UG
• Approximate Diameter: 1 km - 2 km (0.621371 miles to 1.24274 miles) (Absolute Magnitude: H= 17.683)
• Orbit Type: Mars-crossing Asteroid
• First Observation was made: 2016 10 19.51822
• First Observed By: Pan-STARRS 1 (MPC Code F51)
• MPECs
• MPEC 2016-U29 : DAILY ORBIT UPDATE (2016 OCT. 21 UT) 
• MPEC 2016-W01 : DAILY ORBIT UPDATE (2016 NOV. 16 UT)
• MPEC 2016-W03 : DAILY ORBIT UPDATE (2016 NOV. 17 UT)
• Data-Arc Span: 28 days

Other links:

• (MPC) Observations 2016 UG 
• JPL Orbit Diagram 2016 BE 
• Guide to Minor Body Astrometry (MPC)
•  Practical guide on how to observe NEOCP object  by Birtwhistle et al.

Confirmation Images of the Asteroid 2016 UZ106

 Background

(as of 2016-11-04)

• Object: 2016 UZ106 
• Approximate Diameter: 1 km - 2 km  (688.976  feet to 1541.99 feet)(Absolute Magnitude:  H= 17.5 )
• Orbit Type:  Inner Main-belt Asteroid [Hungaria]

A confirmation image of the hungaria asteroid 2016 UZ106  

on the night of 2016-11-02 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89) 

using itelescope.net's (t18 TEL 0.32-m f/8.0 reflector + CCD) 

a stack of 7 - 60 Second Luminance BIN2 Images 

(C) Steven M. Tilley

A confirmation image of the hungaria asteroid 2016 UZ106  
on the night of 2016-11-02 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89) 
using itelescope.net's (t18 TEL 0.32-m f/8.0 reflector + CCD) 
a stack of 7 - 60 Second Luminance BIN2 Images 
(C) Steven M. Tilley

A confirmation image of the hungaria asteroid 2016 UZ106  
on the night of 2016-11-02 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89) 
using itelescope.net's (t18 TEL 0.32-m f/8.0 reflector + CCD) 
a stack of 7 - 60 Second Luminance BIN2 Images 
(C) Steven M. Tilley

A confirmation image of the hungaria asteroid 2016 UZ106  
on the night of 2016-11-02 from AstroCamp Observatory. Nerpio, Spain - (MPC Code I89) 
using itelescope.net's (t18 TEL 0.32-m f/8.0 reflector + CCD) 
a stack of 21 - 60 Second Luminance BIN2 Images 
(C) Steven M. Tilley

A confirmation image of the hungaria asteroid 2016 UZ106  

on the night of 2016-11-03 from from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)

using itelescope.net's (T32 TEL 0.43-m f/6.8 reflector + CCD)

 a stack of 10 - 60 Second Luminance BIN2 Images 

(C) Steven M. Tilley

A confirmation image of the hungaria asteroid 2016 UZ106  
on the night of 2016-11-03 from from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
using itelescope.net's (T32 TEL 0.43-m f/6.8 reflector + CCD)
 a stack of 10 - 60 Second Luminance BIN2 Images 
(C) Steven M. Tilley

A confirmation image of the hungaria asteroid 2016 UZ106  
on the night of 2016-11-03 from from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
using itelescope.net's (T32 TEL 0.43-m f/6.8 reflector + CCD)
 a stack of 10 - 60 Second Luminance BIN2 Images 
(C) Steven M. Tilley

Other links:

• (MPC) Observations 2016 UZ106  
• JPL Orbit Diagram 2016 UZ106  
• The NEO Confirmation Page(MPC) 
•  Practical guide on how to observe NEOCP object  by Birtwhistle et al.
• Asteroid-Meteorite Connections in the Hungaria Background Population
• Spratt, Christopher E. (April 1990). "The Hungaria group of minor planets". Journal of the Royal Astronomical Society of Canada. 84 (2): 123–131. Bibcode:1990JRASC..84..123S

A Confirmation Image of The NEO 2016 UE On 2016-10-20

A confirmation image of the Near-Earth Object 2016 UE
on 2016-10-20 from Siding Spring Observatory, Coonabarabran, NSW, Australia. (MPC Q62)
 a stack of 4 - 60 Second Luminance BIN2 Images taken with iTelescope.net's
(TEL T27 0.70-m f/6.6 reflector + CCD) (C) Steven M. Tilley



See:

• MPEC 2016-U25 : 2016 UE
• JPL Orbit Diagram 2016 UE 

Confirmation of the Near-Earth Object 2016 TJ17

Confirmation image of the Near-Earth Object 2016 TJ17 (absolute magnitude =25.4 ~28m) 
on 2016-10-08 a stack of 9-60 second luminance BIN2 taken 
with iTelescope.net's (T17 TEL 0.43-m f/6.8 reflector + CCD) 
at Observatory: Siding Spring - Australia (MPC code Q62)
By Steven M. Tilley

 

 Background

(as of 2016-10-09)

•  Object:  2016 TJ17
• Approximate Diameter: 22 m - 160.761 m(72.1785 feet to 1541.99 feet)( Absolute Magnitude:  H= 25.409 )
• Orbit Type: Apollo [NEO]
• On the Sentry Risk Table:  No  (Never has been listed )
• On the NEODyS CLOMON2 risk page: No 
• First Observed was made on: 2016 10 06.27431
• First Observed  By: Catalina Sky Survey, Arizona,USA (MPC Code 703) The Discovery M.P.E.C.: MPEC 2016-T82 : 2016 TJ17 see The Tracking News(Saturday, 8 October 2016) 
• Last Observed(publish):2016 10 09.26048
• Data-Arc Span(publish) : 3 days
  
•  Number of Observations(publish): 58
• Perihelion Distance:  0.7816366260606531
• Aphelion Distance: 3.537812747373569
• Earth MOID:   0.00117955(0.459 (LD)) 109,646.022 or miles (176,458.168 (KM))
• Last Close-Approach to Earth:  Passed the Earth on  at a Nominal Distance of 0.0031372716407202  (AU), (1.221Lunar Distance (LD)), or 291,627.618 miles ( 469,329.157(KM))

    Other links:

• Space Situational Awareness(ESA)  2016 TJ17
• Near Earth Objects Dynamic Site--2016 TJ17
• (MPC) Observations 2016 TJ17 
• JPL Orbit Diagram 2009 ES 
• NEO Earth Close Approaches (JPL)
• The Tracking News 
• NEO Coordination Centre 
• Speed of Light - Space - Distance Calculator
• Asteroid Hazards: The View from Space(MPC) 
• Understanding Risk Pages By Jon Giorgini
•  An Asteroid as Entered the Blogosphere… Should I Be Worried? A commentary by Steven M. Tilley
•  Don’t fear apocalyptic asteroids: you’re safer than you think 
• The NEO Confirmation Page(MPC) 
•  Practical guide on how to observe NEOCP object  by Birtwhistle et al.