Multimission Automated Deepspace Conjunction Assessment Process (MADCAP)

The Multimission Automated Deepspace Conjunction Assessment Process (MADCAP) at NASA Jet Propulsion Laboratory (JPL) is responsible for screening ephemerides for NASA spacecraft not orbiting the Earth against ephemerides for other spacecraft orbiting the same central body/point.  Since there is no catalog of objects at other bodies because non-cooperative tracking is not currently available in those flight regimes, screening of predicted ephemerides against each other is the only way for satellite owner/operators to predict and mitigate close approaches.  NASA gladly accepts shared ephemerides from non-NASA operators who also have spacecraft at these bodies in the interest of flight safety. MADCAP is a service provided by NASA’s Advanced Multimission Operations System (AMMOS).

Conjunction Assessment Process For Mars Orbiters Rev3 (PDF)
Conjunction Assessment Process For Lunar Orbiters (PDF)

MADCAP Conjunction Events

MADCAP publications

Automated Spacecraft Conjunction Assessment at Mars and the Moon
Berry, D. S., Guinn, J. R., Tarzi, Z. B., & Demcak, S. W., “Automated Spacecraft Conjunction at Mars and the Moon”, Paper 1262983, 12th International Conference on Space Operations, Stockholm, Sweden, June 2012. Initial description of the Multimission Automated Deepspace Conjunction Assessment Process (MADCAP), originally used at Mars and the Moon but applicable to other shared orbital environments.

Automated Spacecraft Conjunction Assessment at Mars and the Moon

An Updated Process for Automated Deepspace Conjunction Assessment
Tarzi, Z., Berry, D., Roncoli, R., “An Updated Process for Automated Deepspace Conjunction Assessment”, Paper AAS 14-373, 25th International Symposium on Space Flight Dynamics, Munich, Germany, October 2015. General update of MADCAP processing including improved classification of close approaches, more advanced automation, more informative reports. Special focus on close approaches of NASA’s LADEE and LRO during the LADEE mission, and process changes influenced by the MAVEN mission.

An Updated Process for Automated Deepspace Conjunction Assessment

Automated Spacecraft Conjunction Assessment at Mars and the Moon-A Five Year Update
Berry, D., Tarzi, Z., Roncoli, R., Wilson, R., “Automated Spacecraft Conjunction Assessment at Mars and the Moon-A Five Year Update”, Paper 2810036, 14th International Conference on Space Operations, Marseille, France, May 2018. Provides a five year update on MADCAP operations at Mars and the Moon focusing on implementation of a number of features identified in the initial paper as “future work”. Also discussed are process changes in a few unplanned but important areas.

MADCAP Spaceops 2018 paper.pdf

Deriving Event Thresholds And Collision Probability for Automated Conjunction Assessment at Mars and The Moon
Tarzi, Zahi B., Young, Brian T., Berry, David S., “Deriving Event Thresholds and Collision Probability for Automated Conjunction Assessment at Mars and the Moon”, AAS 22-042, 2022 AAS/AIAA Astrodynamics Specialist Conference, Charlotte, NC, August, 2022. Detailed explanation of the development of thresholds used in MADCAP to determine whether or not spacecraft close approaches require active mitigation. Provides guidelines and methods for navigation teams to derive these thresholds from their orbit determination analysis. 

AAS_22-042_paper