Synthetic Solar System Model(S3M) MOPS Workshop

Tucson, March 11th 2008Tommy Grav

ContributorsTommy GravRobert JedickeSteve ChesleyMatthew HolmanTim SpahrLarry Denneau

What is S3M?Tool to help:

Test the MOPS pipelineCan we detect, link and track all types of objects?

Even the special types, like interstellar comets

Can we handle the density of objects expected?

Provide efficiency determination of system

Compare PS1/PS4/LSST results to “theory”

S3M RequirementsDe-biased populationsUp to date models if availableAppropriate densitiesComplete to V~24.5

Where does S3M fit in?

Field Detections

S3M

Processing

Inner Solar System

Inner Solar SystemNear Earth Objects

Includes Inner Earth ObjectsEarth Impactors

Main Belt AsteroidsJovian TrojansShort Period Comets

Outer Solar System

Outer Solar SystemCentaursTrans-Neptunian Objects

Classical Kuiper BeltResonant population, incl neptunian trojans

Scattered Disk ObjectsLong Period CometInterstellar comets

What is the S3M? ~11,000,000 objects with:

Orbital elementsPerihelion distanceEccentricityInclinationArgument of perihelionLongitude of ascending nodeTime of perihelion passage

Absolute magnitude Each population is built using its own set of assumptions and techniques

Near-Earth Objects

Near-Earth ObjectsModel based on Bottke et al. (2002)

Time-residence model

Earth Impactors Made by S. Chesley

Subset of the NEOs

10M NEOs ->10006 obj

Impact from 2010-2100 Twice per week

Earth Impactors

Main Belt Asteroids

Known Synthetic

Main Belt Asteroids

Bright Known

All Known

Main Belt Asteroids

Want to retain the important featuresKirkwood gapsFamily structure

Known sample of MBAs is biased but bright portion (H < 14.5) is complete

Use bright sample to build our MBA modelTake known MBA shift (a,e,i), random angles

This “smears” out gaps and familiesHilda structure is lost

Main Belt Asteroids

Jovian Trojans

Jovian Trojans Based on SDSS data

Integrated clone orbits

Removed non-stable

Make sure objects are 1:1 resonant

Jovian Trojans

Trojans of Other Planets

All planets 10000

Mercury Venus Earth Mars

20000 Saturn Uranus Neptune

TNO model has some neptunian trojans

Centaurs

Centuars Based on

Jedicke et al (1997)

Duncan et al (1995)

Time residence model

Trans-Neptunian Objects

Trans-Neptunian Objects

Based on Nice Model Morbidelli & Levison

Integration of orbits Picking clone orbits Divide population into 3 sub-populations Classical Kuiper belt objects Resonant Kuiper belt objects

From the 1:1 to the 3:1 mean motion resonance Scattered disk objects

Average a > 48AU

Trans-Neptunian Objects

Scattered Disk Objects

Average a > 48AU Does not include Sedna-like objects

Scattered Disk Objects

Long Period Comets Based on Franics (2005)

LINEAR data Close to parabolic

a > 1000AU Inclination isotropic

Interstellar comets

Eccentricity > 1 Isotropic inclination

Use no known to determine upper limit density

Grid PopulationProvide the possible unknown populationsDistant circular objectsRetrograde objectsHigh inclination objects

Test limits of pipeline

Grid PopulationRandom positions and velocitiesInside a sphere of 5000AUEccentricities e < 1.Absolute magnitude to ensure observability

In progress

S3M SummaryKnown PS1 PS4 S3M

Near Earth Objects ~5,000 ~5,000 ~25,000 268,896

Earth Impactors 0 Unknown Unknown 10,006

Main Belt Asteroids ~300,000 ~1,000,000 ~10,000,000 10,000,000

Jovian Trojans ~2,000 ~20,000 ~100,000 280,000

Centaurs ~50 ~300 ~1000

Classical KBOs ~1000 ~3000 ~10,000 42,709

Resonant KBOs 6,142

Neptunian Trojans 6 ~50 ~200 20,000

Scattered Disk Objects

~100 ~500 ~2000 10,952

Jupiter Family Comets

~350 ~500 ~5000 TBD

Long Period Comets ~1000 ~1000 ~9400 9,400

Interstellar Comets 0 unknown unknown 8,300

Current Shortcomings

Somewhat MOPS specificEasily corrected

Missing populationsShort period comets (JFCs and HFC)

Work underway by Grav & Spahr

Distant TNOs

No physical properties beyond HSome models might need updating

Improvement Priorities

Short period comets Un-MOPSing the models Adding properties to calculate thermal flux Means addition of some software to the model

Extending to fainter apparent magnitude Adding phase integral values Adding spectral gradient for color variations

Updating population models

Future of S3MLSSTWISE tests of MOPSAsteroid contamination of space missions

Other surveys (both planning/operations)