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The Small Telescope Science The Small Telescope Science ProgramProgram

Deep Impact MissionDeep Impact Mission

Stephanie McLaughlin (Univ. of Maryland)Stephanie McLaughlin (Univ. of Maryland)

Lucy McFadden (Univ. of Maryland)Lucy McFadden (Univ. of Maryland)

Gary Emerson (Ball Aerospace & Technologies)Gary Emerson (Ball Aerospace & Technologies)

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An Overview of Deep ImpactAn Overview of Deep Impact

• Fundamental scientific objective: Fundamental scientific objective: probe beneath a cometary surfaceprobe beneath a cometary surface

• Two-component spacecraft: Two-component spacecraft: Flyby spacecraft and auto-guided, Flyby spacecraft and auto-guided, imaging impactorimaging impactor

• Launch in December 2004Launch in December 2004

• Impact with comet 9P/Tempel 1 on Impact with comet 9P/Tempel 1 on July 4, 2005 will form ~100m craterJuly 4, 2005 will form ~100m crater

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Ground-based ObservationsGround-based Observations

• Science team is conducting a vigorous Science team is conducting a vigorous program of ground-based observations:program of ground-based observations:

– Volatile outgassingVolatile outgassing

– Dust coma developmentDust coma development

– Jet activity and outburstsJet activity and outbursts

• Goal: Establish baselines of Tempel 1’s Goal: Establish baselines of Tempel 1’s activity for comparison to impact and activity for comparison to impact and post-impact observationspost-impact observations

• However, few observations of Tempel 1:However, few observations of Tempel 1:

– Discovered in 1867 but lost from Discovered in 1867 but lost from 1869 to 19721869 to 1972

– Rather dim, 9th magnitudeRather dim, 9th magnitude

• And, time on large telescopes is And, time on large telescopes is limited...limited...

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Small Telescopes to the RescueSmall Telescopes to the Rescue

• Advanced amateurs and private observatories can provide Advanced amateurs and private observatories can provide good temporal coverage to supplement sparse baselinesgood temporal coverage to supplement sparse baselines

• Typically have:Typically have:

– Fast, wide-field telescopesFast, wide-field telescopes

– High-quality, commercial CCD camerasHigh-quality, commercial CCD cameras

– UBVRI filtersUBVRI filters

• Combination good for:Combination good for:

– Imaging and photometry of dust coma (RI)Imaging and photometry of dust coma (RI)

– Imaging of jet activity and outbursts? (VRI)Imaging of jet activity and outbursts? (VRI)

• Hence, the STSP...Hence, the STSP...

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2000-08-26.1 UT, 1x180s, R Filter

Wendelstein Observatory, M. Tschimmel

The Small Telescope Science The Small Telescope Science ProgramProgram

• The STSP is an E/PO project for the The STSP is an E/PO project for the missionmission

• Originator: Gary EmersonOriginator: Gary Emerson

• Campaign in 2000, very successful: Campaign in 2000, very successful:

– Network of 40+ observers in 12 Network of 40+ observers in 12 countries, spanning 6 continentscountries, spanning 6 continents

– Observers acquired 700+ VRI and Observers acquired 700+ VRI and 300+ unfiltered CCD images300+ unfiltered CCD images

• Program in hibernation for past 3 Program in hibernation for past 3 years, except for:years, except for:

– DS/1, LINEAR C/2000 W1, StardustDS/1, LINEAR C/2000 W1, Stardust

• Re-launches this fallRe-launches this fall

• Continues through 2005Continues through 2005

2000-08-06.3 UT

The George Observatory, Fort Bend Astro. Club

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STSP: Filling the GapsSTSP: Filling the Gaps

• Northern Obs: Northern Obs: Oct ‘04 - Aug ‘05Oct ‘04 - Aug ‘05

• Southern Obs: Southern Obs: Feb - Dec ‘05Feb - Dec ‘05

• STSP contributionsSTSP contributions

• Dust production Dust production light curve:light curve:

Large telescope Large telescope contributionscontributions

ImpactImpact

• Impact:Impact: One day One day before perihelionbefore perihelion

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Jet Activity and Outbursts?Jet Activity and Outbursts?

• Evidence for jet activity during 1983 Evidence for jet activity during 1983 apparitionapparition

– Upper: 3 months pre-perihelionUpper: 3 months pre-perihelion

– Lower: 1 month pre-perihelionLower: 1 month pre-perihelion

• Expect jet activity 3-4 months before Expect jet activity 3-4 months before perihelion, Mar - Jun 2005perihelion, Mar - Jun 2005

• Not sure if comet has outbursts; Not sure if comet has outbursts; continuous imaging over the next year is continuous imaging over the next year is neededneeded

• Impact is expected to make a new active Impact is expected to make a new active area: Jets or outbursts days or weeks area: Jets or outbursts days or weeks after impact? after impact?

