690 likes | 867 Views
The Pan-STARRS M oving O bject P rocessing S ystem (& Science). Robert Jedicke (for the Pan-STARRS collaboration) Institute for Astronomy University of Hawaii 2004 September 29. IMPACT. I. M. P. A. C. T. IMPACT. Natural.
E N D
The Pan-STARRSMoving Object Processing System(& Science) Robert Jedicke (for the Pan-STARRS collaboration) Institute for Astronomy University of Hawaii 2004 September 29
IMPACT I M P A C T
Natural The Pan-STARRSMoving Object Processing System(& Science) Robert Jedicke (for the Pan-STARRS collaboration) Institute for Astronomy University of Hawaii 2004 September 16
The Pan-STARRSMoving Object Processing System(& Science) (& Science) Robert Jedicke (for the Pan-STARRS collaboration) Institute for Astronomy University of Hawaii 2004 September 16
Asteroids are just like satellites but... Bigger Further Slower Dumber
BIGGER Bigger Further Slower Dumber FURTHER SLOWER DUMBER
DEFINITIONS icier COMETS ASTEROIDS dirtier
DEFINITIONS Near Earth Objects (NEO) NEO ZONEPerihelion < 1.3AU(about 130 million miles)
DEFINITIONS Potentially Hazardous Objects (PHO) PHO ZONEMOID < 0.05 AU(about 5 million miles)
PHO Orbit Earth Collisionat perihelion
Non-Collision ‘PHO’ Orbit Not at Earth’sorbit at perihelion
DEFINITIONS Death Plunge Objects (DPO)* * Not an official acronym
Solar System Animation #3 Planetary Pinball !
DEFINITIONS Trojans Main Belt Objects Trojans
Short PeriodComets DEFINITIONS Centaurs Trans-Neptunian Objects (TNO) Comets HalleyFamilyComets Long Period Comets
DEFINITIONS 3 light years Oort Cloud
Selected PanSTARRS’s TopLevel Science Requirements • MOPS shall create and maintain a data collection of detections and object parameters (e.g. orbit elements, absolute magnitudes) for >90\% of the PHOs that reach R=24 for 12 contiguous days during the course of Pan-STARRS operations. • MOPS shall create and maintain a data collection (DC) of detections and object parameters (e.g. orbit elements, absolute magnitudes) for >90% of the members that reach R=24 12 contiguous days within each class of solar system object (Main Belt, Trojan, Centaur, TNO, Comet, etc, except NEO and PHO) during the course of Pan-STARRS operations.
Selected PanSTARRS’s TopLevel Science Requirements Find lots of • MOPS shall create and maintain a data collection of detections and object parameters (e.g. orbit elements, absolute magnitudes) for >90\% of the PHOs that reach R=24 for 12 contiguous days during the course of Pan-STARRS operations. • MOPS shall create and maintain a data collection (DC) of detections and object parameters (e.g. orbit elements, absolute magnitudes) for >90% of the members that reach R=24 12 contiguous days within each class of solar system object (Main Belt, Trojan, Centaur, TNO, Comet, etc, except NEO and PHO) during the course of Pan-STARRS operations. Asteroids and Comets
Why? WHY?
REASON #1 1 in 2000 chance of major impact this century.
REASON #2 Congress said to.
SPACEGUARD GOAL In 1994 the US Congress recommended that, to the extent practicable, NASA shall identify within 10 years the NEOs that are >1km diameter that cross Earth's orbit.
SPACEGUARD GOAL In 1998 NASA committed to detecting 90% of NEOs >1 km diameter within 10 years.
NASA NEO SDT In 2003 NASA's NEO Science Definition Team recommend extending 90% completeness to about the 250m level.
