Mars Micro Orbiter (MMO)

• Mike Malin (MSSS) PI/Project Manager

• Bruce Cantor (MSSS) Project Scientist

• Melinda Kahre (ARC) Co-I

• Timothy McConnochie (JHU) Co-I

• Michael Smith (GSFC) Co-I

• Michael Wolff (SSI) Co-I

• T. Yee (MSSS) Dpty Proj Mgr; S/C Lead Eng.

• T. Svitek (Stellar Exploration) Sys Engineer

• Institutions and Responsibilities

• Malin Space Science Systems

• Project Management, Payload, Avionics, 

Software, Attitude Control System, 

Mechanical Design, Solar Panels

• Stellar Exploration

• System Engineering, Propulsion, 

Telecom, Power Management/storage

• Space Exploration Engineering

• Mission Design & Trajectory Analysis

• TZero, Inc.

• Launch Service Support Engineering

• Advanced Solutions, Inc.

• ACS/GNC & Flight Software Support

• Goddard Space Flight Center

• Technical advice, guidance, peer review
Mission Objectives

• Level 1 Requirements

• Get into Mars Orbit

• Acquire science data (visible and thermal IR imaging from Mars 

orbit

• Demonstrate Telecom Relay for Landed Assets

• Science Objectives

• Extend the temporal coverage of the global synoptic meteorological 

record (atmospheric thermal structure, dust and condensate clouds, and 

seasonal and perennial polar cap behavior).

• Characterize the dynamics and energy budget of the current Mars 

atmosphere.

• Key Observations

• Diurnal (Temporal) coverage,

• Obtain diurnal coverage not obtained since Viking IRTM.

• Obtain more spatial and diurnal coverage of planet each season than 

Viking.

• Polar (Spatial) coverage,

• Global Spatial coverage (to a slightly lesser extent than polar 

coverage)
Diurnal & Seasonal Coverage 

Optimized by 55° high altitude orbit

• Diurnal coverage is provided by orbit inclined by 55 deg.

• Diurnal coverage shifts about 2 hours per month. 

• Full temporal coverage takes about 5 months, but we obtain multiple 

days of coverage during that period, exceeds the minimum science 

requirement of 2 observations at each hour at each location on the planet 

per season.

• Good high latitude coverage.

Current (MARCI+MCS) MMO
Mission Design & Trajectory

• Launch on 2020 Atlas V on 17 July 2020

• Weekly tracking uses ∆DOR, 4-6 TCMs

• Arrives 19 Feb 2021, will be phased with 2020 entry

• Orbit

• 55° inclination, 4481 km altitude, with a period of 5.9 hr

(advances 15° each sol) relative to surface

• MOI ∆V ~1200 m/s (40 min burn) + 780 m/s circularization
Science Filters

Visible RGB

Camera IR Camera 1 IR Camera 2
Infrared Atmospheric CO2 [14 μm]

Altitude Weighted Bandpasses

To distinguish the vertical profile of dust and water ice condensate on the limb 

and to cover the entire diurnal cycle, we placed “hard requirements” (minimum 

requirement) for:

• Three-point thermal profile 

• Limb scale ≤ ~ 15 km

Orbits meet scale requirement. 

Other IR Camera Requirements

• Temperature Sampling: 140–305 K

• SNR = 0.02 W/m2/sr

• Two-point Calibration consisting:

1.) Onboard temperature target

2.) Empty space imaging

Improve SNR, use creative summing scheme (along areas of constant altitude) 

to preserve limb resolution. 
Example Mission Data Return

• Representative Mission data return

• Pink curve is spacecraft downlink range dependent downlink bit rate (kbps)

• Light Blue curve is hypothetical DSN downlink profile as function of bit rate (kbps)

• Yellow curve is hypothetical mission total data volume as function of tailored DSN pass 

allocation and bit rates

• Mission total bits = 87.34 Gb

6 passes in 6 sols

3 passes 

in 6 sols

2 passes 

in 6 sols

2 passes 

in 6 sols

3 passes 

in 6 sols
Spacecraft Subsystems

• Primarily a propulsion system with a small amount of telecom, 

avionics, power, and science

• ≥ 80% of volume ~16.4 kg mass is propellant (Hydrazine and 

Nitrogen Tetroxide (NTO-MON3); ISP ~ 285 sec

• Pump-pressurized, four 3 Nt thrusters, 120 psi

operating pressure

• Remaining ~2U includes ~

• 3 MSSS cameras (C-50 and IR3A)

• 8 position filter whe el (MSL-derived) with 

two calibration positions

• Xilinx Zinq 7045 1600 MIPS processor

• 2 TBytes of Mass Storage (5 x 400 GB 

μSD cards)

• 3 Software Defined Radios (SDRs)

• 1 power and 1 propulsion system 

management boards

• Antennas for Ka-band for downlink to 

Earth, S-band up/down for command-ing

and tracking, and UHF for relay

• 3 Reaction Wheels, 1 star camera, 2 sun 

sensors, 1 IMU (MEMS)

• 2 solar panels with 3 arrays/panel
Packaging

System is limited by volume capacity of Dispenser. 12U is actually 

~17.6 liters; S/C dry Mass including propulsion hardware and tanks is 

~13.4 kg, wet mass is ~30 kg. Launch mass including dispenser and

vibration isolation 

mounting is about 

36 kg. 2 would fit 

on Centaur Aft 

Bulkhead Carrier 

with small margin.
Aft Bulkhead Carrier 

(ABC)

12U Canisterized 

Satellite Dispenser (CSD)

Launch Accommodation
Propulsion System Options

For our desired mission, we needed a high ∆V (MOI), a relatively high Specific Impulse,

sufficient thrust to keep the MOI burn relatively short, all within a relatively small package

(12U). We concluded a biprop was our only way to meet these criteria. The system fills a

trade space of 1-10 kg payload mass, 6-27U volume & mass, and 1000 to 3000 m/s ∆V,

within the ABC constraints