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Mars Atmosphere and Volatile EvolutioN (MAVEN) Overall Approach to Planetary Protection Wednesday, October 20, 2010. MAVEN Planetary Protection Lead Bob Bartlett. Status of MAVEN Planetary Protection Activity.
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Mars Atmosphere and Volatile EvolutioN (MAVEN) Overall Approach to Planetary Protection Wednesday, October 20, 2010 MAVEN Planetary Protection Lead Bob Bartlett
Status of MAVEN Planetary Protection Activity • With MPO and HQ approval, the MAVEN Planetary Protection Plan (PPP) was baselined and is under CCB control, MAVEN PM PLAN-0067. • Planning is underway for the Planetary Protection Implementation Document (PPID), due 60 days prior to CDR. This document will establish the MAVEN process for demonstrating our compliance with the requirements of NPR 8020.12C in accordance with the MAVEN PPP. • Two activities will support planning for the PPID • Lockheed Martin has reviewed the MRO Breakup and Burnup (B&B) analysis to gain insights to the MAVEN B&B analysis which will be available later in Phase C. • Today’s instrument focused planetary protection tutorial to assist instrument planetary protection implementation planning and Planetary Protection Equipment List (PPEL) development.
Breakup and Burnup Analysis • MRO was the first orbiter to use this methodology to satisfy PP requirements • Spacecraft trajectory is modeled for atmospheric entry • Aerodynamics are either tumbling or stable • Points are identified where components would separate from main spacecraft • Separate trajectories are initiated for each new object, all the way down to box-level • Aerothermal heating is tracked for each object • Thermal analysis determines temperature profile and whether item is sterilized during reentry • If the temperature reaches 500 oC or higher for at least 0.5 sec, it is considered sterilized (other criterion are under study for the PPO by JPL) • This is sufficient for externally contaminated items • Items with embedded organics may fail this criteria and carry their spore count forward to the final assessment • Total spore burden is based on items that do not vaporize or reach sterilization temperature • These items may be subject to cleaning if needed • The Planetary Protection Equipment List provides the bioburden accounting
MAVEN Planetary Protection Plan (PPP) Complies with NPR 8020.12C PPP Sections of particular interest for instrument developers: • Section 4.0, Planetary Protection Requirement Pg. 15 • Section 6.0, Approach to Compliance Pg. 27 • Section 7.0, Supporting Analysis (mainly B&B) Pg. 33 • Section 8.0, Planetary Protection Reviews Pg. 39 • Typically associated with principal project reviews • Section 9.0. Planetary Protection Documentation Pg. 39 • 9.1, Planetary Protection Implementation Document • 9.2, Pre-Launch Report • 9.3, Post-Launch Report • 9.4, Extended Mission Report • 9.5, End-of-Mission Report • 9.6, Documentation Schedule
Flow Diagram of the Bioburden Analysis and Reduction Process < 5 x 105 Breakup & Burnup Analysis Generate Planetary Protection Equipment List Estimate Bioburden using 8020.12C Y Accountable Spores • Entry velocity & angle • Structure degradation stable & tumbling • Thermal analysis > 500 C for > 0.5 sec • Ablation N Launch Revise Bioburden Estimate With DHMR or Other Mitigations Some Programmatic Issues (cost & schedule) • Modifying component flow through ATLO from a PP perspective • Perform spore remediation as necessary Perform Breakup & Burnup Analysis < 5 x105 Update Bioburden Estimate Further ATLO Remediation & Assay Sterilized Element List Bioburden Mitigation N Accountable Spores Y Launch
High Level Working Schedule for Planetary Protection Implementation Orbiter Breakup Module Burnup Module Spore Assessment MAVEN Assessment Assays Spore Mitigation PDR CDR LAUNCH Reporting & Reviews Jan-10 Jul-10 Jan-11 Jul-11 Jan-12 Jul-12 Dec-12 Jul-13 Dec-13 Jul-14
General Planetary Protection Guidelines for Instrument Development • Clean all subassemblies prior to system assembly using instrument developer’s practice and procedures (CCP) • This starts at the lowest level of assembly which is inspectable, such as a completed PWB or mechanical piece part. • Assemble & Test in Class 10K or better (or suitably bagged), documenting any exceptions with a record of exposure times to worse environments. • Bio Assay of a representative PWB just prior to installation; the assay results should be provided to the project as soon as practicable, typically 500 spores/m2 or less. • Ship in a sealed, clean package; on acceptance a bio assay will be taken of an external instrument surface to confirm no bio contamination occurred in transit
Plan Forward • Lockheed Martin will undertake the MAVEN Breakup and Burnup (B&B) analysis following KDP C with the objective of identifying elements of MAVEN which may impact Mars without sufficient heating to be sterilized. • Lockheed Martin will undertake development of the Flight Segment Planetary Protection Implementation Plan. • Following PDR the MAVEN Planetary Protection Working Group (PPWG) has been looking in more detail at the issues related to instruments including bioburden, methods for bioburden reduction, and assays at the instrument sites. • In Phase C the PPWG will undertake the development of the Planetary Protection Implementation Document, due 60 days prior to CDR. This document will establish the MAVEN process for demonstrating we meet the requirements of NPR 8020.12C