1. AstroCon2004 - Jul 23sam - 1 The Small Telescope Science Program Deep Impact Mission Stephanie McLaughlin (Univ. of Maryland) Lucy McFadden (Univ. of Maryland) Gary Emerson (Ball Aerospace & Technologies)

2. AstroCon2004 - Jul 23sam - 2 An Overview of Deep Impact Fundamental scientific objective:Fundamental scientific objective: Probe beneath a cometary surface Two-component spacecraft:Two-component spacecraft: Flyby spacecraft and auto-guided, imaging impactor Launch in December 2004Launch in December 2004 Impact with comet 9P/Tempel 1 on July 4, 2005 will form ~100m-wide craterImpact with comet 9P/Tempel 1 on July 4, 2005 will form ~100m-wide crater

3. AstroCon2004 - Jul 23sam - 3 9P/Tempel 1 History:History: –April 1867 discovered –1873, 1879 observed –1881 close approach to Jupiter, then lost –1967 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 ± 0.03 (dark!)Albedo = 0.07 ± 0.03 (dark!) Rotation Period = ~38 hoursRotation Period = ~38 hours Shape, 1.3 < Axial ratio < 3Shape, 1.3 < Axial ratio < 3 Maximum visual magnitude = ~9.3Maximum visual magnitude = ~9.3 Ernst Wilhelm Leberecht Tempel (1821 - 1889)

4. AstroCon2004 - Jul 23sam - 4 Ground-based Observations Science team is conducting a vigorous program of ground-based observations:Science team is conducting a vigorous program of ground-based observations: –Volatile outgassing –Dust coma development –Jet activity and outbursts Goal: Establish baselines of Tempel 1’s activity for comparison to impact and post- impact observationsGoal: Establish baselines of Tempel 1’s activity for comparison to impact and post- impact observations However, few observations of Tempel 1:However, few observations of Tempel 1: –Lost for nearly 100 years –Rather dim, 9th magnitude –Time on large telescopes is limited...

5. AstroCon2004 - Jul 23sam - 5 Small Telescopes to the Rescue Advanced amateurs and private observatories can provide good temporal coverage to supplement baselinesAdvanced amateurs and private observatories can provide good temporal coverage to supplement baselines Advanced observers typically have:Advanced observers typically have: –Fast, wide-field telescopes –High-quality, commercial CCD cameras –UBVRI filters Combination is good for:Combination is good for: –Imaging and aperture photometry of dust coma (RI) Wide format captures field stars in same frame as comet, simplifying calibrationsWide format captures field stars in same frame as comet, simplifying calibrations –Imaging and monitoring of jet activity and outbursts (VRI) Hence, the STSP...Hence, the STSP...

6. AstroCon2004 - Jul 23sam - 6 2000-08-26.1 UT, 1x180s, R Filter Wendelstein Observatory, M. Tschimmel The Small Telescope Science Program The STSP is an E/PO project for the missionThe STSP is an E/PO project for the mission Brainchild of Gary EmersonBrainchild of Gary Emerson Campaign in 2000, very successful:Campaign in 2000, very successful: –Network of 40+ observers in 12 countries, spanning 6 continents –Observers acquired 700+ VRI and 300+ unfiltered, raw CCD images Program in hibernation for past 3 years, except for:Program in hibernation for past 3 years, except for: –Borrelly, Wild 2, LINEAR C/2000 W1 Re-launches this fallRe-launches this fall Continues through 2005Continues through 2005 2000-08-06.3 UT The George Observatory, Fort Bend Astro. Club

7. AstroCon2004 - Jul 23sam - 7 STSP: Filling the Gaps Northern Obs: Oct 2004 - Aug 2005Northern Obs: Oct 2004 - Aug 2005 Southern Obs: Feb - Dec 2005Southern Obs: Feb - Dec 2005 STSP contributionsSTSP contributions Dust production light curve:Dust production light curve: Large telescope contributions Impact:Impact: 06:08 July 4 2005 UT Perihelion:Perihelion: 08:40 July 5 2005 UT Impact & Perihelion

8. AstroCon2004 - Jul 23sam - 8 Jet Activity and Outbursts? Evidence for jet activity: 1983 apparitionEvidence for jet activity: 1983 apparition –Upper: 3 months pre-perihelion –Lower: 1 month pre-perihelion Expect jet activity 3-4 months before perihelion: Mar - Jul 2005Expect jet activity 3-4 months before perihelion: Mar - Jul 2005 Outbursts? Need continuous imagingOutbursts? Need continuous imaging Expect new active area after impact  Jets or outbursts days or weeks after impact?Expect new active area after impact  Jets or outbursts days or weeks after impact? STSP observers: Monitor for pre- and post- impact activitySTSP observers: Monitor for pre- and post- impact activity Jean-Claude Merlin (ICQ 1983)

9. AstroCon2004 - Jul 23sam - 9 What We’re Looking for... Advanced amateur observers with discretionary telescope timeAdvanced 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? Please contact us!Interested? Please contact us! Stef McLaughlin (stefmcl@astro.umd.edu) Gary Emerson (emerson@ball.com) Or visit the STSP website: http://deepimpact.astro.umd.edu/stsp http://deepimpact.astro.umd.edu/stsphttp://deepimpact.astro.umd.edu/stsp 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, Kluwer Academic Publishers, 2003, p. 57.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, Kluwer Academic Publishers, 2003, p. 57.

10. AstroCon2004 - Jul 23sam - 10 Backup Slides

11. AstroCon2004 - Jul 23sam - 11 Scientific Objectives Primary Scientific ThemePrimary Scientific Theme –Understand the differences between interior and surface –Determine basic cometary properties (density, porosity, etc.) –Search for pristine material below surface Secondary Scientific ThemeSecondary Scientific Theme –Distinguish extinction from dormancy Additional Science AddressedAdditional Science Addressed –Address terrestrial hazard from cometary impacts –Search for heterogeneity at scale of cometesimals –Calibrate the cratering record

12. AstroCon2004 - Jul 23sam - 12 Inter-Planetary Trajectory

13. AstroCon2004 - Jul 23sam - 13 Encounter Schematic Tempel 1 Nucleus Shield Mode Attitude through Inner Coma Science and Autonav Imaging to Impact + 800 sec ITM-1 E-88 min ITM-2 E-48 min ITM-3 E-15 min Impactor Release E-24 hours AutoNav Enabled E-2 hr Flyby S/C Deflection Maneuver E-23.5 hr 2-way S-band Crosslink 500 km

14. AstroCon2004 - Jul 23sam - 14 Sky 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

15. AstroCon2004 - Jul 23sam - 15 Earth-Based Elevation

16. AstroCon2004 - Jul 23sam - 16 CO Lines Drive HRI IR Sensitivity

17. AstroCon2004 - Jul 23sam - 17 Sample Data Barringer Meteor Crater seen with comparable number of pixels as Deep Impact crater assuming nominal model for cratering MRI (full-frame) HRI (full-frame) E-2 hrs, 81369 km E-0 sec, 8606 km E+800 sec, 711 km