Moving Object Pipeline Requirements

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Moving Object PipelineRequirements

• Internal Preliminary
• Requirements Review
• 2003-08-06
• Robert Jedicke

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Outline

• Background
• Requirements
• Selected Derived Requirements
• Crazy Random Thoughts

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MBO Sky-Plane Distribution
Main Belt Objects
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PHO Sky-Plane Distribution - Sunset
Potentially Hazardous Objects End of Twilight Ton
ight
Sunset
Midnight
Sunrise
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PHO Sky-Plane Distribution - Midnight
Potentially Hazardous Objects Midnight Tonight
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PHO Sky-Plane Distribution - Sunrise
Potentially Hazardous Objects Start of Twilight T
omorrow Morning
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MO Sky-Plane Density

• 107 asteroids with V
• 200/deg2 along ecliptic incl. sweet spots
• 300/deg2 _at_ oppn.
• 100/deg2 w/ lopp

300,000 MO/night!
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Unit Exposure Time (UET)

• All images acquired in a filter and sky dependent
  Unit Exposure Time
  
• Longer exposures built up by combining multiple
  Unit Exposure images
  
• E.g. 30s in solar system filter

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Transient Time Interval (TTI)

• Exposures built up of ? 2 Unit Exposures
  separated by a Transient Time Interval
  
• Allows separation of stationary and
  non-stationary transients
  
• 15-30 minutes? Position dependent.
• Need to balance detection of Moving Objects
  against (e.g.) GRB detection delays against
  weather

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Transient Ubiquity

• ? (almost?) all observing modes contribute to
  detection of transient stationary and moving
  objects.

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Background Noise

• 200 false 5-sigma transients / deg2
• About the same density as real moving objects on
  the ecliptic
  
• 200,000 3-sigma detections / deg2

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T0 image 200 real 200 false
T 0 min
1 deg2
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T0 image 200 real 200 false
T 15 min
1 deg2
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T0 image 200 real 200 false
Superimposed
1 deg2
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Moving Object Pipeline Schematic
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Moving Object Pipeline Requirements

• Identify moving objects in the non-stationary
  transient catalog and, when possible, link
  observations of the same objects together and
  determine their orbits
• Identify objects which pose a collision hazard
  with Earth and then determine the risk of impact.

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Moving Object Pipeline Requirements

• Make all moving object catalogs, orbits and
  impact risk assessments available to the
  international community as soon as possible.
  
• Must be capable of self-monitoring performance
  and provide useful feedback to the user.

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Derived Requirement 1
(Requirement 1)

• Inputs
• Observation Time (e.g. UT, JD)
• Centroid position (RA, DEC) coordinate system
  (e.g. J2000, B1950)
  
• Magnitude, S/N
• Filter (e.g. V, R)
• Ellipticity, orientation, etc
• Error estimates for all values

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Derived Requirement 2
(Requirement 1)

• Designating
• Unique assignment of identifier to each probable
  Moving Object
  
• Unique assignment of identifier to orbits of
  linked observations

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Derived Requirement 3
(Requirement 1)

• Linking Long-Arc Orbits to Observations
• Must be able to link new observations of
  previously observed objects with earlier good
  orbit determined for that object if it exists

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Derived Requirement 4
(Requirement 1)

• Linking Short-Arc Orbits to Observations
• Must be able to link new observations of
  previously observed objects with earlier weakly
  determined orbit for that object if it exists

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Derived Requirement 5
(Requirement 1)

• Linking intra-lunation observations
• Observations of the same object within a lunation
  which do not link to long or short arc should be
  linked to each other.

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Derived Requirement 6
(Requirement 1)

• Linking Short-Arc Orbits to Short-Arc Orbits
• Short-arc orbits identified in one lunation may
  be linked to short-arc orbits found in other
  lunations

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Derived Requirement 7
(Requirement 1)

• Linking Long-Arc Orbits to the Transient Object
  Database
  
• Once an orbit is well-established you can mine
  the 3-sigma non-stationary transient detection
  database for pre-coveries of the object to
  further improve the orbit.

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Derived Requirement 8
(Requirement 2)

• Potentially Hazardous Object Risk Analysis and
  Warnings
  
• About 2 (50/2400) of NEOs currently have
  non-zero collision probability.
  
• PanSTARRS aims to reach 90 completion of all
  NEOs to about 200-300m diameter (15,000)
  
• PanSTARRS will detect many smaller objects as
  well so we assume a total of 30K NEOs
  
• ? over the lifetime of the project there may be
  about 600 Potential Impactors at any time.

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Derived Requirement 9
(Requirement 3)

• Distribution of Orbits, Observations and Risk
  Analysis to the Worldwide Community
  
• In nearly real time

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Derived Requirement 10
(Requirement 4)

• Performance Monitoring
• To quantify, monitor and test performance of the
  moving object pipeline
  
• E.g. perhaps maintain a database of 107 fake but
  realistic objects (NEO, MBO, KBO) which are
  injected into the pipeline at some TBD point.

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Derived Requirement 11a
(Requirement 3)

• Output
• Observation Database(s)
• 3-sigma non-stationary unlinked detections
• 5-sigma unlinked detections
• Linked detections
• High-probability observations of objects with
  well-determined orbits
  
• Lower-probability observations of objects with
  only short-arc orbits
  

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Derived Requirement 11b
(Requirement 3)

• Output
• Orbit Database(s)
• High quality long-arc orbits
• Low quality short-arc orbits

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Crazy Random Thoughts

• Chesley has estimated that implementing a MO
  Pipeline would require 5-10 person-years based on
  experience at AstDys and JPL.
  
• Minor Planet Center currently employs 3 people to
  monitor/maintain
  

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Crazy Random Thoughts

• Much of the Moving Object Pipeline is already
  performed at the Minor Planet Center (MPC)
  
• MPC currently handles 20,000 objects/day
• Spahr (MPC) says they could handle 2-3? the data
  rate with some difficulty
  
• THEY ARE WITHIN A FACTOR OF 10!

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Crazy Random Thoughts

• JPL (Yeomans), Lowell (Bowell) and AstDys
  (Milani) already handle many parts of the Moving
  Object Pipeline
  
• None of them (including MPC) are fully automated.
  They still require human intervention in their
  procedures. This is not acceptable for
  PanSTARRSs data rate.

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Crazy Random Thoughts

• Do we want to become the MPC?
• What parts do we need to implement?
• Team Asteroid meets tomorrow to (politely)
  discuss many of these issues.

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The End
THE END