AAS - 1 Jun 2004sam - 1 The Small Telescope Science Program Deep Impact Mission Stephanie McLaughlin (Univ. of Maryland) Lucy McFadden (Univ. of Maryland) Gary Emerson (Ball Aerospace & Technologies)

AAS - 1 Jun 2004sam - 2 An Overview of Deep Impact Fundamental scientific objective: probe beneath a cometary surfaceFundamental scientific objective: probe beneath a cometary surface Two-component spacecraft: Flyby spacecraft and auto-guided, imaging impactorTwo-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 craterImpact with comet 9P/Tempel 1 on July 4, 2005 will form ~100m crater

AAS - 1 Jun 2004sam - 3 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: –Discovered in 1867 but lost from 1869 to 1972 –Rather dim, 9th magnitude And, time on large telescopes is limited...And, time on large telescopes is limited...

AAS - 1 Jun 2004sam - 4 Small Telescopes to the Rescue Advanced amateurs and private observatories can provide good temporal coverage to supplement sparse baselinesAdvanced amateurs and private observatories can provide good temporal coverage to supplement sparse baselines Typically have:Typically have: –Fast, wide-field telescopes –High-quality, commercial CCD cameras –UBVRI filters Combination good for:Combination good for: –Imaging and photometry of dust coma (RI) –Imaging of jet activity and outbursts? (VRI) Hence, the STSP...Hence, the STSP...

AAS - 1 Jun 2004sam 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 Originator: Gary EmersonOriginator: 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 CCD images Program in hibernation for past 3 years, except for:Program in hibernation for past 3 years, except for: –DS/1, LINEAR C/2000 W1, Stardust Re-launches this fallRe-launches this fall Continues through 2005Continues through UT The George Observatory, Fort Bend Astro. Club

AAS - 1 Jun 2004sam - 6 STSP: Filling the Gaps Northern Obs: Oct ‘04 - Aug ‘05Northern Obs: Oct ‘04 - Aug ‘05 Southern Obs: Feb - Dec ‘05Southern Obs: Feb - Dec ‘05 STSP contributionsSTSP contributions Dust production light curve:Dust production light curve: Large telescope contributions Impact Impact: One day before perihelionImpact: One day before perihelion

AAS - 1 Jun 2004sam - 7 Jet Activity and Outbursts? Evidence for jet activity during 1983 apparitionEvidence for jet activity during 1983 apparition –Upper: 3 months pre-perihelion –Lower: 1 month pre-perihelion Expect jet activity 3-4 months before perihelion, Mar - Jun 2005Expect jet activity 3-4 months before perihelion, Mar - Jun 2005 Not sure if comet has outbursts; continuous imaging over the next year is neededNot sure if comet has outbursts; continuous imaging over the next year is needed Impact is expected to make a new active area: Jets or outbursts days or weeks after impact?Impact is expected to make a new active area: Jets or outbursts days or weeks after impact? STSP observers can help monitor for pre- and post-impact activitySTSP observers can help monitor for pre- and post-impact activity Jean-Claude Merlin (ICQ 1983)

AAS - 1 Jun 2004sam - 8 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 Dec 2005Aperture photometry (RI): Oct 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 after the Pro-Am Session!Interested? Please contact us after the Pro-Am Session! Stef McLaughlin Gary Emerson or visit the STSP website: 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.

AAS - 1 Jun 2004sam - 9 Backup Slides

AAS - 1 Jun 2004sam - 10 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

AAS - 1 Jun 2004sam - 11 Inter-Planetary Trajectory

AAS - 1 Jun 2004sam - 12 Encounter Schematic Tempel 1 Nucleus Shield Mode Attitude through Inner Coma Science and Autonav Imaging to Impact 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

AAS - 1 Jun 2004sam P/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 ± 0.03Albedo = 0.07 ± 0.03 Rotation Period ~ 24 or 41 hoursRotation Period ~ 24 or 41 hours Shape, 1.3 < Axial ratio < 3Shape, 1.3 < Axial ratio < 3 Ernst Wilhelm Leberecht Tempel ( )

AAS - 1 Jun 2004sam - 14 Sky Plot Impact approx 06: :30 UTC on 4 July 2005 RA, DEC = 13:38, -9.6 Geocentric Distance = AU Heliocentric Distance = AU

AAS - 1 Jun 2004sam - 15 CO Lines Drive HRI IR Sensitivity

AAS - 1 Jun 2004sam - 16 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, km E-0 sec, 8606 km E+800 sec, 711 km