• STSP observers can help monitor for pre- STSP observers can help monitor for pre- and post-impact activityand post-impact activityJean-Claude Merlin (ICQ 1983)

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What We’re Looking for...What We’re Looking for...

• Advanced amateur observers with discretionary telescope time Advanced amateur observers with discretionary telescope time

• Fast, wide-field telescope systems; CCDs; VRI filtersFast, wide-field telescope systems; CCDs; VRI filters

• Aperture photometry (RI): Oct 2004 - Dec 2005Aperture photometry (RI): Oct 2004 - Dec 2005

• VRI imaging for jet activity, outbursts: Mar - Sep 2005VRI imaging for jet activity, outbursts: Mar - Sep 2005

• Narrowband images and spectroscopy also acceptedNarrowband images and spectroscopy also accepted

• Interested?Interested? Please contact us after the Pro-Am Session! Please contact us after the Pro-Am Session!

Stef McLaughlin (stefmcl@astro.umd.edu)Stef McLaughlin (stefmcl@astro.umd.edu)Gary Emerson (emerson@ball.com)Gary Emerson (emerson@ball.com)

or visit the STSP website:or visit the STSP website:

http://deepimpact.astrohttp://deepimpact.astro ..umd.edu/umd.edu/stspstsp

• Reference: The NASA Deep Impact Mission’s Small Telescope Science Program in the Future Reference: The NASA Deep Impact Mission’s Small Telescope Science Program in the Future of Small Telescopes in the New Millenium, Astro. & Sp. Sci. Library, Ed. Terry Oswalt, Vol. 289, of Small Telescopes in the New Millenium, Astro. & Sp. Sci. Library, Ed. Terry Oswalt, Vol. 289, Kluwer Academic Publishers, 2003, p. 57.Kluwer Academic Publishers, 2003, p. 57.

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Backup SlidesBackup Slides

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Scientific ObjectivesScientific Objectives

• Primary Scientific ThemePrimary Scientific Theme

– Understand the differences between interior and Understand the differences between interior and surfacesurface

– Determine basic cometary properties (density, Determine basic cometary properties (density, porosity, etc.)porosity, etc.)

– Search for pristine material below surfaceSearch for pristine material below surface

• Secondary Scientific ThemeSecondary Scientific Theme

– Distinguish extinction from dormancyDistinguish extinction from dormancy

• Additional Science AddressedAdditional Science Addressed

– Address terrestrial hazard from cometary impactsAddress terrestrial hazard from cometary impacts

– Search for heterogeneity at scale of cometesimalsSearch for heterogeneity at scale of cometesimals

– Calibrate the cratering recordCalibrate the cratering record

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Inter-Planetary TrajectoryInter-Planetary Trajectory

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Encounter SchematicEncounter Schematic

Tempel 1Nucleus

Shield ModeAttitude through

Inner Coma

Science and Autonav Imaging toImpact + 800 sec

ITM-1 E-88 min

ITM-2E-48 min

ITM-3E-15 min

Impactor ReleaseE-24 hours

AutoNav EnabledE-2 hr

Flyby S/CDeflection Maneuver

E-23.5 hr

2-wayS-band

Crosslink

500 km

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9P/Tempel 19P/Tempel 1

• History:History:

– April 1867 discoveredApril 1867 discovered

– 1873, 1879 observed1873, 1879 observed

– 1881 close approach to Jupiter, then lost1881 close approach to Jupiter, then lost

– 1967 Recovered1967 Recovered

• Jupiter familyJupiter family

• Orbital period = 5.5 yearsOrbital period = 5.5 years

• Perihelion distance = 1.5 AUPerihelion distance = 1.5 AU

• Radius = 2.6 ± 0.5 kmRadius = 2.6 ± 0.5 km

• Albedo = 0.07 ± 0.03Albedo = 0.07 ± 0.03

• Rotation Period ~ 24 or 41 hours Rotation Period ~ 24 or 41 hours

• Shape, 1.3 < Axial ratio < 3Shape, 1.3 < Axial ratio < 3

Ernst Wilhelm Leberecht Tempel(1821 - 1889)

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Sky PlotSky Plot

• Impact approx 06:00 - 06:30 UTC on 4 July 2005• RA, DEC = 13:38, -9.6• Geocentric Distance = 0.894 AU• Heliocentric Distance = 1.506 AU

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CO Lines Drive HRI IR CO Lines Drive HRI IR SensitivitySensitivity

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Sample DataSample Data

Barringer Meteor Crater seen with Barringer Meteor Crater seen with comparable number of pixels as Deep comparable number of pixels as Deep Impact crater assuming nominal model for Impact crater assuming nominal model for crateringcratering

MRI (full-frame)

HRI (full-frame)

E-2 hrs, 81369 km E-0 sec, 8606 km E+800 sec, 711 km