Pan-STARRS & PHOs • 99% completion of PHOs with D>1km • 90% reduction in residualglobal impact risk • 90% completion of PHOs with D>300m • 50% reduction in sub-global impact risk • 99% completion of PHOs with D>1km • 90% reduction in residualglobal impact risk • 90% completion of PHOs with D>300m • 50% reduction in sub-global impact risk
REASON #3 Science Opportunities
REASON #4 Better Surf Forecasts
Existing Surveys Existing Surveys
LINEARWhite Sands, NM) LONEOSFlagstaff, AZ NEAT/JPLHaleakala, Maui NEAT/JPLPalomar, CA CSS -SouthAustralia CSS - NorthMt. Lemmon, AZ SpacewatchKitt Peak, AZ UHAS Mauna Kea, HI Existing Surveys – Step 1:Discovery & Identification • 3-5 images/night • Linear motion • Very low false-positive rate • 3-5 images/night • Linear motion • Very low false-positive rate
Existing Surveys – Step 2Linkage & Orbit Determination • Links detections to known objects • Identifies new objects • Fits orbits to all objects with new detections • Much more… • Links detections to known objects • Identifies new objects • Fits orbits to all objects with new detections • Much more… MPC
Existing Surveys – Step 3Impact Risk Assessment • Refine orbits • Calculate impact probability • Refine orbits • Calculate impact probability
Moving Object Processing System Pan-STARRS Telescopes &Survey ImageProcessingPipeline MOPS ImpactProbability • Fully integrated • Detection, attribution, linking,orbit identification • Orbit fitting • Parallel synthetic data analysis • Real-time efficiency/bias • Fully integrated • Detection, attribution, linking,orbit identification • Orbit fitting • Parallel synthetic data analysis • Real-time efficiency/bias
Moving Object Processing System WHY NOT USE MPC?
Moving Object Processing System • MPC requires that reported detections be real • forces Pan-STARRS to obtain 3 images/night • reducing total sky coverage • reducing total discoveries • Difficult to control/monitor system efficiency • introduce synthetic objects into data stream • determine efficiency in real time • monitor system performance in real time • MPC requires that reported detections be real • forces Pan-STARRS to obtain 3 images/night • reducing total sky coverage • reducing total discoveries • Difficult to control/monitor system efficiency • introduce synthetic objects into data stream • determine efficiency in real time • monitor system performance in real time
PanSTARRS Asteroid Surveying • 107 asteroids within range of PanSTARRS • ~200/ deg2 @ V=24 @ on ecliptic • 107 detections / month (20X current rates) • 107 asteroids within range of PanSTARRS • ~200/ deg2 @ V=24 @ on ecliptic • 107 detections / month (20X current rates)
Cumulative Observations PS1 Starts
Observing Cadence • Every survey mode obtains at least twoimages at each location separated by a Transient Time Interval (15-30 minutes) • serendipitous positions & colours • Solar system survey re-visits each location after 3-6 days • obtain 3-4 nights/month • ~12 day arc • Every survey mode obtains at least twoimages at each location separated by a Transient Time Interval (15-30 minutes) • serendipitous positions & colours • Solar system survey re-visits each location after 3-6 days • obtain 3-4 nights/month • ~12 day arc
Moving Object Processing System • 2 detections/nightwith multi-night linking • 2 detections/nightwith multi-night linking • increased sky coverage • push deeper into noise • more objects • increased sky coverage • push deeper into noise • more objects • synthetic data • synthetic data • real-time system monitoring • efficiency determination • correction for selection effects • real-time system monitoring • efficiency determination • correction for selection effects
Stationary Combined Static Transients Moving Transient Detection (IPP) 4 Telescopes + + +
Transient Types Supernovae/GRB Cometary Object Slow Asteroidal Object Difference Death Plunge Object Normal Asteroidal Object Fast Asteroidal Object
Linking Detections Day 11 Field-of-view1500 real detections +1500 false detections
Linking Detections Day 51 Field-of-view1500 real detections +1500 false detections
Linking Detections Day 91 Field-of-view1500 real detections +1500 false detections
Linking Detections • Brute force (MPC) approach • 100X Pan-STARRS computing power • kd-tree (CMU) approach • ~1/3 Pan-STARRS computer power • Brute force (MPC) approach • 100X Pan-STARRS computing power • kd-tree (CMU) approach • ~1/3 Pan-STARRS computer power
Orbit Determination • Must include • All major solar system perturbing bodies • Full error analysis • Two available solutions • AstDys (Italy) • JPL (USA) • Must include • All major solar system perturbing bodies • Full error analysis • Two available solutions • AstDys (Italy) • JPL (USA)
Data Storage • Large by most astronomical standards • Small in comparison to Pan-STARRS (~1%) 500 TerraBytes