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only 4 days data-arc span there is "little" known about the NEO 2016 WJ1 and the information in this post may become outdated.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