1. Mars Environmental Observer A Scout Mission Concept Final report 25 February 2002 M. Janssen M. Allen

2. Concept History A tale of two instruments May 2001 MAMBO Atmospheric Sounding/ Chemistry On CNES Premier Orbiter January 2002 Follow-on MATMOS Mars Solar Occultation FTS MCS IR sounder MARCI Supporting camera MEO Proposed US participation to be proposed as Mission of Opportunity MEO Scout Concept Study MOMES Millimeter Spectrometer (US/DLR) MATMOS MARCI MEO Final MIRO Submillimeter spectrometer on Rosetta (US/DLR/French) ATMOS Solar occultation FTS on Space Shuttle Heritage MAMBO Millimeter Spectrometer (French/US/DLR) MOSES Submm Spectrometer (US/DLR) MATMOS Primary Instrument for MARVEL Scout To be proposed as a Scout Mission

3. Agenda MEO MAMBO MARVEL Janssen Allen 15 min

4. MEO Science Goals and Objectives 1. Seek evidence of extant life by a uniquely broad and sensitive mapping of the global distribution of atmospheric water (I.A.1). 2. Seek evidence of extant life by an ultra-high sensitivity search for trace atmospheric disequilibrium biosignatures (addresses objectives in I.A.2 by remote means). 3. Determine the oxidation state of the lower atmosphere and surface through highly sensitive global measurements of key trace photochemical oxidized species (II.A.6). 4. Characterize the present Mars climate by acquiring a complete global measurement of the physical state of the atmosphere— temperature and winds—over a wide altitude range and under all atmospheric conditions (II.A.1, IV.A.4). 5. Characterize present Mars climate processes through simultaneous measurements of temperature and water (II.A.1, II.A.3, II.A.4, II.A.5). 6. Determine the composition of surface dust by characterizing the mineralogy of atmospheric dust (addresses aspects of I.A.4, I.C.3, II.B.1, III.A.2, III.A.5). 7. Infer the presence of active volcanism through the detection of trace tectonic-formed gas emissions. (III.A.4) 8. Support the preparation for human exploration through a better understanding of upper atmospheric phenomena relevant to aerobraking and aerocapture (IV.A.4). LIFE CLIMATE GEOLOGY HUMAN EXPLORATION The Mars Environmental Observer (MEO) concept addresses the key Mars Exploration Program Goals of Life, Climate, Geology, and Human Exploration (MEPAG goals I-IV). MEO Objectives are:

5. Mission and Flight System Architecture Payload mass, power, and viewing requirements are accommodated by Lockheed-Martin Odyssey spacecraft. Launched by the Delta 2925 for the 2007 opportunity. The limb-sounding and solar occultation observing requirements are satisfied by the sun-synchronous polar orbit.

6. MEO Budget Mission costs with full (MATMOS, MOMES, MARCI) instrument complement

7. 200 MHz 330.6 GHz345.8 GHz325.2 GHz 12 CO 200 MHz 13 COH 2 16 O Advantages over IR: Insensitive to dust presence Doppler winds High H 2 O sensitivity Temperature and Water Vapor will be profiled using limb (shown) and nadir sounding in CO and H 2 O lines Winds will be profiled by limb sounding CO Atmospheric chemistry involving H 2 O 2, O 3, HDO, CO, will also be addressed Atmospheric Sounding with MAMBO Tangent altitude = 10 km Spectrometer width

8. Mars Zonal Wind Simulation for Northern Sosltice Figure from Conway Leovy (Nature Insight 412, 6843,245-249(2001))-derived from GCM of Haberle et al., J. Geophys. Res. 102, 13301-13311 (1993) Westward wind, m/secEastward wind, m/sec 80S 60 40 20 0 20 40 60 80N Latitude

9. Retrieval Error, m/s Altitude, km Wind Retrieval Winds along the line of sight will be measured from the Doppler shift of CO lines in the limb-sounding mode. 12 CO and 13 CO lines allow a wide altitude range to be covered in the atmosphere. The weighting function for the measurement is narrow in the limb sounding mode and the vertical resolution is set by the beamwidth on the limb (~10 km). Nominal receiver performance with 10-sec integration time/point allows the determination of wind velocity profiles to better than 10 m/s over a large altitude range. 12 CO 13 CO Lines with widths from 1 to 200 MHz are measured at 100 KHz resolution. cut for weighting function

10. MAMBO Collaboration Work Agreement Calibration Load1st LO Scan Mechanism 23-cm Off-Axis Antenna 335 GHz Receiver Power Processor HKPUSO Receiver Backend IF Processor Frequency Synthesizer Chirp Transform Spectrometer Power Processor CPU Electronics Interface S/C Data Bus S/C Power Bus Signal US French German MAMBO will be built as an international collaboration. A working agreement has been negotiated that minimizes interface complexity and plays to the respective strengths of the partners.

11. MAMBO US Component Science Team Mike Janssen (lead) Mark Allen Gordon Chin Todd Clancy Margaret Frerking Sam Gulkis Mark Gurwell Bob Haberle Mark Richardson Yuk Yung JPL GSFC U. Colo JPL Harvard ARC Caltech The US MAMBO science team comes from a variety of universities and NASA centers, and brings world-class expertise in all aspects of the investigation: instrumentation, remote sensing, atmospheric dynamics and chemistry

12. MAMBO US Component Rationale Continues international collaboration on heterodyne spectroscopy - this time with French lead US responsibility for subsystem complements limited French workforce & experience Choice of radiometer backend provides well-defined interface and minimizes risk, travel, ITAR issues, etc. Backend experience will be valuable for future instruments We have found no significant descope options that appear viable. Possibilities are being explored: –Swedish collaborators assume backend delivery responsibility, or –French contract to industry for this US role would be questionable in these cases

13. MAMBO US Component Budget 02040305060708091011 7654321076543210 Schedule of Deliverables STM EM FM Cost/FY, M$ FY Schedule Key Subsystem design and fab at JPL Delivery to LERMA (French) Support integration at LERMA Delivery to CNES (from draft AO) Budget Key and Summary Hardware $15.8 M Reserves $4.8 M Science $4.8 M Total $25.4M Note: 3%/yr inflation assumed (NASA model) launch Phase B